Merge with MySQL 5.1.57/58

Moved some BSD string functions from Unireg

83 files changed, 2168 insertions, 572 deletions

diff --git a/storage/heap/ha_heap.cc b/storage/heap/ha_heap.cc
index fb7c13e4e41..9f29dee2030 100644
--- a/storage/heap/ha_heap.cc
+++ b/storage/heap/ha_heap.cc
@@ -142,11 +142,11 @@ int ha_heap::close(void)
   DESCRIPTION
     Do same as default implementation but use file->s->name instead of 
     table->s->path. This is needed by Windows where the clone() call sees
-    '/'-delimited path in table->s->path, while ha_peap::open() was called 
+    '/'-delimited path in table->s->path, while ha_heap::open() was called 
     with '\'-delimited path.
 */
 
-handler *ha_heap::clone(MEM_ROOT *mem_root)
+handler *ha_heap::clone(const char *name, MEM_ROOT *mem_root)
 {
   handler *new_handler= get_new_handler(table->s, mem_root, table->s->db_type());
   if (new_handler && !new_handler->ha_open(table, file->s->name, table->db_stat,
diff --git a/storage/heap/ha_heap.h b/storage/heap/ha_heap.h
index 22722129f4c..69751101645 100644
--- a/storage/heap/ha_heap.h
+++ b/storage/heap/ha_heap.h
@@ -34,7 +34,7 @@ class ha_heap: public handler
 public:
   ha_heap(handlerton *hton, TABLE_SHARE *table);
   ~ha_heap() {}
-  handler *clone(MEM_ROOT *mem_root);
+  handler *clone(const char *name, MEM_ROOT *mem_root);
   const char *table_type() const
   {
     return (table->in_use->variables.sql_mode & MODE_MYSQL323) ?
diff --git a/storage/innobase/btr/btr0cur.c b/storage/innobase/btr/btr0cur.c
index a7160d74a32..6c0497cbd41 100644
--- a/storage/innobase/btr/btr0cur.c
+++ b/storage/innobase/btr/btr0cur.c
@@ -66,6 +66,13 @@ this many index pages */
 /*--------------------------------------*/
 #define BTR_BLOB_HDR_SIZE		8
 
+/* Estimated table level stats from sampled value. */
+#define	BTR_TABLE_STATS_FROM_SAMPLE(value, index, ext_size, not_empty)	\
+	((value * (ib_longlong) index->stat_n_leaf_pages		\
+	  + BTR_KEY_VAL_ESTIMATE_N_PAGES - 1 + ext_size			\
+	  + not_empty)							\
+	 / (BTR_KEY_VAL_ESTIMATE_N_PAGES + ext_size))
+
 /***********************************************************************
 Marks all extern fields in a record as owned by the record. This function
 should be called if the delete mark of a record is removed: a not delete
@@ -2835,9 +2842,54 @@ btr_estimate_n_rows_in_range(
 }
 
 /***********************************************************************
+Record the number of non_null key values in a given index for
+each n-column prefix of the index where n < dict_index_get_n_unique(index).
+The estimates are eventually stored in the array:
+index->stat_n_non_null_key_vals. */
+static
+void
+btr_record_not_null_field_in_rec(
+/*=============================*/
+	rec_t*		rec,		/* in: physical record */
+	ulint		n_unique,	/* in: dict_index_get_n_unique(index),
+					number of columns uniquely determine
+					an index entry */
+	const ulint*	offsets,	/* in: rec_get_offsets(rec, index),
+					its size could be for all fields or
+					that of "n_unique" */
+	ib_longlong*	n_not_null)	/* in/out: array to record number of
+					not null rows for n-column prefix */
+{
+	ulint	i;
+
+	ut_ad(rec_offs_n_fields(offsets) >= n_unique);
+
+	if (n_not_null == NULL) {
+		return;
+	}
+
+	for (i = 0; i < n_unique; i++) {
+		ulint	rec_len;
+		byte*	field;
+
+		field = rec_get_nth_field(rec, offsets, i, &rec_len);
+
+		if (rec_len != UNIV_SQL_NULL) {
+			n_not_null[i]++;
+		} else {
+			/* Break if we hit the first NULL value */
+			break;
+		}
+	}
+}
+
+/***********************************************************************
 Estimates the number of different key values in a given index, for
 each n-column prefix of the index where n <= dict_index_get_n_unique(index).
-The estimates are stored in the array index->stat_n_diff_key_vals. */
+The estimates are stored in the array index->stat_n_diff_key_vals.
+If innodb_stats_method is "nulls_ignored", we also record the number of
+non-null values for each prefix and store the estimates in
+array index->stat_n_non_null_key_vals. */
 
 void
 btr_estimate_number_of_different_key_vals(
@@ -2851,6 +2903,8 @@ btr_estimate_number_of_different_key_vals(
 	ulint		matched_fields;
 	ulint		matched_bytes;
 	ib_longlong*	n_diff;
+	ib_longlong*	n_not_null;
+	ibool		stats_null_not_equal;
 	ulint		not_empty_flag	= 0;
 	ulint		total_external_size = 0;
 	ulint		i;
@@ -2858,24 +2912,47 @@ btr_estimate_number_of_different_key_vals(
 	ulint		add_on;
 	mtr_t		mtr;
 	mem_heap_t*	heap		= NULL;
-	ulint		offsets_rec_[REC_OFFS_NORMAL_SIZE];
-	ulint		offsets_next_rec_[REC_OFFS_NORMAL_SIZE];
-	ulint*		offsets_rec	= offsets_rec_;
-	ulint*		offsets_next_rec= offsets_next_rec_;
-	*offsets_rec_ = (sizeof offsets_rec_) / sizeof *offsets_rec_;
-	*offsets_next_rec_
-		= (sizeof offsets_next_rec_) / sizeof *offsets_next_rec_;
+	ulint*		offsets_rec	= NULL;
+	ulint*		offsets_next_rec = NULL;
 
 	n_cols = dict_index_get_n_unique(index);
 
-	n_diff = mem_alloc((n_cols + 1) * sizeof(ib_longlong));
+	heap = mem_heap_create((sizeof *n_diff + sizeof *n_not_null)
+			       * (n_cols + 1)
+			       + dict_index_get_n_fields(index)
+			       * (sizeof *offsets_rec
+				  + sizeof *offsets_next_rec));
+
+	n_diff = mem_heap_zalloc(heap, (n_cols + 1) * sizeof(ib_longlong));
+
+	n_not_null = NULL;
+
+	/* Check srv_innodb_stats_method setting, and decide whether we
+	need to record non-null value and also decide if NULL is
+	considered equal (by setting stats_null_not_equal value) */
+	switch (srv_innodb_stats_method) {
+	case SRV_STATS_NULLS_IGNORED:
+		n_not_null = mem_heap_zalloc(heap, (n_cols + 1)
+					     * sizeof *n_not_null);
+		/* fall through */
+
+	case SRV_STATS_NULLS_UNEQUAL:
+		/* for both SRV_STATS_NULLS_IGNORED and SRV_STATS_NULLS_UNEQUAL
+		case, we will treat NULLs as unequal value */
+		stats_null_not_equal = TRUE;
+		break;
 
-	memset(n_diff, 0, (n_cols + 1) * sizeof(ib_longlong));
+	case SRV_STATS_NULLS_EQUAL:
+		stats_null_not_equal = FALSE;
+		break;
+
+	default:
+		ut_error;
+	}
 
 	/* We sample some pages in the index to get an estimate */
 
 	for (i = 0; i < BTR_KEY_VAL_ESTIMATE_N_PAGES; i++) {
-		rec_t*	supremum;
 		mtr_start(&mtr);
 
 		btr_cur_open_at_rnd_pos(index, BTR_SEARCH_LEAF, &cursor, &mtr);
@@ -2888,18 +2965,25 @@ btr_estimate_number_of_different_key_vals(
 
 		page = btr_cur_get_page(&cursor);
 
-		supremum = page_get_supremum_rec(page);
 		rec = page_rec_get_next(page_get_infimum_rec(page));
 
-		if (rec != supremum) {
+		if (!page_rec_is_supremum(rec)) {
 			not_empty_flag = 1;
 			offsets_rec = rec_get_offsets(rec, index, offsets_rec,
 						      ULINT_UNDEFINED, &heap);
+
+			if (n_not_null) {
+				btr_record_not_null_field_in_rec(
+					rec, n_cols, offsets_rec, n_not_null);
+			}
 		}
 
-		while (rec != supremum) {
+		while (!page_rec_is_supremum(rec)) {
 			rec_t*	next_rec = page_rec_get_next(rec);
-			if (next_rec == supremum) {
+			if (page_rec_is_supremum(next_rec)) {
+				total_external_size +=
+					btr_rec_get_externally_stored_len(
+						rec, offsets_rec);
 				break;
 			}
 
@@ -2907,11 +2991,13 @@ btr_estimate_number_of_different_key_vals(
 			matched_bytes = 0;
 			offsets_next_rec = rec_get_offsets(next_rec, index,
 							   offsets_next_rec,
-							   n_cols, &heap);
+							   ULINT_UNDEFINED,
+							   &heap);
 
 			cmp_rec_rec_with_match(rec, next_rec,
 					       offsets_rec, offsets_next_rec,
-					       index, &matched_fields,
+					       index, stats_null_not_equal,
+					       &matched_fields,
 					       &matched_bytes);
 
 			for (j = matched_fields + 1; j <= n_cols; j++) {
@@ -2921,6 +3007,12 @@ btr_estimate_number_of_different_key_vals(
 				n_diff[j]++;
 			}
 
+			if (n_not_null) {
+				btr_record_not_null_field_in_rec(
+					next_rec, n_cols, offsets_next_rec,
+					n_not_null);
+			}
+
 			total_external_size
 				+= btr_rec_get_externally_stored_len(
 					rec, offsets_rec);
@@ -2955,10 +3047,6 @@ btr_estimate_number_of_different_key_vals(
 			}
 		}
 
-		offsets_rec = rec_get_offsets(rec, index, offsets_rec,
-					      ULINT_UNDEFINED, &heap);
-		total_external_size += btr_rec_get_externally_stored_len(
-			rec, offsets_rec);
 		mtr_commit(&mtr);
 	}
 
@@ -2971,14 +3059,8 @@ btr_estimate_number_of_different_key_vals(
 	included in index->stat_n_leaf_pages) */
 
 	for (j = 0; j <= n_cols; j++) {
-		index->stat_n_diff_key_vals[j]
-			= ((n_diff[j]
-			    * (ib_longlong)index->stat_n_leaf_pages
-			    + BTR_KEY_VAL_ESTIMATE_N_PAGES - 1
-			    + total_external_size
-			    + not_empty_flag)
-			   / (BTR_KEY_VAL_ESTIMATE_N_PAGES
-			      + total_external_size));
+		index->stat_n_diff_key_vals[j] = BTR_TABLE_STATS_FROM_SAMPLE(
+			n_diff[j], index, total_external_size, not_empty_flag);
 
 		/* If the tree is small, smaller than
 		10 * BTR_KEY_VAL_ESTIMATE_N_PAGES + total_external_size, then
@@ -2997,12 +3079,20 @@ btr_estimate_number_of_different_key_vals(
 		}
 
 		index->stat_n_diff_key_vals[j] += add_on;
-	}
 
-	mem_free(n_diff);
-	if (UNIV_LIKELY_NULL(heap)) {
-		mem_heap_free(heap);
+		/* Update the stat_n_non_null_key_vals[] with our
+		sampled result. stat_n_non_null_key_vals[] is created
+		and initialized to zero in dict_index_add_to_cache(),
+		along with stat_n_diff_key_vals[] array */
+		if (n_not_null != NULL && (j < n_cols)) {
+			index->stat_n_non_null_key_vals[j] =
+				 BTR_TABLE_STATS_FROM_SAMPLE(
+					n_not_null[j], index,
+					total_external_size, not_empty_flag);
+		}
 	}
+
+	mem_heap_free(heap);
 }
 
 /*================== EXTERNAL STORAGE OF BIG FIELDS ===================*/
diff --git a/storage/innobase/dict/dict0dict.c b/storage/innobase/dict/dict0dict.c
index fda6555e082..beea0a2f411 100644
--- a/storage/innobase/dict/dict0dict.c
+++ b/storage/innobase/dict/dict0dict.c
@@ -1358,6 +1358,12 @@ dict_index_add_to_cache(
 			new_index->heap,
 			(1 + dict_index_get_n_unique(new_index))
 			* sizeof(ib_longlong));
+
+		new_index->stat_n_non_null_key_vals = mem_heap_zalloc(
+			new_index->heap,
+			(1 + dict_index_get_n_unique(new_index))
+			* sizeof(*new_index->stat_n_non_null_key_vals));
+
 		/* Give some sensible values to stat_n_... in case we do
 		not calculate statistics quickly enough */
 
@@ -3817,6 +3823,10 @@ dict_update_statistics_low(
 			for (i = dict_index_get_n_unique(index); i; ) {
 				index->stat_n_diff_key_vals[i--] = 1;
 			}
+
+			memset(index->stat_n_non_null_key_vals, 0,
+			       (1 + dict_index_get_n_unique(index))
+                               * sizeof(*index->stat_n_non_null_key_vals));
 		}
 
 		index = dict_table_get_next_index(index);
diff --git a/storage/innobase/handler/ha_innodb.cc b/storage/innobase/handler/ha_innodb.cc
index 4c52326a58a..6f58fd70fbd 100644
--- a/storage/innobase/handler/ha_innodb.cc
+++ b/storage/innobase/handler/ha_innodb.cc
@@ -130,6 +130,25 @@ static my_bool	innobase_adaptive_hash_index	= TRUE;
 
 static char*	internal_innobase_data_file_path	= NULL;
 
+/* Possible values for system variable "innodb_stats_method". The values
+are defined the same as its corresponding MyISAM system variable
+"myisam_stats_method"(see "myisam_stats_method_names"), for better usability */
+static const char* innodb_stats_method_names[] = {
+	"nulls_equal",
+	"nulls_unequal",
+	"nulls_ignored",
+	NullS
+};
+
+/* Used to define an enumerate type of the system variable innodb_stats_method.
+This is the same as "myisam_stats_method_typelib" */
+static TYPELIB innodb_stats_method_typelib = {
+	array_elements(innodb_stats_method_names) - 1,
+	"innodb_stats_method_typelib",
+	innodb_stats_method_names,
+	NULL
+};
+
 /* The following counter is used to convey information to InnoDB
 about server activity: in selects it is not sensible to call
 srv_active_wake_master_thread after each fetch or search, we only do
@@ -6363,6 +6382,65 @@ ha_innobase::read_time(
 }
 
 /*************************************************************************
+Calculate Record Per Key value. Need to exclude the NULL value if
+innodb_stats_method is set to "nulls_ignored" */
+static
+ha_rows
+innodb_rec_per_key(
+/*===============*/
+					/* out: estimated record per key
+					value */
+	dict_index_t*	index,		/* in: dict_index_t structure */
+	ulint		i,		/* in: the column we are
+					calculating rec per key */
+	ha_rows		records)	/* in: estimated total records */
+{
+	ha_rows		rec_per_key;
+
+	ut_ad(i < dict_index_get_n_unique(index));
+
+	/* Note the stat_n_diff_key_vals[] stores the diff value with
+	n-prefix indexing, so it is always stat_n_diff_key_vals[i + 1] */
+	if (index->stat_n_diff_key_vals[i + 1] == 0) {
+
+		rec_per_key = records;
+	} else if (srv_innodb_stats_method == SRV_STATS_NULLS_IGNORED) {
+		ib_longlong	num_null;
+
+		/* Number of rows with NULL value in this
+		field */
+		num_null = records - index->stat_n_non_null_key_vals[i];
+
+		/* In theory, index->stat_n_non_null_key_vals[i]
+		should always be less than the number of records.
+		Since this is statistics value, the value could
+		have slight discrepancy. But we will make sure
+		the number of null values is not a negative number. */
+		num_null = (num_null < 0) ? 0 : num_null;
+
+		/* If the number of NULL values is the same as or
+		large than that of the distinct values, we could
+		consider that the table consists mostly of NULL value.
+		Set rec_per_key to 1. */
+		if (index->stat_n_diff_key_vals[i + 1] <= num_null) {
+			rec_per_key = 1;
+		} else {
+			/* Need to exclude rows with NULL values from
+			rec_per_key calculation */
+			rec_per_key = (ha_rows)(
+				(records - num_null)
+				/ (index->stat_n_diff_key_vals[i + 1]
+				   - num_null));
+		}
+	} else {
+		rec_per_key = (ha_rows)
+			 (records / index->stat_n_diff_key_vals[i + 1]);
+	}
+
+	return(rec_per_key);
+}
+
+/*************************************************************************
 Returns statistics information of the table to the MySQL interpreter,
 in various fields of the handle object. */
 
@@ -6568,13 +6646,8 @@ ha_innobase::info_low(
 					break;
 				}
 
-				if (index->stat_n_diff_key_vals[j + 1] == 0) {
-
-					rec_per_key = stats.records;
-				} else {
-					rec_per_key = (ha_rows)(stats.records /
-					 index->stat_n_diff_key_vals[j + 1]);
-				}
+				rec_per_key = innodb_rec_per_key(
+					index, j, stats.records);
 
 				/* Since MySQL seems to favor table scans
 				too much over index searches, we pretend
@@ -8990,6 +9063,13 @@ static MYSQL_SYSVAR_LONG(autoinc_lock_mode, innobase_autoinc_lock_mode,
   AUTOINC_OLD_STYLE_LOCKING,	/* Minimum value */
   AUTOINC_NO_LOCKING, 0);	/* Maximum value */
 
+static MYSQL_SYSVAR_ENUM(stats_method, srv_innodb_stats_method,
+   PLUGIN_VAR_RQCMDARG,
+  "Specifies how InnoDB index statistics collection code should "
+  "treat NULLs. Possible values are NULLS_EQUAL (default), "
+  "NULLS_UNEQUAL and NULLS_IGNORED",
+   NULL, NULL, SRV_STATS_NULLS_EQUAL, &innodb_stats_method_typelib);
+
 #if defined UNIV_DEBUG || defined UNIV_IBUF_DEBUG
 static MYSQL_SYSVAR_UINT(change_buffering_debug, ibuf_debug,
   PLUGIN_VAR_RQCMDARG,
@@ -9031,6 +9111,7 @@ static struct st_mysql_sys_var* innobase_system_variables[]= {
   MYSQL_SYSVAR(stats_on_metadata),
   MYSQL_SYSVAR(use_legacy_cardinality_algorithm),
   MYSQL_SYSVAR(adaptive_hash_index),
+  MYSQL_SYSVAR(stats_method),
   MYSQL_SYSVAR(status_file),
   MYSQL_SYSVAR(support_xa),
   MYSQL_SYSVAR(sync_spin_loops),
diff --git a/storage/innobase/include/btr0cur.h b/storage/innobase/include/btr0cur.h
index 213dcb7f568..20235c55f22 100644
--- a/storage/innobase/include/btr0cur.h
+++ b/storage/innobase/include/btr0cur.h
@@ -404,7 +404,10 @@ btr_estimate_n_rows_in_range(
 /***********************************************************************
 Estimates the number of different key values in a given index, for
 each n-column prefix of the index where n <= dict_index_get_n_unique(index).
-The estimates are stored in the array index->stat_n_diff_key_vals. */
+The estimates are stored in the array index->stat_n_diff_key_vals.
+If innodb_stats_method is nulls_ignored, we also record the number of
+non-null values for each prefix and stored the estimates in
+array index->stat_n_non_null_key_vals. */
 
 void
 btr_estimate_number_of_different_key_vals(
diff --git a/storage/innobase/include/dict0mem.h b/storage/innobase/include/dict0mem.h
index 2f2a7441478..83dbf65ea41 100644
--- a/storage/innobase/include/dict0mem.h
+++ b/storage/innobase/include/dict0mem.h
@@ -222,6 +222,12 @@ struct dict_index_struct{
 				for this index, for each n-column prefix
 				where n <= dict_get_n_unique(index); we
 				periodically calculate new estimates */
+	ib_longlong*	stat_n_non_null_key_vals;
+				/* approximate number of non-null key values
+				for this index, for each column where
+				n < dict_get_n_unique(index); This
+				is used when innodb_stats_method is
+				"nulls_ignored". */
 	ulint		stat_index_size;
 				/* approximate index size in database pages */
 	ulint		stat_n_leaf_pages;
diff --git a/storage/innobase/include/dict0types.h b/storage/innobase/include/dict0types.h
index b90545f2105..6674b5ff397 100644
--- a/storage/innobase/include/dict0types.h
+++ b/storage/innobase/include/dict0types.h
@@ -16,11 +16,6 @@ typedef struct dict_index_struct	dict_index_t;
 typedef struct dict_table_struct	dict_table_t;
 typedef struct dict_foreign_struct	dict_foreign_t;
 
-/* A cluster object is a table object with the type field set to
-DICT_CLUSTERED */
-
-typedef dict_table_t			dict_cluster_t;
-
 typedef struct ind_node_struct		ind_node_t;
 typedef struct tab_node_struct		tab_node_t;
 
diff --git a/storage/innobase/include/rem0cmp.h b/storage/innobase/include/rem0cmp.h
index c6a6e5de4db..22a22d13e17 100644
--- a/storage/innobase/include/rem0cmp.h
+++ b/storage/innobase/include/rem0cmp.h
@@ -141,6 +141,10 @@ cmp_rec_rec_with_match(
 	const ulint*	offsets1,/* in: rec_get_offsets(rec1, index) */
 	const ulint*	offsets2,/* in: rec_get_offsets(rec2, index) */
 	dict_index_t*	index,	/* in: data dictionary index */
+	ibool		nulls_unequal,
+				/* in: TRUE if this is for index statistics
+				cardinality estimation, and innodb_stats_method
+				is "nulls_unequal" or "nulls_ignored" */
 	ulint*		matched_fields, /* in/out: number of already completely
 				matched fields; when the function returns,
 				contains the value the for current
diff --git a/storage/innobase/include/rem0cmp.ic b/storage/innobase/include/rem0cmp.ic
index 52dc7ff5dc9..45e12301a3c 100644
--- a/storage/innobase/include/rem0cmp.ic
+++ b/storage/innobase/include/rem0cmp.ic
@@ -72,5 +72,5 @@ cmp_rec_rec(
 	ulint	match_b		= 0;
 
 	return(cmp_rec_rec_with_match(rec1, rec2, offsets1, offsets2, index,
-				      &match_f, &match_b));
+				      FALSE, &match_f, &match_b));
 }
diff --git a/storage/innobase/include/srv0srv.h b/storage/innobase/include/srv0srv.h
index 3dd4bb961f9..811074b2be8 100644
--- a/storage/innobase/include/srv0srv.h
+++ b/storage/innobase/include/srv0srv.h
@@ -91,6 +91,11 @@ extern ulint	srv_lock_table_size;
 
 extern ulint	srv_n_file_io_threads;
 
+/* The "innodb_stats_method" setting, decides how InnoDB is going
+to treat NULL value when collecting statistics. It is not defined
+as enum type because the configure option takes unsigned integer type. */
+extern ulong	srv_innodb_stats_method;
+
 #ifdef UNIV_LOG_ARCHIVE
 extern ibool	srv_log_archive_on;
 extern ibool	srv_archive_recovery;
@@ -286,6 +291,19 @@ of lower numbers are included. */
 #define SRV_FORCE_NO_LOG_REDO	6	/* do not do the log roll-forward
 					in connection with recovery */
 
+/* Alternatives for srv_innodb_stats_method, which could be changed by
+setting innodb_stats_method */
+enum srv_stats_method_name_enum {
+	SRV_STATS_NULLS_EQUAL,		/* All NULL values are treated as
+					equal. This is the default setting
+					for innodb_stats_method */
+	SRV_STATS_NULLS_UNEQUAL,	/* All NULL values are treated as
+					NOT equal. */
+	SRV_STATS_NULLS_IGNORED		/* NULL values are ignored */
+};
+
+typedef enum srv_stats_method_name_enum		srv_stats_method_name_t;
+
 /*************************************************************************
 Boots Innobase server. */
 
diff --git a/storage/innobase/include/sync0arr.h b/storage/innobase/include/sync0arr.h
index fae26b7a63e..ec48059dbcb 100644
--- a/storage/innobase/include/sync0arr.h
+++ b/storage/innobase/include/sync0arr.h
@@ -93,10 +93,13 @@ sync_arr_wake_threads_if_sema_free(void);
 Prints warnings of long semaphore waits to stderr. */
 
 ibool
-sync_array_print_long_waits(void);
-/*=============================*/
-			/* out: TRUE if fatal semaphore wait threshold
-			was exceeded */
+sync_array_print_long_waits(
+/*========================*/
+				/* out: TRUE if fatal semaphore wait threshold
+				was exceeded */
+	os_thread_id_t*	waiter,	/* out: longest waiting thread */
+	const void**	sema)	/* out: longest-waited-for semaphore */
+	__attribute__((nonnull));
 /************************************************************************
 Validates the integrity of the wait array. Checks
 that the number of reserved cells equals the count variable. */
diff --git a/storage/innobase/include/sync0rw.h b/storage/innobase/include/sync0rw.h
index 008df80a2c7..dd898557d6e 100644
--- a/storage/innobase/include/sync0rw.h
+++ b/storage/innobase/include/sync0rw.h
@@ -1,7 +1,7 @@
 /******************************************************
 The read-write lock (for threads, not for database transactions)
 
-(c) 1995 Innobase Oy
+Copyright (c) 1995, 2011, Oracle and/or its affiliates. All Rights Reserved.
 
 Created 9/11/1995 Heikki Tuuri
 *******************************************************/
@@ -409,6 +409,7 @@ Prints info of a debug struct. */
 void
 rw_lock_debug_print(
 /*================*/
+	FILE*			f,	/* in: output stream */
 	rw_lock_debug_t*	info);	/* in: debug struct */
 #endif /* UNIV_SYNC_DEBUG */
 
diff --git a/storage/innobase/include/trx0rseg.h b/storage/innobase/include/trx0rseg.h
index 46ba010bd1d..22f8aa89181 100644
--- a/storage/innobase/include/trx0rseg.h
+++ b/storage/innobase/include/trx0rseg.h
@@ -121,9 +121,7 @@ struct trx_rseg_struct{
 	ulint		id;	/* rollback segment id == the index of
 				its slot in the trx system file copy */
 	mutex_t		mutex;	/* mutex protecting the fields in this
-				struct except id; NOTE that the latching
-				order must always be kernel mutex ->
-				rseg mutex */
+				struct except id, which is constant */
 	ulint		space;	/* space where the rollback segment is
 				header is placed */
 	ulint		page_no;/* page number of the rollback segment
diff --git a/storage/innobase/include/trx0trx.h b/storage/innobase/include/trx0trx.h
index 97a47d9f46e..4652f45892e 100644
--- a/storage/innobase/include/trx0trx.h
+++ b/storage/innobase/include/trx0trx.h
@@ -198,8 +198,9 @@ which is in the prepared state */
 trx_t *
 trx_get_trx_by_xid(
 /*===============*/
-			/* out: trx or NULL */
-	XID*	xid);	/*  in: X/Open XA transaction identification */
+				/* out: trx or NULL;
+				on match, the trx->xid will be invalidated */
+	const XID*	xid);	/*  in: X/Open XA transaction identifier */
 /**************************************************************************
 If required, flushes the log to disk if we called trx_commit_for_mysql()
 with trx->flush_log_later == TRUE. */
diff --git a/storage/innobase/rem/rem0cmp.c b/storage/innobase/rem/rem0cmp.c
index ca0ec663548..2939c119e2e 100644
--- a/storage/innobase/rem/rem0cmp.c
+++ b/storage/innobase/rem/rem0cmp.c
@@ -720,6 +720,10 @@ cmp_rec_rec_with_match(
 	const ulint*	offsets1,/* in: rec_get_offsets(rec1, index) */
 	const ulint*	offsets2,/* in: rec_get_offsets(rec2, index) */
 	dict_index_t*	index,	/* in: data dictionary index */
+	ibool		nulls_unequal,
+				/* in: TRUE if this is for index statistics
+				cardinality estimation, and innodb_stats_method
+				is "nulls_unequal" or "nulls_ignored" */
 	ulint*		matched_fields, /* in/out: number of already completely
 				matched fields; when the function returns,
 				contains the value the for current
@@ -821,9 +825,13 @@ cmp_rec_rec_with_match(
 			    || rec2_f_len == UNIV_SQL_NULL) {
 
 				if (rec1_f_len == rec2_f_len) {
-
-					goto next_field;
-
+					/* This is limited to stats collection,
+					cannot use it for regular search */
+					if (nulls_unequal) {
+						ret = -1;
+					} else {
+						goto next_field;
+					}
 				} else if (rec2_f_len == UNIV_SQL_NULL) {
 
 					/* We define the SQL null to be the
diff --git a/storage/innobase/row/row0vers.c b/storage/innobase/row/row0vers.c
index f4adfa855df..23aca8c3f2e 100644
--- a/storage/innobase/row/row0vers.c
+++ b/storage/innobase/row/row0vers.c
@@ -593,11 +593,15 @@ row_vers_build_for_semi_consistent_read(
 
 		mutex_enter(&kernel_mutex);
 		version_trx = trx_get_on_id(version_trx_id);
+		if (version_trx
+		    && (version_trx->conc_state == TRX_COMMITTED_IN_MEMORY
+			|| version_trx->conc_state == TRX_NOT_STARTED)) {
+
+			version_trx = NULL;
+		}
 		mutex_exit(&kernel_mutex);
 
-		if (!version_trx
-		    || version_trx->conc_state == TRX_NOT_STARTED
-		    || version_trx->conc_state == TRX_COMMITTED_IN_MEMORY) {
+		if (!version_trx) {
 
 			/* We found a version that belongs to a
 			committed transaction: return it. */
diff --git a/storage/innobase/srv/srv0srv.c b/storage/innobase/srv/srv0srv.c
index 5b1184fb416..3f6f1982992 100644
--- a/storage/innobase/srv/srv0srv.c
+++ b/storage/innobase/srv/srv0srv.c
@@ -218,6 +218,11 @@ ulong	srv_max_buf_pool_modified_pct	= 90;
 /* variable counts amount of data read in total (in bytes) */
 ulint srv_data_read = 0;
 
+/* Internal setting for "innodb_stats_method". Decides how InnoDB treats
+NULL value when collecting statistics. By default, it is set to
+SRV_STATS_NULLS_EQUAL(0), ie. all NULL value are treated equal */
+ulong srv_innodb_stats_method = SRV_STATS_NULLS_EQUAL;
+
 /* here we count the amount of data written in total (in bytes) */
 ulint srv_data_written = 0;
 
@@ -2175,9 +2180,15 @@ srv_error_monitor_thread(
 			os_thread_create */
 {
 	/* number of successive fatal timeouts observed */
-	ulint	fatal_cnt	= 0;
-	dulint	old_lsn;
-	dulint	new_lsn;
+	ulint		fatal_cnt	= 0;
+	dulint		old_lsn;
+	dulint		new_lsn;
+	/* longest waiting thread for a semaphore */
+	os_thread_id_t	waiter		= os_thread_get_curr_id();
+	os_thread_id_t	old_waiter	= waiter;
+	/* the semaphore that is being waited for */
+	const void*	sema		= NULL;
+	const void*	old_sema	= NULL;
 
 	old_lsn = srv_start_lsn;
 
@@ -2219,10 +2230,11 @@ loop:
 	/* In case mutex_exit is not a memory barrier, it is
 	theoretically possible some threads are left waiting though
 	the semaphore is already released. Wake up those threads: */
-	
+
 	sync_arr_wake_threads_if_sema_free();
 
-	if (sync_array_print_long_waits()) {
+	if (sync_array_print_long_waits(&waiter, &sema)
+	    && sema == old_sema && os_thread_eq(waiter, old_waiter)) {
 		fatal_cnt++;
 		if (fatal_cnt > 10) {
 
@@ -2237,6 +2249,8 @@ loop:
 		}
 	} else {
 		fatal_cnt = 0;
+		old_waiter = waiter;
+		old_sema = sema;
 	}
 
 	/* Flush stderr so that a database user gets the output
diff --git a/storage/innobase/sync/sync0arr.c b/storage/innobase/sync/sync0arr.c
index 154593a9035..93a7398f252 100644
--- a/storage/innobase/sync/sync0arr.c
+++ b/storage/innobase/sync/sync0arr.c
@@ -1,7 +1,7 @@
 /******************************************************
 The wait array used in synchronization primitives
 
-(c) 1995 Innobase Oy
+Copyright (c) 1995, 2011, Oracle and/or its affiliates. All Rights Reserved.
 
 Created 9/5/1995 Heikki Tuuri
 *******************************************************/
@@ -709,7 +709,7 @@ print:
 					fprintf(stderr, "rw-lock %p ",
 						(void*) lock);
 					sync_array_cell_print(stderr, cell);
-					rw_lock_debug_print(debug);
+					rw_lock_debug_print(stderr, debug);
 					return(TRUE);
 				}
 			}
@@ -916,10 +916,12 @@ sync_arr_wake_threads_if_sema_free(void)
 Prints warnings of long semaphore waits to stderr. */
 
 ibool
-sync_array_print_long_waits(void)
-/*=============================*/
-			/* out: TRUE if fatal semaphore wait threshold
-			was exceeded */
+sync_array_print_long_waits(
+/*========================*/
+				/* out: TRUE if fatal semaphore wait threshold
+				was exceeded */
+	os_thread_id_t*	waiter,	/* out: longest waiting thread */
+	const void**	sema)	/* out: longest-waited-for semaphore */
 {
 	sync_cell_t*	cell;
 	ibool		old_val;
@@ -927,24 +929,40 @@ sync_array_print_long_waits(void)
 	ulint		i;
 	ulint		fatal_timeout = srv_fatal_semaphore_wait_threshold;
 	ibool		fatal = FALSE;
+	double		longest_diff = 0;
 
 	for (i = 0; i < sync_primary_wait_array->n_cells; i++) {
 
+		double	diff;
+		void*	wait_object;
+
 		cell = sync_array_get_nth_cell(sync_primary_wait_array, i);
 
-		if (cell->wait_object != NULL && cell->waiting
-		    && difftime(time(NULL), cell->reservation_time) > 240) {
+		wait_object = cell->wait_object;
+
+		if (wait_object == NULL || !cell->waiting) {
+
+			continue;
+		}
+
+		diff = difftime(time(NULL), cell->reservation_time);
+
+		if (diff > 240) {
 			fputs("InnoDB: Warning: a long semaphore wait:\n",
 			      stderr);
 			sync_array_cell_print(stderr, cell);
 			noticed = TRUE;
 		}
 
-		if (cell->wait_object != NULL && cell->waiting
-		    && difftime(time(NULL), cell->reservation_time)
-		    > fatal_timeout) {
+		if (diff > fatal_timeout) {
 			fatal = TRUE;
 		}
+
+		if (diff > longest_diff) {
+			longest_diff = diff;
+			*sema = wait_object;
+			*waiter = cell->thread;
+		}
 	}
 
 	if (noticed) {
diff --git a/storage/innobase/sync/sync0rw.c b/storage/innobase/sync/sync0rw.c
index 0b05fb826ac..ef4c07e8c26 100644
--- a/storage/innobase/sync/sync0rw.c
+++ b/storage/innobase/sync/sync0rw.c
@@ -1,7 +1,7 @@
 /******************************************************
 The read-write lock (for thread synchronization)
 
-(c) 1995 Innobase Oy
+Copyright (c) 1995, 2011, Oracle and/or its affiliates. All Rights Reserved.
 
 Created 9/11/1995 Heikki Tuuri
 *******************************************************/
@@ -830,7 +830,7 @@ rw_lock_list_print_info(
 
 			info = UT_LIST_GET_FIRST(lock->debug_list);
 			while (info != NULL) {
-				rw_lock_debug_print(info);
+				rw_lock_debug_print(file, info);
 				info = UT_LIST_GET_NEXT(list, info);
 			}
 		}
@@ -870,7 +870,7 @@ rw_lock_print(
 
 		info = UT_LIST_GET_FIRST(lock->debug_list);
 		while (info != NULL) {
-			rw_lock_debug_print(info);
+			rw_lock_debug_print(stderr, info);
 			info = UT_LIST_GET_NEXT(list, info);
 		}
 	}
@@ -882,28 +882,29 @@ Prints info of a debug struct. */
 void
 rw_lock_debug_print(
 /*================*/
+	FILE*			f,	/* in: output stream */
 	rw_lock_debug_t*	info)	/* in: debug struct */
 {
 	ulint	rwt;
 
 	rwt	  = info->lock_type;
 
-	fprintf(stderr, "Locked: thread %lu file %s line %lu  ",
+	fprintf(f, "Locked: thread %lu file %s line %lu  ",
 		(ulong) os_thread_pf(info->thread_id), info->file_name,
 		(ulong) info->line);
 	if (rwt == RW_LOCK_SHARED) {
-		fputs("S-LOCK", stderr);
+		fputs("S-LOCK", f);
 	} else if (rwt == RW_LOCK_EX) {
-		fputs("X-LOCK", stderr);
+		fputs("X-LOCK", f);
 	} else if (rwt == RW_LOCK_WAIT_EX) {
-		fputs("WAIT X-LOCK", stderr);
+		fputs("WAIT X-LOCK", f);
 	} else {
 		ut_error;
 	}
 	if (info->pass != 0) {
-		fprintf(stderr, " pass value %lu", (ulong) info->pass);
+		fprintf(f, " pass value %lu", (ulong) info->pass);
 	}
-	putc('\n', stderr);
+	putc('\n', f);
 }
 
 /*******************************************************************
diff --git a/storage/innobase/trx/trx0trx.c b/storage/innobase/trx/trx0trx.c
index 21f75e0818f..a82d7f452fc 100644
--- a/storage/innobase/trx/trx0trx.c
+++ b/storage/innobase/trx/trx0trx.c
@@ -2041,14 +2041,15 @@ which is in the prepared state */
 trx_t*
 trx_get_trx_by_xid(
 /*===============*/
-			/* out: trx or NULL */
-	XID*	xid)	/* in: X/Open XA transaction identification */
+				/* out: trx or NULL;
+				on match, the trx->xid will be invalidated */
+	const XID*	xid)	/* in: X/Open XA transaction identifier */
 {
 	trx_t*	trx;
 
 	if (xid == NULL) {
 
-		return (NULL);
+		return(NULL);
 	}
 
 	mutex_enter(&kernel_mutex);
@@ -2061,10 +2062,16 @@ trx_get_trx_by_xid(
 		of gtrid_lenght+bqual_length bytes should be
 		the same */
 
-		if (xid->gtrid_length == trx->xid.gtrid_length
+		if (trx->conc_state == TRX_PREPARED
+		    && xid->gtrid_length == trx->xid.gtrid_length
 		    && xid->bqual_length == trx->xid.bqual_length
 		    && memcmp(xid->data, trx->xid.data,
 			      xid->gtrid_length + xid->bqual_length) == 0) {
+
+			/* Invalidate the XID, so that subsequent calls
+			will not find it. */
+			memset(&trx->xid, 0, sizeof(trx->xid));
+			trx->xid.formatID = -1;
 			break;
 		}
 
@@ -2073,14 +2080,5 @@ trx_get_trx_by_xid(
 
 	mutex_exit(&kernel_mutex);
 
-	if (trx) {
-		if (trx->conc_state != TRX_PREPARED) {
-
-			return(NULL);
-		}
-
-		return(trx);
-	} else {
-		return(NULL);
-	}
+	return(trx);
 }
diff --git a/storage/innodb_plugin/ChangeLog b/storage/innodb_plugin/ChangeLog
index bf003b810d2..100cf3690ce 100644
--- a/storage/innodb_plugin/ChangeLog
+++ b/storage/innodb_plugin/ChangeLog
@@ -1,3 +1,89 @@
+2011-03-30	The InnoDB Team
+
+	* srv/srv0srv.c, sync/sync0arr.h, sync/sync0arr.c:
+	Fix Bug#11877216 InnoDB too eager to commit suicide on a busy server
+
+2011-03-15	The InnoDB Team
+
+	* btr/btr0cur.c, page/page0zip.c:
+	Fix Bug#11849231 inflateInit() invoked without initializing all memory
+
+2011-02-28	The InnoDB Team
+
+	* btr/btr0sea.c, buf/buf0buf.c, buf/buf0lru.c:
+	Fix Bug#58549 Race condition in buf_LRU_drop_page_hash_for_tablespace()
+	and compressed tables
+
+2011-02-15	The InnoDB Team
+
+	* sync/sync0rw.c, innodb_bug59307.test:
+	Bug#59307 Valgrind: uninitialized value in
+	rw_lock_set_writer_id_and_recursion_flag()
+
+2011-02-14	The InnoDB Team
+
+	* handler/handler0alter.cc:
+	Bug#59749 Enabling concurrent reads while creating non-primary
+	unique index gives failures
+
+2011-01-31	The InnoDB Team
+
+	* btr/btr0cur.c, include/row0upd.h,
+	row/row0purge.c, row/row0umod.c, row/row0upd.c:
+	Bug#59230 assert 0 row_upd_changes_ord_field_binary()
+	in post-crash rollback or purge
+
+2011-01-27	The InnoDB Team
+
+	* btr/btr0cur.c:
+	Bug#59465 btr_estimate_number_of_different_key_vals use
+	incorrect offset for external_size
+
+2011-01-27	The InnoDB Team
+
+	* include/trx0trx.h, trx/trx0trx.c:
+	Bug#59440 Race condition in XA ROLLBACK and XA COMMIT
+	after server restart
+
+2011-01-25	The InnoDB Team
+
+	* row/row0upd.c:
+	Bug#59585 Fix 58912 introduces compiler warning
+	due to potentially uninitialized variable
+
+2011-01-25	The InnoDB Team
+
+	* mtr/mtr0log.c:
+	Bug#59486 Incorrect usage of UNIV_UNLIKELY() in mlog_parse_string()
+
+2011-01-25	The InnoDB Team
+
+	* row/row0vers.c:
+	Fix Bug#59464 Race condition in row_vers_build_for_semi_consistent_read
+
+2011-01-25	The InnoDB Team
+
+	* btr/btr0btr.c, btr/btr0cur.c, btr/btr0sea.c,
+	buf/buf0buddy.c, buf/buf0buf.c, buf/buf0lru.c,
+	include/buf0buf.h, include/buf0buf.ic, include/buf0lru.h,
+	mem/mem0mem.c, page/page0zip.c:
+	Fix Bug#59707 Unused compression-related parameters
+	in buffer pool functions
+
+2011-01-18	The InnoDB Team
+
+	* include/sync0rw.h, sync/sync0arr.c, sync/sync0rw.c:
+	Fix Bug#59579 rw_lock_debug_print outputs to stderr, not to
+	SHOW ENGINE INNODB STATUS
+
+2011-01-14	The InnoDB Team
+	* btr/btr0cur.c, dict/dict0dict.c, handler/ha_innodb.cc,
+	include/btr0cur.h, include/dict0mem.h, include/rem0cmp.h,
+	include/rem0cmp.ic, include/srv0srv.h, rem/rem0cmp.c,
+	srv/srv0srv.c, innodb_bug30423.test:
+	Fix Bug#30423 InnoDBs treatment of NULL in index stats causes
+	bad "rows examined" estimates
+
 2011-01-06	The InnoDB Team
 	* row/row0merge.c:
 	Fix Bug#59312 Examine MAX_FULL_NAME_LEN in InnoDB to address
diff --git a/storage/innodb_plugin/btr/btr0btr.c b/storage/innodb_plugin/btr/btr0btr.c
index 32e2caecdb8..46810c011c4 100644
--- a/storage/innodb_plugin/btr/btr0btr.c
+++ b/storage/innodb_plugin/btr/btr0btr.c
@@ -42,6 +42,560 @@ Created 6/2/1994 Heikki Tuuri
 #include "ibuf0ibuf.h"
 #include "trx0trx.h"
 
+#ifdef UNIV_BLOB_DEBUG
+# include "srv0srv.h"
+# include "ut0rbt.h"
+
+/** TRUE when messages about index->blobs modification are enabled. */
+static ibool btr_blob_dbg_msg;
+
+/** Issue a message about an operation on index->blobs.
+@param op	operation
+@param b	the entry being subjected to the operation
+@param ctx	the context of the operation */
+#define btr_blob_dbg_msg_issue(op, b, ctx)			\
+	fprintf(stderr, op " %u:%u:%u->%u %s(%u,%u,%u)\n",	\
+		(b)->ref_page_no, (b)->ref_heap_no,		\
+		(b)->ref_field_no, (b)->blob_page_no, ctx,	\
+		(b)->owner, (b)->always_owner, (b)->del)
+
+/** Insert to index->blobs a reference to an off-page column.
+@param index	the index tree
+@param b	the reference
+@param ctx	context (for logging) */
+UNIV_INTERN
+void
+btr_blob_dbg_rbt_insert(
+/*====================*/
+	dict_index_t*		index,	/*!< in/out: index tree */
+	const btr_blob_dbg_t*	b,	/*!< in: the reference */
+	const char*		ctx)	/*!< in: context (for logging) */
+{
+	if (btr_blob_dbg_msg) {
+		btr_blob_dbg_msg_issue("insert", b, ctx);
+	}
+	mutex_enter(&index->blobs_mutex);
+	rbt_insert(index->blobs, b, b);
+	mutex_exit(&index->blobs_mutex);
+}
+
+/** Remove from index->blobs a reference to an off-page column.
+@param index	the index tree
+@param b	the reference
+@param ctx	context (for logging) */
+UNIV_INTERN
+void
+btr_blob_dbg_rbt_delete(
+/*====================*/
+	dict_index_t*		index,	/*!< in/out: index tree */
+	const btr_blob_dbg_t*	b,	/*!< in: the reference */
+	const char*		ctx)	/*!< in: context (for logging) */
+{
+	if (btr_blob_dbg_msg) {
+		btr_blob_dbg_msg_issue("delete", b, ctx);
+	}
+	mutex_enter(&index->blobs_mutex);
+	ut_a(rbt_delete(index->blobs, b));
+	mutex_exit(&index->blobs_mutex);
+}
+
+/**************************************************************//**
+Comparator for items (btr_blob_dbg_t) in index->blobs.
+The key in index->blobs is (ref_page_no, ref_heap_no, ref_field_no).
+@return negative, 0 or positive if *a<*b, *a=*b, *a>*b */
+static
+int
+btr_blob_dbg_cmp(
+/*=============*/
+	const void*	a,	/*!< in: first btr_blob_dbg_t to compare */
+	const void*	b)	/*!< in: second btr_blob_dbg_t to compare */
+{
+	const btr_blob_dbg_t*	aa	= a;
+	const btr_blob_dbg_t*	bb	= b;
+
+	ut_ad(aa != NULL);
+	ut_ad(bb != NULL);
+
+	if (aa->ref_page_no != bb->ref_page_no) {
+		return(aa->ref_page_no < bb->ref_page_no ? -1 : 1);
+	}
+	if (aa->ref_heap_no != bb->ref_heap_no) {
+		return(aa->ref_heap_no < bb->ref_heap_no ? -1 : 1);
+	}
+	if (aa->ref_field_no != bb->ref_field_no) {
+		return(aa->ref_field_no < bb->ref_field_no ? -1 : 1);
+	}
+	return(0);
+}
+
+/**************************************************************//**
+Add a reference to an off-page column to the index->blobs map. */
+UNIV_INTERN
+void
+btr_blob_dbg_add_blob(
+/*==================*/
+	const rec_t*	rec,		/*!< in: clustered index record */
+	ulint		field_no,	/*!< in: off-page column number */
+	ulint		page_no,	/*!< in: start page of the column */
+	dict_index_t*	index,		/*!< in/out: index tree */
+	const char*	ctx)		/*!< in: context (for logging) */
+{
+	btr_blob_dbg_t	b;
+	const page_t*	page	= page_align(rec);
+
+	ut_a(index->blobs);
+
+	b.blob_page_no = page_no;
+	b.ref_page_no = page_get_page_no(page);
+	b.ref_heap_no = page_rec_get_heap_no(rec);
+	b.ref_field_no = field_no;
+	ut_a(b.ref_field_no >= index->n_uniq);
+	b.always_owner = b.owner = TRUE;
+	b.del = FALSE;
+	ut_a(!rec_get_deleted_flag(rec, page_is_comp(page)));
+	btr_blob_dbg_rbt_insert(index, &b, ctx);
+}
+
+/**************************************************************//**
+Add to index->blobs any references to off-page columns from a record.
+@return number of references added */
+UNIV_INTERN
+ulint
+btr_blob_dbg_add_rec(
+/*=================*/
+	const rec_t*	rec,	/*!< in: record */
+	dict_index_t*	index,	/*!< in/out: index */
+	const ulint*	offsets,/*!< in: offsets */
+	const char*	ctx)	/*!< in: context (for logging) */
+{
+	ulint		count	= 0;
+	ulint		i;
+	btr_blob_dbg_t	b;
+	ibool		del;
+
+	ut_ad(rec_offs_validate(rec, index, offsets));
+
+	if (!rec_offs_any_extern(offsets)) {
+		return(0);
+	}
+
+	b.ref_page_no = page_get_page_no(page_align(rec));
+	b.ref_heap_no = page_rec_get_heap_no(rec);
+	del = (rec_get_deleted_flag(rec, rec_offs_comp(offsets)) != 0);
+
+	for (i = 0; i < rec_offs_n_fields(offsets); i++) {
+		if (rec_offs_nth_extern(offsets, i)) {
+			ulint		len;
+			const byte*	field_ref = rec_get_nth_field(
+				rec, offsets, i, &len);
+
+			ut_a(len != UNIV_SQL_NULL);
+			ut_a(len >= BTR_EXTERN_FIELD_REF_SIZE);
+			field_ref += len - BTR_EXTERN_FIELD_REF_SIZE;
+
+			if (!memcmp(field_ref, field_ref_zero,
+				    BTR_EXTERN_FIELD_REF_SIZE)) {
+				/* the column has not been stored yet */
+				continue;
+			}
+
+			b.ref_field_no = i;
+			b.blob_page_no = mach_read_from_4(
+				field_ref + BTR_EXTERN_PAGE_NO);
+			ut_a(b.ref_field_no >= index->n_uniq);
+			b.always_owner = b.owner
+				= !(field_ref[BTR_EXTERN_LEN]
+				    & BTR_EXTERN_OWNER_FLAG);
+			b.del = del;
+
+			btr_blob_dbg_rbt_insert(index, &b, ctx);
+			count++;
+		}
+	}
+
+	return(count);
+}
+
+/**************************************************************//**
+Display the references to off-page columns.
+This function is to be called from a debugger,
+for example when a breakpoint on ut_dbg_assertion_failed is hit. */
+UNIV_INTERN
+void
+btr_blob_dbg_print(
+/*===============*/
+	const dict_index_t*	index)	/*!< in: index tree */
+{
+	const ib_rbt_node_t*	node;
+
+	if (!index->blobs) {
+		return;
+	}
+
+	/* We intentionally do not acquire index->blobs_mutex here.
+	This function is to be called from a debugger, and the caller
+	should make sure that the index->blobs_mutex is held. */
+
+	for (node = rbt_first(index->blobs);
+	     node != NULL; node = rbt_next(index->blobs, node)) {
+		const btr_blob_dbg_t*	b
+			= rbt_value(btr_blob_dbg_t, node);
+		fprintf(stderr, "%u:%u:%u->%u%s%s%s\n",
+			b->ref_page_no, b->ref_heap_no, b->ref_field_no,
+			b->blob_page_no,
+			b->owner ? "" : "(disowned)",
+			b->always_owner ? "" : "(has disowned)",
+			b->del ? "(deleted)" : "");
+	}
+}
+
+/**************************************************************//**
+Remove from index->blobs any references to off-page columns from a record.
+@return number of references removed */
+UNIV_INTERN
+ulint
+btr_blob_dbg_remove_rec(
+/*====================*/
+	const rec_t*	rec,	/*!< in: record */
+	dict_index_t*	index,	/*!< in/out: index */
+	const ulint*	offsets,/*!< in: offsets */
+	const char*	ctx)	/*!< in: context (for logging) */
+{
+	ulint		i;
+	ulint		count	= 0;
+	btr_blob_dbg_t	b;
+
+	ut_ad(rec_offs_validate(rec, index, offsets));
+
+	if (!rec_offs_any_extern(offsets)) {
+		return(0);
+	}
+
+	b.ref_page_no = page_get_page_no(page_align(rec));
+	b.ref_heap_no = page_rec_get_heap_no(rec);
+
+	for (i = 0; i < rec_offs_n_fields(offsets); i++) {
+		if (rec_offs_nth_extern(offsets, i)) {
+			ulint		len;
+			const byte*	field_ref = rec_get_nth_field(
+				rec, offsets, i, &len);
+
+			ut_a(len != UNIV_SQL_NULL);
+			ut_a(len >= BTR_EXTERN_FIELD_REF_SIZE);
+			field_ref += len - BTR_EXTERN_FIELD_REF_SIZE;
+
+			b.ref_field_no = i;
+			b.blob_page_no = mach_read_from_4(
+				field_ref + BTR_EXTERN_PAGE_NO);
+
+			switch (b.blob_page_no) {
+			case 0:
+				/* The column has not been stored yet.
+				The BLOB pointer must be all zero.
+				There cannot be a BLOB starting at
+				page 0, because page 0 is reserved for
+				the tablespace header. */
+				ut_a(!memcmp(field_ref, field_ref_zero,
+					     BTR_EXTERN_FIELD_REF_SIZE));
+				/* fall through */
+			case FIL_NULL:
+				/* the column has been freed already */
+				continue;
+			}
+
+			btr_blob_dbg_rbt_delete(index, &b, ctx);
+			count++;
+		}
+	}
+
+	return(count);
+}
+
+/**************************************************************//**
+Check that there are no references to off-page columns from or to
+the given page. Invoked when freeing or clearing a page.
+@return TRUE when no orphan references exist */
+UNIV_INTERN
+ibool
+btr_blob_dbg_is_empty(
+/*==================*/
+	dict_index_t*	index,		/*!< in: index */
+	ulint		page_no)	/*!< in: page number */
+{
+	const ib_rbt_node_t*	node;
+	ibool			success	= TRUE;
+
+	if (!index->blobs) {
+		return(success);
+	}
+
+	mutex_enter(&index->blobs_mutex);
+
+	for (node = rbt_first(index->blobs);
+	     node != NULL; node = rbt_next(index->blobs, node)) {
+		const btr_blob_dbg_t*	b
+			= rbt_value(btr_blob_dbg_t, node);
+
+		if (b->ref_page_no != page_no && b->blob_page_no != page_no) {
+			continue;
+		}
+
+		fprintf(stderr,
+			"InnoDB: orphan BLOB ref%s%s%s %u:%u:%u->%u\n",
+			b->owner ? "" : "(disowned)",
+			b->always_owner ? "" : "(has disowned)",
+			b->del ? "(deleted)" : "",
+			b->ref_page_no, b->ref_heap_no, b->ref_field_no,
+			b->blob_page_no);
+
+		if (b->blob_page_no != page_no || b->owner || !b->del) {
+			success = FALSE;
+		}
+	}
+
+	mutex_exit(&index->blobs_mutex);
+	return(success);
+}
+
+/**************************************************************//**
+Count and process all references to off-page columns on a page.
+@return number of references processed */
+UNIV_INTERN
+ulint
+btr_blob_dbg_op(
+/*============*/
+	const page_t*		page,	/*!< in: B-tree leaf page */
+	const rec_t*		rec,	/*!< in: record to start from
+					(NULL to process the whole page) */
+	dict_index_t*		index,	/*!< in/out: index */
+	const char*		ctx,	/*!< in: context (for logging) */
+	const btr_blob_dbg_op_f	op)	/*!< in: operation on records */
+{
+	ulint		count	= 0;
+	mem_heap_t*	heap	= NULL;
+	ulint		offsets_[REC_OFFS_NORMAL_SIZE];
+	ulint*		offsets	= offsets_;
+	rec_offs_init(offsets_);
+
+	ut_a(fil_page_get_type(page) == FIL_PAGE_INDEX);
+	ut_a(!rec || page_align(rec) == page);
+
+	if (!index->blobs || !page_is_leaf(page)
+	    || !dict_index_is_clust(index)) {
+		return(0);
+	}
+
+	if (rec == NULL) {
+		rec = page_get_infimum_rec(page);
+	}
+
+	do {
+		offsets = rec_get_offsets(rec, index, offsets,
+					  ULINT_UNDEFINED, &heap);
+		count += op(rec, index, offsets, ctx);
+		rec = page_rec_get_next_const(rec);
+	} while (!page_rec_is_supremum(rec));
+
+	if (UNIV_LIKELY_NULL(heap)) {
+		mem_heap_free(heap);
+	}
+
+	return(count);
+}
+
+/**************************************************************//**
+Count and add to index->blobs any references to off-page columns
+from records on a page.
+@return number of references added */
+UNIV_INTERN
+ulint
+btr_blob_dbg_add(
+/*=============*/
+	const page_t*	page,	/*!< in: rewritten page */
+	dict_index_t*	index,	/*!< in/out: index */
+	const char*	ctx)	/*!< in: context (for logging) */
+{
+	btr_blob_dbg_assert_empty(index, page_get_page_no(page));
+
+	return(btr_blob_dbg_op(page, NULL, index, ctx, btr_blob_dbg_add_rec));
+}
+
+/**************************************************************//**
+Count and remove from index->blobs any references to off-page columns
+from records on a page.
+Used when reorganizing a page, before copying the records.
+@return number of references removed */
+UNIV_INTERN
+ulint
+btr_blob_dbg_remove(
+/*================*/
+	const page_t*	page,	/*!< in: b-tree page */
+	dict_index_t*	index,	/*!< in/out: index */
+	const char*	ctx)	/*!< in: context (for logging) */
+{
+	ulint	count;
+
+	count = btr_blob_dbg_op(page, NULL, index, ctx,
+				btr_blob_dbg_remove_rec);
+
+	/* Check that no references exist. */
+	btr_blob_dbg_assert_empty(index, page_get_page_no(page));
+
+	return(count);
+}
+
+/**************************************************************//**
+Restore in index->blobs any references to off-page columns
+Used when page reorganize fails due to compressed page overflow. */
+UNIV_INTERN
+void
+btr_blob_dbg_restore(
+/*=================*/
+	const page_t*	npage,	/*!< in: page that failed to compress  */
+	const page_t*	page,	/*!< in: copy of original page */
+	dict_index_t*	index,	/*!< in/out: index */
+	const char*	ctx)	/*!< in: context (for logging) */
+{
+	ulint	removed;
+	ulint	added;
+
+	ut_a(page_get_page_no(npage) == page_get_page_no(page));
+	ut_a(page_get_space_id(npage) == page_get_space_id(page));
+
+	removed = btr_blob_dbg_remove(npage, index, ctx);
+	added = btr_blob_dbg_add(page, index, ctx);
+	ut_a(added == removed);
+}
+
+/**************************************************************//**
+Modify the 'deleted' flag of a record. */
+UNIV_INTERN
+void
+btr_blob_dbg_set_deleted_flag(
+/*==========================*/
+	const rec_t*		rec,	/*!< in: record */
+	dict_index_t*		index,	/*!< in/out: index */
+	const ulint*		offsets,/*!< in: rec_get_offs(rec, index) */
+	ibool			del)	/*!< in: TRUE=deleted, FALSE=exists */
+{
+	const ib_rbt_node_t*	node;
+	btr_blob_dbg_t		b;
+	btr_blob_dbg_t*		c;
+	ulint			i;
+
+	ut_ad(rec_offs_validate(rec, index, offsets));
+	ut_a(dict_index_is_clust(index));
+	ut_a(del == !!del);/* must be FALSE==0 or TRUE==1 */
+
+	if (!rec_offs_any_extern(offsets) || !index->blobs) {
+
+		return;
+	}
+
+	b.ref_page_no = page_get_page_no(page_align(rec));
+	b.ref_heap_no = page_rec_get_heap_no(rec);
+
+	for (i = 0; i < rec_offs_n_fields(offsets); i++) {
+		if (rec_offs_nth_extern(offsets, i)) {
+			ulint		len;
+			const byte*	field_ref = rec_get_nth_field(
+				rec, offsets, i, &len);
+
+			ut_a(len != UNIV_SQL_NULL);
+			ut_a(len >= BTR_EXTERN_FIELD_REF_SIZE);
+			field_ref += len - BTR_EXTERN_FIELD_REF_SIZE;
+
+			b.ref_field_no = i;
+			b.blob_page_no = mach_read_from_4(
+				field_ref + BTR_EXTERN_PAGE_NO);
+
+			switch (b.blob_page_no) {
+			case 0:
+				ut_a(memcmp(field_ref, field_ref_zero,
+					    BTR_EXTERN_FIELD_REF_SIZE));
+				/* page number 0 is for the
+				page allocation bitmap */
+			case FIL_NULL:
+				/* the column has been freed already */
+				ut_error;
+			}
+
+			mutex_enter(&index->blobs_mutex);
+			node = rbt_lookup(index->blobs, &b);
+			ut_a(node);
+
+			c = rbt_value(btr_blob_dbg_t, node);
+			/* The flag should be modified. */
+			c->del = del;
+			if (btr_blob_dbg_msg) {
+				b = *c;
+				mutex_exit(&index->blobs_mutex);
+				btr_blob_dbg_msg_issue("del_mk", &b, "");
+			} else {
+				mutex_exit(&index->blobs_mutex);
+			}
+		}
+	}
+}
+
+/**************************************************************//**
+Change the ownership of an off-page column. */
+UNIV_INTERN
+void
+btr_blob_dbg_owner(
+/*===============*/
+	const rec_t*		rec,	/*!< in: record */
+	dict_index_t*		index,	/*!< in/out: index */
+	const ulint*		offsets,/*!< in: rec_get_offs(rec, index) */
+	ulint			i,	/*!< in: ith field in rec */
+	ibool			own)	/*!< in: TRUE=owned, FALSE=disowned */
+{
+	const ib_rbt_node_t*	node;
+	btr_blob_dbg_t		b;
+	const byte*		field_ref;
+	ulint			len;
+
+	ut_ad(rec_offs_validate(rec, index, offsets));
+	ut_a(rec_offs_nth_extern(offsets, i));
+
+	field_ref = rec_get_nth_field(rec, offsets, i, &len);
+	ut_a(len != UNIV_SQL_NULL);
+	ut_a(len >= BTR_EXTERN_FIELD_REF_SIZE);
+	field_ref += len - BTR_EXTERN_FIELD_REF_SIZE;
+
+	b.ref_page_no = page_get_page_no(page_align(rec));
+	b.ref_heap_no = page_rec_get_heap_no(rec);
+	b.ref_field_no = i;
+	b.owner = !(field_ref[BTR_EXTERN_LEN] & BTR_EXTERN_OWNER_FLAG);
+	b.blob_page_no = mach_read_from_4(field_ref + BTR_EXTERN_PAGE_NO);
+
+	ut_a(b.owner == own);
+
+	mutex_enter(&index->blobs_mutex);
+	node = rbt_lookup(index->blobs, &b);
+	/* row_ins_clust_index_entry_by_modify() invokes
+	btr_cur_unmark_extern_fields() also for the newly inserted
+	references, which are all zero bytes until the columns are stored.
+	The node lookup must fail if and only if that is the case. */
+	ut_a(!memcmp(field_ref, field_ref_zero, BTR_EXTERN_FIELD_REF_SIZE)
+	     == !node);
+
+	if (node) {
+		btr_blob_dbg_t*	c = rbt_value(btr_blob_dbg_t, node);
+		/* Some code sets ownership from TRUE to TRUE.
+		We do not allow changing ownership from FALSE to FALSE. */
+		ut_a(own || c->owner);
+
+		c->owner = own;
+		if (!own) {
+			c->always_owner = FALSE;
+		}
+	}
+
+	mutex_exit(&index->blobs_mutex);
+}
+#endif /* UNIV_BLOB_DEBUG */
+
 /*
 Latching strategy of the InnoDB B-tree
 --------------------------------------
@@ -296,6 +850,7 @@ btr_page_create(
 	page_t*		page = buf_block_get_frame(block);
 
 	ut_ad(mtr_memo_contains(mtr, block, MTR_MEMO_PAGE_X_FIX));
+	btr_blob_dbg_assert_empty(index, buf_block_get_page_no(block));
 
 	if (UNIV_LIKELY_NULL(page_zip)) {
 		page_create_zip(block, index, level, mtr);
@@ -489,6 +1044,7 @@ btr_page_free_low(
 	modify clock */
 
 	buf_block_modify_clock_inc(block);
+	btr_blob_dbg_assert_empty(index, buf_block_get_page_no(block));
 
 	if (dict_index_is_ibuf(index)) {
 
@@ -773,6 +1329,13 @@ btr_create(
 		block = buf_page_get(space, zip_size, page_no,
 				     RW_X_LATCH, mtr);
 	} else {
+#ifdef UNIV_BLOB_DEBUG
+		if ((type & DICT_CLUSTERED) && !index->blobs) {
+			mutex_create(&index->blobs_mutex, SYNC_ANY_LATCH);
+			index->blobs = rbt_create(sizeof(btr_blob_dbg_t),
+						  btr_blob_dbg_cmp);
+		}
+#endif /* UNIV_BLOB_DEBUG */
 		block = fseg_create(space, 0,
 				    PAGE_HEADER + PAGE_BTR_SEG_TOP, mtr);
 	}
@@ -979,7 +1542,7 @@ btr_page_reorganize_low(
 	log_mode = mtr_set_log_mode(mtr, MTR_LOG_NONE);
 
 #ifndef UNIV_HOTBACKUP
-	temp_block = buf_block_alloc(0);
+	temp_block = buf_block_alloc();
 #else /* !UNIV_HOTBACKUP */
 	ut_ad(block == back_block1);
 	temp_block = back_block2;
@@ -996,6 +1559,7 @@ btr_page_reorganize_low(
 
 	block->check_index_page_at_flush = TRUE;
 #endif /* !UNIV_HOTBACKUP */
+	btr_blob_dbg_remove(page, index, "btr_page_reorganize");
 
 	/* Recreate the page: note that global data on page (possible
 	segment headers, next page-field, etc.) is preserved intact */
@@ -1024,6 +1588,8 @@ btr_page_reorganize_low(
 	    (!page_zip_compress(page_zip, page, index, NULL))) {
 
 		/* Restore the old page and exit. */
+		btr_blob_dbg_restore(page, temp_page, index,
+				     "btr_page_reorganize_compress_fail");
 
 #if defined UNIV_DEBUG || defined UNIV_ZIP_DEBUG
 		/* Check that the bytes that we skip are identical. */
@@ -1157,6 +1723,7 @@ btr_page_empty(
 #endif /* UNIV_ZIP_DEBUG */
 
 	btr_search_drop_page_hash_index(block);
+	btr_blob_dbg_remove(page, index, "btr_page_empty");
 
 	/* Recreate the page: note that global data on page (possible
 	segment headers, next page-field, etc.) is preserved intact */
@@ -2497,6 +3064,7 @@ btr_lift_page_up(
 						       index);
 	}
 
+	btr_blob_dbg_remove(page, index, "btr_lift_page_up");
 	lock_update_copy_and_discard(father_block, block);
 
 	/* Go upward to root page, decrementing levels by one. */
@@ -2758,6 +3326,7 @@ err_exit:
 		lock_update_merge_right(merge_block, orig_succ, block);
 	}
 
+	btr_blob_dbg_remove(page, index, "btr_compress");
 	mem_heap_free(heap);
 
 	if (!dict_index_is_clust(index) && page_is_leaf(merge_page)) {
@@ -2988,6 +3557,8 @@ btr_discard_page(
 				    block);
 	}
 
+	btr_blob_dbg_remove(page, index, "btr_discard_page");
+
 	/* Free the file page */
 	btr_page_free(index, block, mtr);
 
diff --git a/storage/innodb_plugin/btr/btr0cur.c b/storage/innodb_plugin/btr/btr0cur.c
index c57255a25ae..d7b5ed0d135 100644
--- a/storage/innodb_plugin/btr/btr0cur.c
+++ b/storage/innodb_plugin/btr/btr0cur.c
@@ -100,6 +100,18 @@ can be released by page reorganize, then it is reorganized */
 /*--------------------------------------*/
 #define BTR_BLOB_HDR_SIZE		8	/*!< Size of a BLOB
 						part header, in bytes */
+
+/** Estimated table level stats from sampled value.
+@param value		sampled stats
+@param index		index being sampled
+@param sample		number of sampled rows
+@param ext_size		external stored data size
+@param not_empty	table not empty
+@return estimated table wide stats from sampled value */
+#define BTR_TABLE_STATS_FROM_SAMPLE(value, index, sample, ext_size, not_empty)\
+	(((value) * (ib_int64_t) index->stat_n_leaf_pages		\
+	  + (sample) - 1 + (ext_size) + (not_empty)) / ((sample) + (ext_size)))
+
 /* @} */
 #endif /* !UNIV_HOTBACKUP */
 
@@ -174,7 +186,7 @@ static
 ulint
 btr_rec_get_externally_stored_len(
 /*==============================*/
-	rec_t*		rec,	/*!< in: record */
+	const rec_t*	rec,	/*!< in: record */
 	const ulint*	offsets);/*!< in: array returned by rec_get_offsets() */
 #endif /* !UNIV_HOTBACKUP */
 
@@ -1756,8 +1768,8 @@ btr_cur_update_in_place(
 		NOT call it if index is secondary */
 
 		if (!dict_index_is_clust(index)
-		    || row_upd_changes_ord_field_binary(NULL, NULL,
-							index, update)) {
+		    || row_upd_changes_ord_field_binary(index, update, thr,
+							NULL, NULL)) {
 
 			/* Remove possible hash index pointer to this record */
 			btr_search_update_hash_on_delete(cursor);
@@ -2560,6 +2572,7 @@ btr_cur_del_mark_set_clust_rec(
 
 	page_zip = buf_block_get_page_zip(block);
 
+	btr_blob_dbg_set_deleted_flag(rec, index, offsets, val);
 	btr_rec_set_deleted_flag(rec, page_zip, val);
 
 	trx = thr_get_trx(thr);
@@ -3201,9 +3214,54 @@ btr_estimate_n_rows_in_range(
 }
 
 /*******************************************************************//**
+Record the number of non_null key values in a given index for
+each n-column prefix of the index where n < dict_index_get_n_unique(index).
+The estimates are eventually stored in the array:
+index->stat_n_non_null_key_vals. */
+static
+void
+btr_record_not_null_field_in_rec(
+/*=============================*/
+	rec_t*		rec,		/*!< in: physical record */
+	ulint		n_unique,	/*!< in: dict_index_get_n_unique(index),
+					number of columns uniquely determine
+					an index entry */
+	const ulint*	offsets,	/*!< in: rec_get_offsets(rec, index),
+					its size could be for all fields or
+					that of "n_unique" */
+	ib_int64_t*	n_not_null)	/*!< in/out: array to record number of
+					not null rows for n-column prefix */
+{
+	ulint	i;
+
+	ut_ad(rec_offs_n_fields(offsets) >= n_unique);
+
+	if (n_not_null == NULL) {
+		return;
+	}
+
+	for (i = 0; i < n_unique; i++) {
+		ulint	rec_len;
+		byte*	field;
+
+		field = rec_get_nth_field(rec, offsets, i, &rec_len);
+
+		if (rec_len != UNIV_SQL_NULL) {
+			n_not_null[i]++;
+		} else {
+			/* Break if we hit the first NULL value */
+			break;
+		}
+	}
+}
+
+/*******************************************************************//**
 Estimates the number of different key values in a given index, for
 each n-column prefix of the index where n <= dict_index_get_n_unique(index).
-The estimates are stored in the array index->stat_n_diff_key_vals. */
+The estimates are stored in the array index->stat_n_diff_key_vals.
+If innodb_stats_method is "nulls_ignored", we also record the number of
+non-null values for each prefix and store the estimates in
+array index->stat_n_non_null_key_vals. */
 UNIV_INTERN
 void
 btr_estimate_number_of_different_key_vals(
@@ -3217,6 +3275,8 @@ btr_estimate_number_of_different_key_vals(
 	ulint		matched_fields;
 	ulint		matched_bytes;
 	ib_int64_t*	n_diff;
+	ib_int64_t*	n_not_null;
+	ibool		stats_null_not_equal;
 	ullint		n_sample_pages; /* number of pages to sample */
 	ulint		not_empty_flag	= 0;
 	ulint		total_external_size = 0;
@@ -3225,16 +3285,43 @@ btr_estimate_number_of_different_key_vals(
 	ullint		add_on;
 	mtr_t		mtr;
 	mem_heap_t*	heap		= NULL;
-	ulint		offsets_rec_[REC_OFFS_NORMAL_SIZE];
-	ulint		offsets_next_rec_[REC_OFFS_NORMAL_SIZE];
-	ulint*		offsets_rec	= offsets_rec_;
-	ulint*		offsets_next_rec= offsets_next_rec_;
-	rec_offs_init(offsets_rec_);
-	rec_offs_init(offsets_next_rec_);
+	ulint*		offsets_rec	= NULL;
+	ulint*		offsets_next_rec = NULL;
 
 	n_cols = dict_index_get_n_unique(index);
 
-	n_diff = mem_zalloc((n_cols + 1) * sizeof(ib_int64_t));
+	heap = mem_heap_create((sizeof *n_diff + sizeof *n_not_null)
+			       * (n_cols + 1)
+			       + dict_index_get_n_fields(index)
+			       * (sizeof *offsets_rec
+				  + sizeof *offsets_next_rec));
+
+	n_diff = mem_heap_zalloc(heap, (n_cols + 1) * sizeof(ib_int64_t));
+
+	n_not_null = NULL;
+
+	/* Check srv_innodb_stats_method setting, and decide whether we
+	need to record non-null value and also decide if NULL is
+	considered equal (by setting stats_null_not_equal value) */
+	switch (srv_innodb_stats_method) {
+	case SRV_STATS_NULLS_IGNORED:
+		n_not_null = mem_heap_zalloc(heap, (n_cols + 1)
+					     * sizeof *n_not_null);
+		/* fall through */
+
+	case SRV_STATS_NULLS_UNEQUAL:
+		/* for both SRV_STATS_NULLS_IGNORED and SRV_STATS_NULLS_UNEQUAL
+		case, we will treat NULLs as unequal value */
+		stats_null_not_equal = TRUE;
+		break;
+
+	case SRV_STATS_NULLS_EQUAL:
+		stats_null_not_equal = FALSE;
+		break;
+
+	default:
+		ut_error;
+        }
 
 	/* It makes no sense to test more pages than are contained
 	in the index, thus we lower the number if it is too high */
@@ -3251,7 +3338,6 @@ btr_estimate_number_of_different_key_vals(
 	/* We sample some pages in the index to get an estimate */
 
 	for (i = 0; i < n_sample_pages; i++) {
-		rec_t*	supremum;
 		mtr_start(&mtr);
 
 		btr_cur_open_at_rnd_pos(index, BTR_SEARCH_LEAF, &cursor, &mtr);
@@ -3264,18 +3350,25 @@ btr_estimate_number_of_different_key_vals(
 
 		page = btr_cur_get_page(&cursor);
 
-		supremum = page_get_supremum_rec(page);
 		rec = page_rec_get_next(page_get_infimum_rec(page));
 
-		if (rec != supremum) {
+		if (!page_rec_is_supremum(rec)) {
 			not_empty_flag = 1;
 			offsets_rec = rec_get_offsets(rec, index, offsets_rec,
 						      ULINT_UNDEFINED, &heap);
+
+			if (n_not_null) {
+				btr_record_not_null_field_in_rec(
+					rec, n_cols, offsets_rec, n_not_null);
+			}
 		}
 
-		while (rec != supremum) {
+		while (!page_rec_is_supremum(rec)) {
 			rec_t*	next_rec = page_rec_get_next(rec);
-			if (next_rec == supremum) {
+			if (page_rec_is_supremum(next_rec)) {
+				total_external_size +=
+					btr_rec_get_externally_stored_len(
+						rec, offsets_rec);
 				break;
 			}
 
@@ -3283,11 +3376,13 @@ btr_estimate_number_of_different_key_vals(
 			matched_bytes = 0;
 			offsets_next_rec = rec_get_offsets(next_rec, index,
 							   offsets_next_rec,
-							   n_cols, &heap);
+							   ULINT_UNDEFINED,
+							   &heap);
 
 			cmp_rec_rec_with_match(rec, next_rec,
 					       offsets_rec, offsets_next_rec,
-					       index, &matched_fields,
+					       index, stats_null_not_equal,
+					       &matched_fields,
 					       &matched_bytes);
 
 			for (j = matched_fields + 1; j <= n_cols; j++) {
@@ -3297,6 +3392,12 @@ btr_estimate_number_of_different_key_vals(
 				n_diff[j]++;
 			}
 
+			if (n_not_null) {
+				btr_record_not_null_field_in_rec(
+					next_rec, n_cols, offsets_next_rec,
+					n_not_null);
+			}
+
 			total_external_size
 				+= btr_rec_get_externally_stored_len(
 					rec, offsets_rec);
@@ -3331,10 +3432,6 @@ btr_estimate_number_of_different_key_vals(
 			}
 		}
 
-		offsets_rec = rec_get_offsets(rec, index, offsets_rec,
-					      ULINT_UNDEFINED, &heap);
-		total_external_size += btr_rec_get_externally_stored_len(
-			rec, offsets_rec);
 		mtr_commit(&mtr);
 	}
 
@@ -3348,13 +3445,9 @@ btr_estimate_number_of_different_key_vals(
 
 	for (j = 0; j <= n_cols; j++) {
 		index->stat_n_diff_key_vals[j]
-			= ((n_diff[j]
-			    * (ib_int64_t)index->stat_n_leaf_pages
-			    + n_sample_pages - 1
-			    + total_external_size
-			    + not_empty_flag)
-			   / (n_sample_pages
-			      + total_external_size));
+			= BTR_TABLE_STATS_FROM_SAMPLE(
+				n_diff[j], index, n_sample_pages,
+				total_external_size, not_empty_flag); 
 
 		/* If the tree is small, smaller than
 		10 * n_sample_pages + total_external_size, then
@@ -3373,45 +3466,81 @@ btr_estimate_number_of_different_key_vals(
 		}
 
 		index->stat_n_diff_key_vals[j] += add_on;
-	}
 
-	mem_free(n_diff);
-	if (UNIV_LIKELY_NULL(heap)) {
-		mem_heap_free(heap);
+		/* Update the stat_n_non_null_key_vals[] with our
+		sampled result. stat_n_non_null_key_vals[] is created
+		and initialized to zero in dict_index_add_to_cache(),
+		along with stat_n_diff_key_vals[] array */
+		if (n_not_null != NULL && (j < n_cols)) {
+			index->stat_n_non_null_key_vals[j] =
+				 BTR_TABLE_STATS_FROM_SAMPLE(
+					n_not_null[j], index, n_sample_pages,
+					total_external_size, not_empty_flag);
+		}
 	}
+
+	mem_heap_free(heap);
 }
 
 /*================== EXTERNAL STORAGE OF BIG FIELDS ===================*/
 
 /***********************************************************//**
+Gets the offset of the pointer to the externally stored part of a field.
+@return	offset of the pointer to the externally stored part */
+static
+ulint
+btr_rec_get_field_ref_offs(
+/*=======================*/
+	const ulint*	offsets,/*!< in: array returned by rec_get_offsets() */
+	ulint		n)	/*!< in: index of the external field */
+{
+	ulint	field_ref_offs;
+	ulint	local_len;
+
+	ut_a(rec_offs_nth_extern(offsets, n));
+	field_ref_offs = rec_get_nth_field_offs(offsets, n, &local_len);
+	ut_a(local_len != UNIV_SQL_NULL);
+	ut_a(local_len >= BTR_EXTERN_FIELD_REF_SIZE);
+
+	return(field_ref_offs + local_len - BTR_EXTERN_FIELD_REF_SIZE);
+}
+
+/** Gets a pointer to the externally stored part of a field.
+@param rec	record
+@param offsets	rec_get_offsets(rec)
+@param n	index of the externally stored field
+@return pointer to the externally stored part */
+#define btr_rec_get_field_ref(rec, offsets, n)			\
+	((rec) + btr_rec_get_field_ref_offs(offsets, n))
+
+/***********************************************************//**
 Gets the externally stored size of a record, in units of a database page.
 @return	externally stored part, in units of a database page */
 static
 ulint
 btr_rec_get_externally_stored_len(
 /*==============================*/
-	rec_t*		rec,	/*!< in: record */
+	const rec_t*	rec,	/*!< in: record */
 	const ulint*	offsets)/*!< in: array returned by rec_get_offsets() */
 {
 	ulint	n_fields;
-	byte*	data;
-	ulint	local_len;
-	ulint	extern_len;
 	ulint	total_extern_len = 0;
 	ulint	i;
 
 	ut_ad(!rec_offs_comp(offsets) || !rec_get_node_ptr_flag(rec));
+
+	if (!rec_offs_any_extern(offsets)) {
+		return(0);
+	}
+
 	n_fields = rec_offs_n_fields(offsets);
 
 	for (i = 0; i < n_fields; i++) {
 		if (rec_offs_nth_extern(offsets, i)) {
 
-			data = rec_get_nth_field(rec, offsets, i, &local_len);
-
-			local_len -= BTR_EXTERN_FIELD_REF_SIZE;
-
-			extern_len = mach_read_from_4(data + local_len
-						      + BTR_EXTERN_LEN + 4);
+			ulint	extern_len = mach_read_from_4(
+				btr_rec_get_field_ref(rec, offsets, i)
+				+ BTR_EXTERN_LEN + 4);
 
 			total_extern_len += ut_calc_align(extern_len,
 							  UNIV_PAGE_SIZE);
@@ -3441,7 +3570,7 @@ btr_cur_set_ownership_of_extern_field(
 	ulint	byte_val;
 
 	data = rec_get_nth_field(rec, offsets, i, &local_len);
-
+	ut_ad(rec_offs_nth_extern(offsets, i));
 	ut_a(local_len >= BTR_EXTERN_FIELD_REF_SIZE);
 
 	local_len -= BTR_EXTERN_FIELD_REF_SIZE;
@@ -3451,6 +3580,9 @@ btr_cur_set_ownership_of_extern_field(
 	if (val) {
 		byte_val = byte_val & (~BTR_EXTERN_OWNER_FLAG);
 	} else {
+#if defined UNIV_DEBUG || defined UNIV_BLOB_LIGHT_DEBUG
+		ut_a(!(byte_val & BTR_EXTERN_OWNER_FLAG));
+#endif /* UNIV_DEBUG || UNIV_BLOB_LIGHT_DEBUG */
 		byte_val = byte_val | BTR_EXTERN_OWNER_FLAG;
 	}
 
@@ -3464,6 +3596,8 @@ btr_cur_set_ownership_of_extern_field(
 	} else {
 		mach_write_to_1(data + local_len + BTR_EXTERN_LEN, byte_val);
 	}
+
+	btr_blob_dbg_owner(rec, index, offsets, i, val);
 }
 
 /*******************************************************************//**
@@ -3667,13 +3801,12 @@ btr_blob_free(
 	    && buf_block_get_space(block) == space
 	    && buf_block_get_page_no(block) == page_no) {
 
-		if (buf_LRU_free_block(&block->page, all, NULL)
-		    != BUF_LRU_FREED
+		if (buf_LRU_free_block(&block->page, all) != BUF_LRU_FREED
 		    && all && block->page.zip.data) {
 			/* Attempt to deallocate the uncompressed page
 			if the whole block cannot be deallocted. */
 
-			buf_LRU_free_block(&block->page, FALSE, NULL);
+			buf_LRU_free_block(&block->page, FALSE);
 		}
 	}
 
@@ -3689,8 +3822,8 @@ file segment of the index tree.
 @return	DB_SUCCESS or DB_OUT_OF_FILE_SPACE */
 UNIV_INTERN
 ulint
-btr_store_big_rec_extern_fields(
-/*============================*/
+btr_store_big_rec_extern_fields_func(
+/*=================================*/
 	dict_index_t*	index,		/*!< in: index of rec; the index tree
 					MUST be X-latched */
 	buf_block_t*	rec_block,	/*!< in/out: block containing rec */
@@ -3699,11 +3832,17 @@ btr_store_big_rec_extern_fields(
 					the "external storage" flags in offsets
 					will not correspond to rec when
 					this function returns */
-	big_rec_t*	big_rec_vec,	/*!< in: vector containing fields
+#ifdef UNIV_DEBUG
+	mtr_t*		local_mtr,	/*!< in: mtr containing the
+					latch to rec and to the tree */
+#endif /* UNIV_DEBUG */
+#if defined UNIV_DEBUG || defined UNIV_BLOB_LIGHT_DEBUG
+	ibool		update_in_place,/*! in: TRUE if the record is updated
+					in place (not delete+insert) */
+#endif /* UNIV_DEBUG || UNIV_BLOB_LIGHT_DEBUG */
+	const big_rec_t*big_rec_vec)	/*!< in: vector containing fields
 					to be stored externally */
-	mtr_t*		local_mtr __attribute__((unused))) /*!< in: mtr
-					containing the latch to rec and to the
-					tree */
+
 {
 	ulint	rec_page_no;
 	byte*	field_ref;
@@ -3721,6 +3860,7 @@ btr_store_big_rec_extern_fields(
 	z_stream c_stream;
 
 	ut_ad(rec_offs_validate(rec, index, offsets));
+	ut_ad(rec_offs_any_extern(offsets));
 	ut_ad(mtr_memo_contains(local_mtr, dict_index_get_lock(index),
 				MTR_MEMO_X_LOCK));
 	ut_ad(mtr_memo_contains(local_mtr, rec_block, MTR_MEMO_PAGE_X_FIX));
@@ -3752,21 +3892,37 @@ btr_store_big_rec_extern_fields(
 		ut_a(err == Z_OK);
 	}
 
+#if defined UNIV_DEBUG || defined UNIV_BLOB_LIGHT_DEBUG
+	/* All pointers to externally stored columns in the record
+	must either be zero or they must be pointers to inherited
+	columns, owned by this record or an earlier record version. */
+	for (i = 0; i < rec_offs_n_fields(offsets); i++) {
+		if (!rec_offs_nth_extern(offsets, i)) {
+			continue;
+		}
+		field_ref = btr_rec_get_field_ref(rec, offsets, i);
+
+		ut_a(!(field_ref[BTR_EXTERN_LEN] & BTR_EXTERN_OWNER_FLAG));
+		/* Either this must be an update in place,
+		or the BLOB must be inherited, or the BLOB pointer
+		must be zero (will be written in this function). */
+		ut_a(update_in_place
+		     || (field_ref[BTR_EXTERN_LEN] & BTR_EXTERN_INHERITED_FLAG)
+		     || !memcmp(field_ref, field_ref_zero,
+				BTR_EXTERN_FIELD_REF_SIZE));
+	}
+#endif /* UNIV_DEBUG || UNIV_BLOB_LIGHT_DEBUG */
 	/* We have to create a file segment to the tablespace
 	for each field and put the pointer to the field in rec */
 
 	for (i = 0; i < big_rec_vec->n_fields; i++) {
-		ut_ad(rec_offs_nth_extern(offsets,
-					  big_rec_vec->fields[i].field_no));
-		{
-			ulint	local_len;
-			field_ref = rec_get_nth_field(
-				rec, offsets, big_rec_vec->fields[i].field_no,
-				&local_len);
-			ut_a(local_len >= BTR_EXTERN_FIELD_REF_SIZE);
-			local_len -= BTR_EXTERN_FIELD_REF_SIZE;
-			field_ref += local_len;
-		}
+		field_ref = btr_rec_get_field_ref(
+			rec, offsets, big_rec_vec->fields[i].field_no);
+#if defined UNIV_DEBUG || defined UNIV_BLOB_LIGHT_DEBUG
+		/* A zero BLOB pointer should have been initially inserted. */
+		ut_a(!memcmp(field_ref, field_ref_zero,
+			     BTR_EXTERN_FIELD_REF_SIZE));
+#endif /* UNIV_DEBUG || UNIV_BLOB_LIGHT_DEBUG */
 		extern_len = big_rec_vec->fields[i].len;
 		UNIV_MEM_ASSERT_RW(big_rec_vec->fields[i].data,
 				   extern_len);
@@ -3941,6 +4097,11 @@ btr_store_big_rec_extern_fields(
 				}
 
 				if (prev_page_no == FIL_NULL) {
+					btr_blob_dbg_add_blob(
+						rec, big_rec_vec->fields[i]
+						.field_no, page_no, index,
+						"store");
+
 					mach_write_to_4(field_ref
 							+ BTR_EXTERN_SPACE_ID,
 							space_id);
@@ -4016,6 +4177,11 @@ next_zip_page:
 						 MLOG_4BYTES, &mtr);
 
 				if (prev_page_no == FIL_NULL) {
+					btr_blob_dbg_add_blob(
+						rec, big_rec_vec->fields[i]
+						.field_no, page_no, index,
+						"store");
+
 					mlog_write_ulint(field_ref
 							 + BTR_EXTERN_SPACE_ID,
 							 space_id,
@@ -4048,6 +4214,23 @@ next_zip_page:
 		mem_heap_free(heap);
 	}
 
+#if defined UNIV_DEBUG || defined UNIV_BLOB_LIGHT_DEBUG
+	/* All pointers to externally stored columns in the record
+	must be valid. */
+	for (i = 0; i < rec_offs_n_fields(offsets); i++) {
+		if (!rec_offs_nth_extern(offsets, i)) {
+			continue;
+		}
+
+		field_ref = btr_rec_get_field_ref(rec, offsets, i);
+
+		/* The pointer must not be zero. */
+		ut_a(0 != memcmp(field_ref, field_ref_zero,
+				 BTR_EXTERN_FIELD_REF_SIZE));
+		/* The column must not be disowned by this record. */
+		ut_a(!(field_ref[BTR_EXTERN_LEN] & BTR_EXTERN_OWNER_FLAG));
+	}
+#endif /* UNIV_DEBUG || UNIV_BLOB_LIGHT_DEBUG */
 	return(DB_SUCCESS);
 }
 
@@ -4070,6 +4253,7 @@ btr_check_blob_fil_page_type(
 	if (UNIV_UNLIKELY(type != FIL_PAGE_TYPE_BLOB)) {
 		ulint	flags = fil_space_get_flags(space_id);
 
+#ifndef UNIV_DEBUG /* Improve debug test coverage */
 		if (UNIV_LIKELY
 		    ((flags & DICT_TF_FORMAT_MASK) == DICT_TF_FORMAT_51)) {
 			/* Old versions of InnoDB did not initialize
@@ -4078,6 +4262,7 @@ btr_check_blob_fil_page_type(
 			a BLOB page that is in Antelope format.*/
 			return;
 		}
+#endif /* !UNIV_DEBUG */
 
 		ut_print_timestamp(stderr);
 		fprintf(stderr,
@@ -4127,23 +4312,13 @@ btr_free_externally_stored_field(
 	ulint		page_no;
 	ulint		next_page_no;
 	mtr_t		mtr;
-#ifdef UNIV_DEBUG
+
 	ut_ad(mtr_memo_contains(local_mtr, dict_index_get_lock(index),
 				MTR_MEMO_X_LOCK));
 	ut_ad(mtr_memo_contains_page(local_mtr, field_ref,
 				     MTR_MEMO_PAGE_X_FIX));
 	ut_ad(!rec || rec_offs_validate(rec, index, offsets));
-
-	if (rec) {
-		ulint	local_len;
-		const byte*	f = rec_get_nth_field(rec, offsets,
-						      i, &local_len);
-		ut_a(local_len >= BTR_EXTERN_FIELD_REF_SIZE);
-		local_len -= BTR_EXTERN_FIELD_REF_SIZE;
-		f += local_len;
-		ut_ad(f == field_ref);
-	}
-#endif /* UNIV_DEBUG */
+	ut_ad(!rec || field_ref == btr_rec_get_field_ref(rec, offsets, i));
 
 	if (UNIV_UNLIKELY(!memcmp(field_ref, field_ref_zero,
 				  BTR_EXTERN_FIELD_REF_SIZE))) {
@@ -4175,6 +4350,37 @@ btr_free_externally_stored_field(
 		rec_zip_size = 0;
 	}
 
+#ifdef UNIV_BLOB_DEBUG
+	if (!(field_ref[BTR_EXTERN_LEN] & BTR_EXTERN_OWNER_FLAG)
+	    && !((field_ref[BTR_EXTERN_LEN] & BTR_EXTERN_INHERITED_FLAG)
+		 && (rb_ctx == RB_NORMAL || rb_ctx == RB_RECOVERY))) {
+		/* This off-page column will be freed.
+		Check that no references remain. */
+
+		btr_blob_dbg_t	b;
+
+		b.blob_page_no = mach_read_from_4(
+			field_ref + BTR_EXTERN_PAGE_NO);
+
+		if (rec) {
+			/* Remove the reference from the record to the
+			BLOB. If the BLOB were not freed, the
+			reference would be removed when the record is
+			removed. Freeing the BLOB will overwrite the
+			BTR_EXTERN_PAGE_NO in the field_ref of the
+			record with FIL_NULL, which would make the
+			btr_blob_dbg information inconsistent with the
+			record. */
+			b.ref_page_no = page_get_page_no(page_align(rec));
+			b.ref_heap_no = page_rec_get_heap_no(rec);
+			b.ref_field_no = i;
+			btr_blob_dbg_rbt_delete(index, &b, "free");
+		}
+
+		btr_blob_dbg_assert_empty(index, b.blob_page_no);
+	}
+#endif /* UNIV_BLOB_DEBUG */
+
 	for (;;) {
 #ifdef UNIV_SYNC_DEBUG
 		buf_block_t*	rec_block;
@@ -4308,13 +4514,8 @@ btr_rec_free_externally_stored_fields(
 
 	for (i = 0; i < n_fields; i++) {
 		if (rec_offs_nth_extern(offsets, i)) {
-			ulint	len;
-			byte*	data
-				= rec_get_nth_field(rec, offsets, i, &len);
-			ut_a(len >= BTR_EXTERN_FIELD_REF_SIZE);
-
 			btr_free_externally_stored_field(
-				index, data + len - BTR_EXTERN_FIELD_REF_SIZE,
+				index, btr_rec_get_field_ref(rec, offsets, i),
 				rec, offsets, page_zip, i, rb_ctx, mtr);
 		}
 	}
@@ -4426,27 +4627,45 @@ btr_copy_blob_prefix(
 
 /*******************************************************************//**
 Copies the prefix of a compressed BLOB.  The clustered index record
-that points to this BLOB must be protected by a lock or a page latch. */
+that points to this BLOB must be protected by a lock or a page latch.
+@return	number of bytes written to buf */
 static
-void
+ulint
 btr_copy_zblob_prefix(
 /*==================*/
-	z_stream*	d_stream,/*!< in/out: the decompressing stream */
+	byte*		buf,	/*!< out: the externally stored part of
+				the field, or a prefix of it */
+	ulint		len,	/*!< in: length of buf, in bytes */
 	ulint		zip_size,/*!< in: compressed BLOB page size */
 	ulint		space_id,/*!< in: space id of the BLOB pages */
 	ulint		page_no,/*!< in: page number of the first BLOB page */
 	ulint		offset)	/*!< in: offset on the first BLOB page */
 {
-	ulint	page_type = FIL_PAGE_TYPE_ZBLOB;
+	ulint		page_type = FIL_PAGE_TYPE_ZBLOB;
+	mem_heap_t*	heap;
+	int		err;
+	z_stream	d_stream;
+
+	d_stream.next_out = buf;
+	d_stream.avail_out = len;
+	d_stream.next_in = Z_NULL;
+	d_stream.avail_in = 0;
+
+	/* Zlib inflate needs 32 kilobytes for the default
+	window size, plus a few kilobytes for small objects. */
+	heap = mem_heap_create(40000);
+	page_zip_set_alloc(&d_stream, heap);
 
 	ut_ad(ut_is_2pow(zip_size));
 	ut_ad(zip_size >= PAGE_ZIP_MIN_SIZE);
 	ut_ad(zip_size <= UNIV_PAGE_SIZE);
 	ut_ad(space_id);
 
+	err = inflateInit(&d_stream);
+	ut_a(err == Z_OK);
+
 	for (;;) {
 		buf_page_t*	bpage;
-		int		err;
 		ulint		next_page_no;
 
 		/* There is no latch on bpage directly.  Instead,
@@ -4462,7 +4681,7 @@ btr_copy_zblob_prefix(
 				" compressed BLOB"
 				" page %lu space %lu\n",
 				(ulong) page_no, (ulong) space_id);
-			return;
+			goto func_exit;
 		}
 
 		if (UNIV_UNLIKELY
@@ -4488,13 +4707,13 @@ btr_copy_zblob_prefix(
 			offset += 4;
 		}
 
-		d_stream->next_in = bpage->zip.data + offset;
-		d_stream->avail_in = zip_size - offset;
+		d_stream.next_in = bpage->zip.data + offset;
+		d_stream.avail_in = zip_size - offset;
 
-		err = inflate(d_stream, Z_NO_FLUSH);
+		err = inflate(&d_stream, Z_NO_FLUSH);
 		switch (err) {
 		case Z_OK:
-			if (!d_stream->avail_out) {
+			if (!d_stream.avail_out) {
 				goto end_of_blob;
 			}
 			break;
@@ -4511,13 +4730,13 @@ inflate_error:
 				" compressed BLOB"
 				" page %lu space %lu returned %d (%s)\n",
 				(ulong) page_no, (ulong) space_id,
-				err, d_stream->msg);
+				err, d_stream.msg);
 		case Z_BUF_ERROR:
 			goto end_of_blob;
 		}
 
 		if (next_page_no == FIL_NULL) {
-			if (!d_stream->avail_in) {
+			if (!d_stream.avail_in) {
 				ut_print_timestamp(stderr);
 				fprintf(stderr,
 					"  InnoDB: unexpected end of"
@@ -4526,7 +4745,7 @@ inflate_error:
 					(ulong) page_no,
 					(ulong) space_id);
 			} else {
-				err = inflate(d_stream, Z_FINISH);
+				err = inflate(&d_stream, Z_FINISH);
 				switch (err) {
 				case Z_STREAM_END:
 				case Z_BUF_ERROR:
@@ -4538,7 +4757,7 @@ inflate_error:
 
 end_of_blob:
 			buf_page_release_zip(bpage);
-			return;
+			goto func_exit;
 		}
 
 		buf_page_release_zip(bpage);
@@ -4550,6 +4769,12 @@ end_of_blob:
 		offset = FIL_PAGE_NEXT;
 		page_type = FIL_PAGE_TYPE_ZBLOB2;
 	}
+
+func_exit:
+	inflateEnd(&d_stream);
+	mem_heap_free(heap);
+	UNIV_MEM_ASSERT_RW(buf, d_stream.total_out);
+	return(d_stream.total_out);
 }
 
 /*******************************************************************//**
@@ -4575,28 +4800,8 @@ btr_copy_externally_stored_field_prefix_low(
 	}
 
 	if (UNIV_UNLIKELY(zip_size)) {
-		int		err;
-		z_stream	d_stream;
-		mem_heap_t*	heap;
-
-		/* Zlib inflate needs 32 kilobytes for the default
-		window size, plus a few kilobytes for small objects. */
-		heap = mem_heap_create(40000);
-		page_zip_set_alloc(&d_stream, heap);
-
-		err = inflateInit(&d_stream);
-		ut_a(err == Z_OK);
-
-		d_stream.next_out = buf;
-		d_stream.avail_out = len;
-		d_stream.avail_in = 0;
-
-		btr_copy_zblob_prefix(&d_stream, zip_size,
-				      space_id, page_no, offset);
-		inflateEnd(&d_stream);
-		mem_heap_free(heap);
-		UNIV_MEM_ASSERT_RW(buf, d_stream.total_out);
-		return(d_stream.total_out);
+		return(btr_copy_zblob_prefix(buf, len, zip_size,
+					     space_id, page_no, offset));
 	} else {
 		return(btr_copy_blob_prefix(buf, len, space_id,
 					    page_no, offset));
diff --git a/storage/innodb_plugin/btr/btr0sea.c b/storage/innodb_plugin/btr/btr0sea.c
index 035fdbb61d2..cd0eadbb1b8 100644
--- a/storage/innodb_plugin/btr/btr0sea.c
+++ b/storage/innodb_plugin/btr/btr0sea.c
@@ -141,7 +141,7 @@ btr_search_check_free_space_in_heap(void)
 	be enough free space in the hash table. */
 
 	if (heap->free_block == NULL) {
-		buf_block_t*	block = buf_block_alloc(0);
+		buf_block_t*	block = buf_block_alloc();
 
 		rw_lock_x_lock(&btr_search_latch);
 
@@ -1201,8 +1201,8 @@ btr_search_drop_page_hash_when_freed(
 	having to fear a deadlock. */
 
 	block = buf_page_get_gen(space, zip_size, page_no, RW_S_LATCH, NULL,
-				BUF_GET_IF_IN_POOL, __FILE__, __LINE__,
-				&mtr);
+				 BUF_PEEK_IF_IN_POOL, __FILE__, __LINE__,
+				 &mtr);
 	/* Because the buffer pool mutex was released by
 	buf_page_peek_if_search_hashed(), it is possible that the
 	block was removed from the buffer pool by another thread
diff --git a/storage/innodb_plugin/buf/buf0buddy.c b/storage/innodb_plugin/buf/buf0buddy.c
index ee5a569c3ff..63c99571510 100644
--- a/storage/innodb_plugin/buf/buf0buddy.c
+++ b/storage/innodb_plugin/buf/buf0buddy.c
@@ -327,7 +327,7 @@ buf_buddy_alloc_low(
 
 	/* Try replacing an uncompressed page in the buffer pool. */
 	buf_pool_mutex_exit();
-	block = buf_LRU_get_free_block(0);
+	block = buf_LRU_get_free_block();
 	*lru = TRUE;
 	buf_pool_mutex_enter();
 
diff --git a/storage/innodb_plugin/buf/buf0buf.c b/storage/innodb_plugin/buf/buf0buf.c
index dac416f9472..14ec7b75911 100644
--- a/storage/innodb_plugin/buf/buf0buf.c
+++ b/storage/innodb_plugin/buf/buf0buf.c
@@ -657,9 +657,9 @@ buf_block_init(
 
 	block->modify_clock = 0;
 
-#ifdef UNIV_DEBUG_FILE_ACCESSES
+#if defined UNIV_DEBUG_FILE_ACCESSES || defined UNIV_DEBUG
 	block->page.file_page_was_freed = FALSE;
-#endif /* UNIV_DEBUG_FILE_ACCESSES */
+#endif /* UNIV_DEBUG_FILE_ACCESSES || UNIV_DEBUG */
 
 	block->check_index_page_at_flush = FALSE;
 	block->index = NULL;
@@ -1283,7 +1283,7 @@ shrink_again:
 
 				buf_LRU_make_block_old(&block->page);
 				dirty++;
-			} else if (buf_LRU_free_block(&block->page, TRUE, NULL)
+			} else if (buf_LRU_free_block(&block->page, TRUE)
 				   != BUF_LRU_FREED) {
 				nonfree++;
 			}
@@ -1600,7 +1600,7 @@ buf_page_peek_if_search_hashed(
 	return(is_hashed);
 }
 
-#ifdef UNIV_DEBUG_FILE_ACCESSES
+#if defined UNIV_DEBUG_FILE_ACCESSES || defined UNIV_DEBUG
 /********************************************************************//**
 Sets file_page_was_freed TRUE if the page is found in the buffer pool.
 This function should be called when we free a file page and want the
@@ -1621,6 +1621,8 @@ buf_page_set_file_page_was_freed(
 	bpage = buf_page_hash_get(space, offset);
 
 	if (bpage) {
+		/* bpage->file_page_was_freed can already hold
+		when this code is invoked from dict_drop_index_tree() */
 		bpage->file_page_was_freed = TRUE;
 	}
 
@@ -1656,7 +1658,7 @@ buf_page_reset_file_page_was_freed(
 
 	return(bpage);
 }
-#endif /* UNIV_DEBUG_FILE_ACCESSES */
+#endif /* UNIV_DEBUG_FILE_ACCESSES || UNIV_DEBUG */
 
 /********************************************************************//**
 Get read access to a compressed page (usually of type
@@ -1729,8 +1731,7 @@ err_exit:
 		mutex_enter(block_mutex);
 
 		/* Discard the uncompressed page frame if possible. */
-		if (buf_LRU_free_block(bpage, FALSE, NULL)
-		    == BUF_LRU_FREED) {
+		if (buf_LRU_free_block(bpage, FALSE) == BUF_LRU_FREED) {
 
 			mutex_exit(block_mutex);
 			goto lookup;
@@ -1754,7 +1755,7 @@ got_block:
 
 	buf_page_set_accessed_make_young(bpage, access_time);
 
-#ifdef UNIV_DEBUG_FILE_ACCESSES
+#if defined UNIV_DEBUG_FILE_ACCESSES || defined UNIV_DEBUG
 	ut_a(!bpage->file_page_was_freed);
 #endif
 
@@ -1892,16 +1893,19 @@ buf_block_align(
 	/* TODO: protect buf_pool->chunks with a mutex (it will
 	currently remain constant after buf_pool_init()) */
 	for (chunk = buf_pool->chunks, i = buf_pool->n_chunks; i--; chunk++) {
-		lint	offs = ptr - chunk->blocks->frame;
+		ulint	offs;
 
-		if (UNIV_UNLIKELY(offs < 0)) {
+		if (UNIV_UNLIKELY(ptr < chunk->blocks->frame)) {
 
 			continue;
 		}
+		/* else */
+
+		offs = ptr - chunk->blocks->frame;
 
 		offs >>= UNIV_PAGE_SIZE_SHIFT;
 
-		if (UNIV_LIKELY((ulint) offs < chunk->size)) {
+		if (UNIV_LIKELY(offs < chunk->size)) {
 			buf_block_t*	block = &chunk->blocks[offs];
 
 			/* The function buf_chunk_init() invokes
@@ -2027,7 +2031,7 @@ buf_page_get_gen(
 	ulint		rw_latch,/*!< in: RW_S_LATCH, RW_X_LATCH, RW_NO_LATCH */
 	buf_block_t*	guess,	/*!< in: guessed block or NULL */
 	ulint		mode,	/*!< in: BUF_GET, BUF_GET_IF_IN_POOL,
-				BUF_GET_NO_LATCH */
+				BUF_PEEK_IF_IN_POOL, BUF_GET_NO_LATCH */
 	const char*	file,	/*!< in: file name */
 	ulint		line,	/*!< in: line where called */
 	mtr_t*		mtr)	/*!< in: mini-transaction */
@@ -2043,9 +2047,19 @@ buf_page_get_gen(
 	ut_ad((rw_latch == RW_S_LATCH)
 	      || (rw_latch == RW_X_LATCH)
 	      || (rw_latch == RW_NO_LATCH));
-	ut_ad((mode != BUF_GET_NO_LATCH) || (rw_latch == RW_NO_LATCH));
-	ut_ad((mode == BUF_GET) || (mode == BUF_GET_IF_IN_POOL)
-	      || (mode == BUF_GET_NO_LATCH));
+#ifdef UNIV_DEBUG
+	switch (mode) {
+	case BUF_GET_NO_LATCH:
+		ut_ad(rw_latch == RW_NO_LATCH);
+		break;
+	case BUF_GET:
+	case BUF_GET_IF_IN_POOL:
+	case BUF_PEEK_IF_IN_POOL:
+		break;
+	default:
+		ut_error;
+	}
+#endif /* UNIV_DEBUG */
 	ut_ad(zip_size == fil_space_get_zip_size(space));
 	ut_ad(ut_is_2pow(zip_size));
 #ifndef UNIV_LOG_DEBUG
@@ -2087,7 +2101,8 @@ loop2:
 
 		buf_pool_mutex_exit();
 
-		if (mode == BUF_GET_IF_IN_POOL) {
+		if (mode == BUF_GET_IF_IN_POOL
+		    || mode == BUF_PEEK_IF_IN_POOL) {
 
 			return(NULL);
 		}
@@ -2126,7 +2141,8 @@ loop2:
 
 	must_read = buf_block_get_io_fix(block) == BUF_IO_READ;
 
-	if (must_read && mode == BUF_GET_IF_IN_POOL) {
+	if (must_read && (mode == BUF_GET_IF_IN_POOL
+			  || mode == BUF_PEEK_IF_IN_POOL)) {
 		/* The page is only being read to buffer */
 		buf_pool_mutex_exit();
 
@@ -2165,7 +2181,7 @@ wait_until_unfixed:
 		buf_pool_mutex_exit();
 		mutex_exit(&buf_pool_zip_mutex);
 
-		block = buf_LRU_get_free_block(0);
+		block = buf_LRU_get_free_block();
 		ut_a(block);
 
 		buf_pool_mutex_enter();
@@ -2244,6 +2260,7 @@ wait_until_unfixed:
 		mutex_exit(&buf_pool_zip_mutex);
 		buf_pool->n_pend_unzip++;
 
+		bpage->state = BUF_BLOCK_ZIP_FREE;
 		buf_buddy_free(bpage, sizeof *bpage);
 
 		buf_pool_mutex_exit();
@@ -2291,8 +2308,7 @@ wait_until_unfixed:
 		/* Try to evict the block from the buffer pool, to use the
 		insert buffer as much as possible. */
 
-		if (buf_LRU_free_block(&block->page, TRUE, NULL)
-		    == BUF_LRU_FREED) {
+		if (buf_LRU_free_block(&block->page, TRUE) == BUF_LRU_FREED) {
 			buf_pool_mutex_exit();
 			mutex_exit(&block->mutex);
 			fprintf(stderr,
@@ -2321,9 +2337,11 @@ wait_until_unfixed:
 
 	buf_pool_mutex_exit();
 
-	buf_page_set_accessed_make_young(&block->page, access_time);
+	if (UNIV_LIKELY(mode != BUF_PEEK_IF_IN_POOL)) {
+		buf_page_set_accessed_make_young(&block->page, access_time);
+	}
 
-#ifdef UNIV_DEBUG_FILE_ACCESSES
+#if defined UNIV_DEBUG_FILE_ACCESSES || defined UNIV_DEBUG
 	ut_a(!block->page.file_page_was_freed);
 #endif
 
@@ -2374,7 +2392,7 @@ wait_until_unfixed:
 
 	mtr_memo_push(mtr, block, fix_type);
 
-	if (!access_time) {
+	if (UNIV_LIKELY(mode != BUF_PEEK_IF_IN_POOL) && !access_time) {
 		/* In the case of a first access, try to apply linear
 		read-ahead */
 
@@ -2481,7 +2499,7 @@ buf_page_optimistic_get(
 	ut_a(buf_block_get_state(block) == BUF_BLOCK_FILE_PAGE);
 #endif /* UNIV_DEBUG || UNIV_BUF_DEBUG */
 
-#ifdef UNIV_DEBUG_FILE_ACCESSES
+#if defined UNIV_DEBUG_FILE_ACCESSES || defined UNIV_DEBUG
 	ut_a(block->page.file_page_was_freed == FALSE);
 #endif
 	if (UNIV_UNLIKELY(!access_time)) {
@@ -2589,7 +2607,7 @@ buf_page_get_known_nowait(
 	ut_a(block->page.buf_fix_count > 0);
 	ut_a(buf_block_get_state(block) == BUF_BLOCK_FILE_PAGE);
 #endif /* UNIV_DEBUG || UNIV_BUF_DEBUG */
-#ifdef UNIV_DEBUG_FILE_ACCESSES
+#if defined UNIV_DEBUG_FILE_ACCESSES || defined UNIV_DEBUG
 	ut_a(block->page.file_page_was_freed == FALSE);
 #endif
 
@@ -2672,9 +2690,9 @@ buf_page_try_get_func(
 	ut_a(block->page.buf_fix_count > 0);
 	ut_a(buf_block_get_state(block) == BUF_BLOCK_FILE_PAGE);
 #endif /* UNIV_DEBUG || UNIV_BUF_DEBUG */
-#ifdef UNIV_DEBUG_FILE_ACCESSES
+#if defined UNIV_DEBUG_FILE_ACCESSES || defined UNIV_DEBUG
 	ut_a(block->page.file_page_was_freed == FALSE);
-#endif /* UNIV_DEBUG_FILE_ACCESSES */
+#endif /* UNIV_DEBUG_FILE_ACCESSES || UNIV_DEBUG */
 	buf_block_dbg_add_level(block, SYNC_NO_ORDER_CHECK);
 
 	buf_pool->stat.n_page_gets++;
@@ -2703,9 +2721,9 @@ buf_page_init_low(
 	bpage->newest_modification = 0;
 	bpage->oldest_modification = 0;
 	HASH_INVALIDATE(bpage, hash);
-#ifdef UNIV_DEBUG_FILE_ACCESSES
+#if defined UNIV_DEBUG_FILE_ACCESSES || defined UNIV_DEBUG
 	bpage->file_page_was_freed = FALSE;
-#endif /* UNIV_DEBUG_FILE_ACCESSES */
+#endif /* UNIV_DEBUG_FILE_ACCESSES || UNIV_DEBUG */
 }
 
 /********************************************************************//**
@@ -2829,7 +2847,7 @@ buf_page_init_for_read(
 	    && UNIV_LIKELY(!recv_recovery_is_on())) {
 		block = NULL;
 	} else {
-		block = buf_LRU_get_free_block(0);
+		block = buf_LRU_get_free_block();
 		ut_ad(block);
 	}
 
@@ -2923,6 +2941,7 @@ err_exit:
 		    && UNIV_LIKELY_NULL(buf_page_hash_get(space, offset))) {
 
 			/* The block was added by some other thread. */
+			bpage->state = BUF_BLOCK_ZIP_FREE;
 			buf_buddy_free(bpage, sizeof *bpage);
 			buf_buddy_free(data, zip_size);
 
@@ -3001,7 +3020,7 @@ buf_page_create(
 	ut_ad(mtr->state == MTR_ACTIVE);
 	ut_ad(space || !zip_size);
 
-	free_block = buf_LRU_get_free_block(0);
+	free_block = buf_LRU_get_free_block();
 
 	buf_pool_mutex_enter();
 
@@ -3011,9 +3030,9 @@ buf_page_create(
 #ifdef UNIV_IBUF_COUNT_DEBUG
 		ut_a(ibuf_count_get(space, offset) == 0);
 #endif
-#ifdef UNIV_DEBUG_FILE_ACCESSES
+#if defined UNIV_DEBUG_FILE_ACCESSES || defined UNIV_DEBUG
 		block->page.file_page_was_freed = FALSE;
-#endif /* UNIV_DEBUG_FILE_ACCESSES */
+#endif /* UNIV_DEBUG_FILE_ACCESSES || UNIV_DEBUG */
 
 		/* Page can be found in buf_pool */
 		buf_pool_mutex_exit();
diff --git a/storage/innodb_plugin/buf/buf0lru.c b/storage/innodb_plugin/buf/buf0lru.c
index e4cf218bf2e..a69b2658c51 100644
--- a/storage/innodb_plugin/buf/buf0lru.c
+++ b/storage/innodb_plugin/buf/buf0lru.c
@@ -246,71 +246,75 @@ buf_LRU_drop_page_hash_for_tablespace(
 	page_arr = ut_malloc(sizeof(ulint)
 			     * BUF_LRU_DROP_SEARCH_HASH_SIZE);
 	buf_pool_mutex_enter();
+	num_entries = 0;
 
 scan_again:
-	num_entries = 0;
 	bpage = UT_LIST_GET_LAST(buf_pool->LRU);
 
 	while (bpage != NULL) {
-		mutex_t*	block_mutex = buf_page_get_mutex(bpage);
 		buf_page_t*	prev_bpage;
+		ibool		is_fixed;
 
-		mutex_enter(block_mutex);
 		prev_bpage = UT_LIST_GET_PREV(LRU, bpage);
 
 		ut_a(buf_page_in_file(bpage));
 
 		if (buf_page_get_state(bpage) != BUF_BLOCK_FILE_PAGE
 		    || bpage->space != id
-		    || bpage->buf_fix_count > 0
 		    || bpage->io_fix != BUF_IO_NONE) {
-			/* We leave the fixed pages as is in this scan.
-			To be dealt with later in the final scan. */
-			mutex_exit(block_mutex);
-			goto next_page;
+			/* Compressed pages are never hashed.
+			Skip blocks of other tablespaces.
+			Skip I/O-fixed blocks (to be dealt with later). */
+next_page:
+			bpage = prev_bpage;
+			continue;
 		}
 
-		if (((buf_block_t*) bpage)->is_hashed) {
+		mutex_enter(&((buf_block_t*) bpage)->mutex);
+		is_fixed = bpage->buf_fix_count > 0
+			|| !((buf_block_t*) bpage)->is_hashed;
+		mutex_exit(&((buf_block_t*) bpage)->mutex);
 
-			/* Store the offset(i.e.: page_no) in the array
-			so that we can drop hash index in a batch
-			later. */
-			page_arr[num_entries] = bpage->offset;
-			mutex_exit(block_mutex);
-			ut_a(num_entries < BUF_LRU_DROP_SEARCH_HASH_SIZE);
-			++num_entries;
+		if (is_fixed) {
+			goto next_page;
+		}
 
-			if (num_entries < BUF_LRU_DROP_SEARCH_HASH_SIZE) {
-				goto next_page;
-			}
-			/* Array full. We release the buf_pool_mutex to
-			obey the latching order. */
-			buf_pool_mutex_exit();
-
-			buf_LRU_drop_page_hash_batch(id, zip_size, page_arr,
-						     num_entries);
-			num_entries = 0;
-			buf_pool_mutex_enter();
-		} else {
-			mutex_exit(block_mutex);
+		/* Store the page number so that we can drop the hash
+		index in a batch later. */
+		page_arr[num_entries] = bpage->offset;
+		ut_a(num_entries < BUF_LRU_DROP_SEARCH_HASH_SIZE);
+		++num_entries;
+
+		if (num_entries < BUF_LRU_DROP_SEARCH_HASH_SIZE) {
+			goto next_page;
 		}
 
-next_page:
-		/* Note that we may have released the buf_pool mutex
-		above after reading the prev_bpage during processing
-		of a page_hash_batch (i.e.: when the array was full).
-		This means that prev_bpage can change in LRU list.
-		This is OK because this function is a 'best effort'
-		to drop as many search hash entries as possible and
-		it does not guarantee that ALL such entries will be
-		dropped. */
-		bpage = prev_bpage;
+		/* Array full. We release the buf_pool_mutex to
+		obey the latching order. */
+		buf_pool_mutex_exit();
+		buf_LRU_drop_page_hash_batch(id, zip_size, page_arr,
+					     num_entries);
+		buf_pool_mutex_enter();
+		num_entries = 0;
+
+		/* Note that we released the buf_pool mutex above
+		after reading the prev_bpage during processing of a
+		page_hash_batch (i.e.: when the array was full).
+		Because prev_bpage could belong to a compressed-only
+		block, it may have been relocated, and thus the
+		pointer cannot be trusted. Because bpage is of type
+		buf_block_t, it is safe to dereference.
+
+		bpage can change in the LRU list. This is OK because
+		this function is a 'best effort' to drop as many
+		search hash entries as possible and it does not
+		guarantee that ALL such entries will be dropped. */
 
 		/* If, however, bpage has been removed from LRU list
 		to the free list then we should restart the scan.
 		bpage->state is protected by buf_pool mutex. */
-		if (bpage && !buf_page_in_file(bpage)) {
-			ut_a(num_entries == 0);
+		if (bpage
+		    && buf_page_get_state(bpage) != BUF_BLOCK_FILE_PAGE) {
 			goto scan_again;
 		}
 	}
@@ -575,7 +579,7 @@ buf_LRU_free_from_unzip_LRU_list(
 		ut_ad(block->page.in_LRU_list);
 
 		mutex_enter(&block->mutex);
-		freed = buf_LRU_free_block(&block->page, FALSE, NULL);
+		freed = buf_LRU_free_block(&block->page, FALSE);
 		mutex_exit(&block->mutex);
 
 		switch (freed) {
@@ -636,7 +640,7 @@ buf_LRU_free_from_common_LRU_list(
 
 		mutex_enter(block_mutex);
 		accessed = buf_page_is_accessed(bpage);
-		freed = buf_LRU_free_block(bpage, TRUE, NULL);
+		freed = buf_LRU_free_block(bpage, TRUE);
 		mutex_exit(block_mutex);
 
 		switch (freed) {
@@ -798,10 +802,8 @@ LRU list to the free list.
 @return	the free control block, in state BUF_BLOCK_READY_FOR_USE */
 UNIV_INTERN
 buf_block_t*
-buf_LRU_get_free_block(
-/*===================*/
-	ulint	zip_size)	/*!< in: compressed page size in bytes,
-				or 0 if uncompressed tablespace */
+buf_LRU_get_free_block(void)
+/*========================*/
 {
 	buf_block_t*	block		= NULL;
 	ibool		freed;
@@ -877,26 +879,10 @@ loop:
 
 	/* If there is a block in the free list, take it */
 	block = buf_LRU_get_free_only();
-	if (block) {
-
-#ifdef UNIV_DEBUG
-		block->page.zip.m_start =
-#endif /* UNIV_DEBUG */
-			block->page.zip.m_end =
-			block->page.zip.m_nonempty =
-			block->page.zip.n_blobs = 0;
-
-		if (UNIV_UNLIKELY(zip_size)) {
-			ibool	lru;
-			page_zip_set_size(&block->page.zip, zip_size);
-			block->page.zip.data = buf_buddy_alloc(zip_size, &lru);
-			UNIV_MEM_DESC(block->page.zip.data, zip_size, block);
-		} else {
-			page_zip_set_size(&block->page.zip, 0);
-			block->page.zip.data = NULL;
-		}
+	buf_pool_mutex_exit();
 
-		buf_pool_mutex_exit();
+	if (block) {
+		memset(&block->page.zip, 0, sizeof block->page.zip);
 
 		if (started_monitor) {
 			srv_print_innodb_monitor = mon_value_was;
@@ -908,8 +894,6 @@ loop:
 	/* If no block was in the free list, search from the end of the LRU
 	list and try to free a block there */
 
-	buf_pool_mutex_exit();
-
 	freed = buf_LRU_search_and_free_block(n_iterations);
 
 	if (freed > 0) {
@@ -1378,12 +1362,8 @@ enum buf_lru_free_block_status
 buf_LRU_free_block(
 /*===============*/
 	buf_page_t*	bpage,	/*!< in: block to be freed */
-	ibool		zip,	/*!< in: TRUE if should remove also the
+	ibool		zip)	/*!< in: TRUE if should remove also the
 				compressed page of an uncompressed page */
-	ibool*		buf_pool_mutex_released)
-				/*!< in: pointer to a variable that will
-				be assigned TRUE if buf_pool_mutex
-				was temporarily released, or NULL */
 {
 	buf_page_t*	b = NULL;
 	mutex_t*	block_mutex = buf_page_get_mutex(bpage);
@@ -1554,10 +1534,6 @@ alloc:
 			b->io_fix = BUF_IO_READ;
 		}
 
-		if (buf_pool_mutex_released) {
-			*buf_pool_mutex_released = TRUE;
-		}
-
 		buf_pool_mutex_exit();
 		mutex_exit(block_mutex);
 
@@ -1827,6 +1803,7 @@ buf_LRU_block_remove_hashed_page(
 		buf_pool_mutex_exit_forbid();
 		buf_buddy_free(bpage->zip.data,
 			       page_zip_get_size(&bpage->zip));
+		bpage->state = BUF_BLOCK_ZIP_FREE;
 		buf_buddy_free(bpage, sizeof(*bpage));
 		buf_pool_mutex_exit_allow();
 		UNIV_MEM_UNDESC(bpage);
diff --git a/storage/innodb_plugin/dict/dict0dict.c b/storage/innodb_plugin/dict/dict0dict.c
index 9474ab3582a..a8787bbda61 100644
--- a/storage/innodb_plugin/dict/dict0dict.c
+++ b/storage/innodb_plugin/dict/dict0dict.c
@@ -1669,6 +1669,12 @@ undo_size_ok:
 			new_index->heap,
 			(1 + dict_index_get_n_unique(new_index))
 			* sizeof(ib_int64_t));
+
+		new_index->stat_n_non_null_key_vals = mem_heap_zalloc(
+			new_index->heap,
+			(1 + dict_index_get_n_unique(new_index))
+			* sizeof(*new_index->stat_n_non_null_key_vals));
+
 		/* Give some sensible values to stat_n_... in case we do
 		not calculate statistics quickly enough */
 
@@ -4291,6 +4297,10 @@ dict_update_statistics(
 			for (i = dict_index_get_n_unique(index); i; ) {
 				index->stat_n_diff_key_vals[i--] = 1;
 			}
+
+			memset(index->stat_n_non_null_key_vals, 0,
+			       (1 + dict_index_get_n_unique(index))
+                               * sizeof(*index->stat_n_non_null_key_vals));
 		}
 
 		index = dict_table_get_next_index(index);
diff --git a/storage/innodb_plugin/dict/dict0mem.c b/storage/innodb_plugin/dict/dict0mem.c
index 3287247029f..aef815dd2f6 100644
--- a/storage/innodb_plugin/dict/dict0mem.c
+++ b/storage/innodb_plugin/dict/dict0mem.c
@@ -36,6 +36,9 @@ Created 1/8/1996 Heikki Tuuri
 #ifndef UNIV_HOTBACKUP
 # include "lock0lock.h"
 #endif /* !UNIV_HOTBACKUP */
+#ifdef UNIV_BLOB_DEBUG
+# include "ut0rbt.h"
+#endif /* UNIV_BLOB_DEBUG */
 
 #define	DICT_HEAP_SIZE		100	/*!< initial memory heap size when
 					creating a table or index object */
@@ -316,6 +319,12 @@ dict_mem_index_free(
 {
 	ut_ad(index);
 	ut_ad(index->magic_n == DICT_INDEX_MAGIC_N);
+#ifdef UNIV_BLOB_DEBUG
+	if (index->blobs) {
+		mutex_free(&index->blobs_mutex);
+		rbt_free(index->blobs);
+	}
+#endif /* UNIV_BLOB_DEBUG */
 
 	mem_heap_free(index->heap);
 }
diff --git a/storage/innodb_plugin/fsp/fsp0fsp.c b/storage/innodb_plugin/fsp/fsp0fsp.c
index e9d24b8fdf6..d091a14c474 100644
--- a/storage/innodb_plugin/fsp/fsp0fsp.c
+++ b/storage/innodb_plugin/fsp/fsp0fsp.c
@@ -3444,9 +3444,9 @@ fseg_free_page(
 
 	fseg_free_page_low(seg_inode, space, zip_size, page, mtr);
 
-#ifdef UNIV_DEBUG_FILE_ACCESSES
+#if defined UNIV_DEBUG_FILE_ACCESSES || defined UNIV_DEBUG
 	buf_page_set_file_page_was_freed(space, page);
-#endif
+#endif /* UNIV_DEBUG_FILE_ACCESSES || UNIV_DEBUG */
 }
 
 /**********************************************************************//**
@@ -3513,13 +3513,13 @@ fseg_free_extent(
 
 	fsp_free_extent(space, zip_size, page, mtr);
 
-#ifdef UNIV_DEBUG_FILE_ACCESSES
+#if defined UNIV_DEBUG_FILE_ACCESSES || defined UNIV_DEBUG
 	for (i = 0; i < FSP_EXTENT_SIZE; i++) {
 
 		buf_page_set_file_page_was_freed(space,
 						 first_page_in_extent + i);
 	}
-#endif
+#endif /* UNIV_DEBUG_FILE_ACCESSES || UNIV_DEBUG */
 }
 
 /**********************************************************************//**
diff --git a/storage/innodb_plugin/handler/ha_innodb.cc b/storage/innodb_plugin/handler/ha_innodb.cc
index 18a25fd8c4e..481b89ce0d1 100644
--- a/storage/innodb_plugin/handler/ha_innodb.cc
+++ b/storage/innodb_plugin/handler/ha_innodb.cc
@@ -174,6 +174,25 @@ static char*	internal_innobase_data_file_path	= NULL;
 
 static char*	innodb_version_str = (char*) INNODB_VERSION_STR;
 
+/** Possible values for system variable "innodb_stats_method". The values
+are defined the same as its corresponding MyISAM system variable
+"myisam_stats_method"(see "myisam_stats_method_names"), for better usability */
+static const char* innodb_stats_method_names[] = {
+	"nulls_equal",
+	"nulls_unequal",
+	"nulls_ignored",
+	NullS
+};
+
+/** Used to define an enumerate type of the system variable innodb_stats_method.
+This is the same as "myisam_stats_method_typelib" */
+static TYPELIB innodb_stats_method_typelib = {
+	array_elements(innodb_stats_method_names) - 1,
+	"innodb_stats_method_typelib",
+	innodb_stats_method_names,
+	NULL
+};
+
 /* The following counter is used to convey information to InnoDB
 about server activity: in selects it is not sensible to call
 srv_active_wake_master_thread after each fetch or search, we only do
@@ -7518,6 +7537,65 @@ innobase_get_mysql_key_number_for_index(
 
         return(0);
 }
+
+/*********************************************************************//**
+Calculate Record Per Key value. Need to exclude the NULL value if
+innodb_stats_method is set to "nulls_ignored"
+@return estimated record per key value */
+static
+ha_rows
+innodb_rec_per_key(
+/*===============*/
+	dict_index_t*	index,		/*!< in: dict_index_t structure */
+	ulint		i,		/*!< in: the column we are
+					calculating rec per key */
+	ha_rows		records)	/*!< in: estimated total records */
+{
+	ha_rows		rec_per_key;
+
+	ut_ad(i < dict_index_get_n_unique(index));
+
+	/* Note the stat_n_diff_key_vals[] stores the diff value with
+	n-prefix indexing, so it is always stat_n_diff_key_vals[i + 1] */
+	if (index->stat_n_diff_key_vals[i + 1] == 0) {
+
+		rec_per_key = records;
+	} else if (srv_innodb_stats_method == SRV_STATS_NULLS_IGNORED) {
+		ib_int64_t	num_null;
+
+		/* Number of rows with NULL value in this
+		field */
+		num_null = records - index->stat_n_non_null_key_vals[i];
+
+		/* In theory, index->stat_n_non_null_key_vals[i]
+		should always be less than the number of records.
+		Since this is statistics value, the value could
+		have slight discrepancy. But we will make sure
+		the number of null values is not a negative number. */
+		num_null = (num_null < 0) ? 0 : num_null;
+
+		/* If the number of NULL values is the same as or
+		large than that of the distinct values, we could
+		consider that the table consists mostly of NULL value. 
+		Set rec_per_key to 1. */
+		if (index->stat_n_diff_key_vals[i + 1] <= num_null) {
+			rec_per_key = 1;
+		} else {
+			/* Need to exclude rows with NULL values from
+			rec_per_key calculation */
+			rec_per_key = (ha_rows)(
+				(records - num_null)
+				/ (index->stat_n_diff_key_vals[i + 1]
+				   - num_null));
+		}
+	} else {
+		rec_per_key = (ha_rows)
+			 (records / index->stat_n_diff_key_vals[i + 1]);
+	}
+
+	return(rec_per_key);
+}
+
 /*********************************************************************//**
 Returns statistics information of the table to the MySQL interpreter,
 in various fields of the handle object. */
@@ -7748,13 +7826,8 @@ ha_innobase::info_low(
 					break;
 				}
 
-				if (index->stat_n_diff_key_vals[j + 1] == 0) {
-
-					rec_per_key = stats.records;
-				} else {
-					rec_per_key = (ha_rows)(stats.records /
-					 index->stat_n_diff_key_vals[j + 1]);
-				}
+				rec_per_key = innodb_rec_per_key(
+					index, j, stats.records);
 
 				/* Since MySQL seems to favor table scans
 				too much over index searches, we pretend
@@ -10945,6 +11018,13 @@ static MYSQL_SYSVAR_STR(change_buffering, innobase_change_buffering,
   innodb_change_buffering_validate,
   innodb_change_buffering_update, "inserts"); 
 
+static MYSQL_SYSVAR_ENUM(stats_method, srv_innodb_stats_method,
+   PLUGIN_VAR_RQCMDARG,
+  "Specifies how InnoDB index statistics collection code should "
+  "treat NULLs. Possible values are NULLS_EQUAL (default), "
+  "NULLS_UNEQUAL and NULLS_IGNORED",
+   NULL, NULL, SRV_STATS_NULLS_EQUAL, &innodb_stats_method_typelib);
+
 #if defined UNIV_DEBUG || defined UNIV_IBUF_DEBUG
 static MYSQL_SYSVAR_UINT(change_buffering_debug, ibuf_debug,
   PLUGIN_VAR_RQCMDARG,
@@ -10999,6 +11079,7 @@ static struct st_mysql_sys_var* innobase_system_variables[]= {
   MYSQL_SYSVAR(stats_on_metadata),
   MYSQL_SYSVAR(stats_sample_pages),
   MYSQL_SYSVAR(adaptive_hash_index),
+  MYSQL_SYSVAR(stats_method),
   MYSQL_SYSVAR(replication_delay),
   MYSQL_SYSVAR(status_file),
   MYSQL_SYSVAR(strict_mode),
diff --git a/storage/innodb_plugin/handler/handler0alter.cc b/storage/innodb_plugin/handler/handler0alter.cc
index 517445f7e69..dc1317d5c5a 100644
--- a/storage/innodb_plugin/handler/handler0alter.cc
+++ b/storage/innodb_plugin/handler/handler0alter.cc
@@ -782,10 +782,6 @@ err_exit:
 
 	ut_ad(error == DB_SUCCESS);
 
-	/* We will need to rebuild index translation table. Set
-	valid index entry count in the translation table to zero */
-	share->idx_trans_tbl.index_count = 0;
-
 	/* Commit the data dictionary transaction in order to release
 	the table locks on the system tables.  This means that if
 	MySQL crashes while creating a new primary key inside
@@ -911,6 +907,14 @@ error:
 		}
 
 convert_error:
+		if (error == DB_SUCCESS) {
+			/* Build index is successful. We will need to
+			rebuild index translation table.  Reset the
+			index entry count in the translation table
+			to zero, so that translation table will be rebuilt */
+			share->idx_trans_tbl.index_count = 0;
+		}
+
 		error = convert_error_code_to_mysql(error,
 						    innodb_table->flags,
 						    user_thd);
diff --git a/storage/innodb_plugin/ibuf/ibuf0ibuf.c b/storage/innodb_plugin/ibuf/ibuf0ibuf.c
index 701e8f0ef04..23981ac388e 100644
--- a/storage/innodb_plugin/ibuf/ibuf0ibuf.c
+++ b/storage/innodb_plugin/ibuf/ibuf0ibuf.c
@@ -1878,9 +1878,9 @@ ibuf_remove_free_page(void)
 	fseg_free_page(header_page + IBUF_HEADER + IBUF_TREE_SEG_HEADER,
 		       IBUF_SPACE_ID, page_no, &mtr);
 
-#ifdef UNIV_DEBUG_FILE_ACCESSES
+#if defined UNIV_DEBUG_FILE_ACCESSES || defined UNIV_DEBUG
 	buf_page_reset_file_page_was_freed(IBUF_SPACE_ID, page_no);
-#endif
+#endif /* UNIV_DEBUG_FILE_ACCESSES || UNIV_DEBUG */
 
 	ibuf_enter();
 
@@ -1922,9 +1922,9 @@ ibuf_remove_free_page(void)
 	ibuf_bitmap_page_set_bits(
 		bitmap_page, page_no, zip_size, IBUF_BITMAP_IBUF, FALSE, &mtr);
 
-#ifdef UNIV_DEBUG_FILE_ACCESSES
+#if defined UNIV_DEBUG_FILE_ACCESSES || defined UNIV_DEBUG
 	buf_page_set_file_page_was_freed(IBUF_SPACE_ID, page_no);
-#endif
+#endif /* UNIV_DEBUG_FILE_ACCESSES || UNIV_DEBUG */
 	mtr_commit(&mtr);
 
 	mutex_exit(&ibuf_mutex);
diff --git a/storage/innodb_plugin/include/btr0btr.h b/storage/innodb_plugin/include/btr0btr.h
index dde3a0bab69..5aa02694e0e 100644
--- a/storage/innodb_plugin/include/btr0btr.h
+++ b/storage/innodb_plugin/include/btr0btr.h
@@ -81,6 +81,91 @@ UNIQUE definition on secondary indexes when we decide if we can use
 the insert buffer to speed up inserts */
 #define BTR_IGNORE_SEC_UNIQUE	2048
 
+#ifdef UNIV_BLOB_DEBUG
+# include "ut0rbt.h"
+/** An index->blobs entry for keeping track of off-page column references */
+struct btr_blob_dbg_struct
+{
+	unsigned	blob_page_no:32;	/*!< first BLOB page number */
+	unsigned	ref_page_no:32;		/*!< referring page number */
+	unsigned	ref_heap_no:16;		/*!< referring heap number */
+	unsigned	ref_field_no:10;	/*!< referring field number */
+	unsigned	owner:1;		/*!< TRUE if BLOB owner */
+	unsigned	always_owner:1;		/*!< TRUE if always
+						has been the BLOB owner;
+						reset to TRUE on B-tree
+						page splits and merges */
+	unsigned	del:1;			/*!< TRUE if currently
+						delete-marked */
+};
+
+/**************************************************************//**
+Add a reference to an off-page column to the index->blobs map. */
+UNIV_INTERN
+void
+btr_blob_dbg_add_blob(
+/*==================*/
+	const rec_t*	rec,		/*!< in: clustered index record */
+	ulint		field_no,	/*!< in: number of off-page column */
+	ulint		page_no,	/*!< in: start page of the column */
+	dict_index_t*	index,		/*!< in/out: index tree */
+	const char*	ctx)		/*!< in: context (for logging) */
+	__attribute__((nonnull));
+/**************************************************************//**
+Display the references to off-page columns.
+This function is to be called from a debugger,
+for example when a breakpoint on ut_dbg_assertion_failed is hit. */
+UNIV_INTERN
+void
+btr_blob_dbg_print(
+/*===============*/
+	const dict_index_t*	index)	/*!< in: index tree */
+	__attribute__((nonnull));
+/**************************************************************//**
+Check that there are no references to off-page columns from or to
+the given page. Invoked when freeing or clearing a page.
+@return TRUE when no orphan references exist */
+UNIV_INTERN
+ibool
+btr_blob_dbg_is_empty(
+/*==================*/
+	dict_index_t*	index,		/*!< in: index */
+	ulint		page_no)	/*!< in: page number */
+	__attribute__((nonnull, warn_unused_result));
+
+/**************************************************************//**
+Modify the 'deleted' flag of a record. */
+UNIV_INTERN
+void
+btr_blob_dbg_set_deleted_flag(
+/*==========================*/
+	const rec_t*		rec,	/*!< in: record */
+	dict_index_t*		index,	/*!< in/out: index */
+	const ulint*		offsets,/*!< in: rec_get_offs(rec, index) */
+	ibool			del)	/*!< in: TRUE=deleted, FALSE=exists */
+	__attribute__((nonnull));
+/**************************************************************//**
+Change the ownership of an off-page column. */
+UNIV_INTERN
+void
+btr_blob_dbg_owner(
+/*===============*/
+	const rec_t*		rec,	/*!< in: record */
+	dict_index_t*		index,	/*!< in/out: index */
+	const ulint*		offsets,/*!< in: rec_get_offs(rec, index) */
+	ulint			i,	/*!< in: ith field in rec */
+	ibool			own)	/*!< in: TRUE=owned, FALSE=disowned */
+	__attribute__((nonnull));
+/** Assert that there are no BLOB references to or from the given page. */
+# define btr_blob_dbg_assert_empty(index, page_no)	\
+	ut_a(btr_blob_dbg_is_empty(index, page_no))
+#else /* UNIV_BLOB_DEBUG */
+# define btr_blob_dbg_add_blob(rec, field_no, page, index, ctx)	((void) 0)
+# define btr_blob_dbg_set_deleted_flag(rec, index, offsets, del)((void) 0)
+# define btr_blob_dbg_owner(rec, index, offsets, i, val)	((void) 0)
+# define btr_blob_dbg_assert_empty(index, page_no)		((void) 0)
+#endif /* UNIV_BLOB_DEBUG */
+
 /**************************************************************//**
 Gets the root node of a tree and x-latches it.
 @return	root page, x-latched */
diff --git a/storage/innodb_plugin/include/btr0cur.h b/storage/innodb_plugin/include/btr0cur.h
index b477ad0320a..ece3621fa97 100644
--- a/storage/innodb_plugin/include/btr0cur.h
+++ b/storage/innodb_plugin/include/btr0cur.h
@@ -478,7 +478,10 @@ btr_estimate_n_rows_in_range(
 /*******************************************************************//**
 Estimates the number of different key values in a given index, for
 each n-column prefix of the index where n <= dict_index_get_n_unique(index).
-The estimates are stored in the array index->stat_n_diff_key_vals. */
+The estimates are stored in the array index->stat_n_diff_key_vals.
+If innodb_stats_method is nulls_ignored, we also record the number of
+non-null values for each prefix and stored the estimates in
+array index->stat_n_non_null_key_vals. */
 UNIV_INTERN
 void
 btr_estimate_number_of_different_key_vals(
@@ -509,8 +512,8 @@ file segment of the index tree.
 @return	DB_SUCCESS or DB_OUT_OF_FILE_SPACE */
 UNIV_INTERN
 ulint
-btr_store_big_rec_extern_fields(
-/*============================*/
+btr_store_big_rec_extern_fields_func(
+/*=================================*/
 	dict_index_t*	index,		/*!< in: index of rec; the index tree
 					MUST be X-latched */
 	buf_block_t*	rec_block,	/*!< in/out: block containing rec */
@@ -519,10 +522,42 @@ btr_store_big_rec_extern_fields(
 					the "external storage" flags in offsets
 					will not correspond to rec when
 					this function returns */
-	big_rec_t*	big_rec_vec,	/*!< in: vector containing fields
+#ifdef UNIV_DEBUG
+	mtr_t*		local_mtr,	/*!< in: mtr containing the
+					latch to rec and to the tree */
+#endif /* UNIV_DEBUG */
+#if defined UNIV_DEBUG || defined UNIV_BLOB_LIGHT_DEBUG
+	ibool		update_in_place,/*! in: TRUE if the record is updated
+					in place (not delete+insert) */
+#endif /* UNIV_DEBUG || UNIV_BLOB_LIGHT_DEBUG */
+	const big_rec_t*big_rec_vec)	/*!< in: vector containing fields
 					to be stored externally */
-	mtr_t*		local_mtr);	/*!< in: mtr containing the latch to
-					rec and to the tree */
+	__attribute__((nonnull));
+
+/** Stores the fields in big_rec_vec to the tablespace and puts pointers to
+them in rec.  The extern flags in rec will have to be set beforehand.
+The fields are stored on pages allocated from leaf node
+file segment of the index tree.
+@param index	in: clustered index; MUST be X-latched by mtr
+@param b	in/out: block containing rec; MUST be X-latched by mtr
+@param rec	in/out: clustered index record
+@param offsets	in: rec_get_offsets(rec, index);
+		the "external storage" flags in offsets will not be adjusted
+@param mtr	in: mini-transaction that holds x-latch on index and b
+@param upd	in: TRUE if the record is updated in place (not delete+insert)
+@param big	in: vector containing fields to be stored externally
+@return	DB_SUCCESS or DB_OUT_OF_FILE_SPACE */
+#ifdef UNIV_DEBUG
+# define btr_store_big_rec_extern_fields(index,b,rec,offsets,mtr,upd,big) \
+	btr_store_big_rec_extern_fields_func(index,b,rec,offsets,mtr,upd,big)
+#elif defined UNIV_BLOB_LIGHT_DEBUG
+# define btr_store_big_rec_extern_fields(index,b,rec,offsets,mtr,upd,big) \
+	btr_store_big_rec_extern_fields_func(index,b,rec,offsets,upd,big)
+#else
+# define btr_store_big_rec_extern_fields(index,b,rec,offsets,mtr,upd,big) \
+	btr_store_big_rec_extern_fields_func(index,b,rec,offsets,big)
+#endif
+
 /*******************************************************************//**
 Frees the space in an externally stored field to the file space
 management if the field in data is owned the externally stored field,
diff --git a/storage/innodb_plugin/include/btr0types.h b/storage/innodb_plugin/include/btr0types.h
index ef4a6b04b34..07c06fb18d7 100644
--- a/storage/innodb_plugin/include/btr0types.h
+++ b/storage/innodb_plugin/include/btr0types.h
@@ -38,6 +38,131 @@ typedef struct btr_cur_struct		btr_cur_t;
 /** B-tree search information for the adaptive hash index */
 typedef struct btr_search_struct	btr_search_t;
 
+#ifdef UNIV_BLOB_DEBUG
+# include "buf0types.h"
+/** An index->blobs entry for keeping track of off-page column references */
+typedef struct btr_blob_dbg_struct btr_blob_dbg_t;
+
+/** Insert to index->blobs a reference to an off-page column.
+@param index	the index tree
+@param b	the reference
+@param ctx	context (for logging) */
+UNIV_INTERN
+void
+btr_blob_dbg_rbt_insert(
+/*====================*/
+	dict_index_t*		index,	/*!< in/out: index tree */
+	const btr_blob_dbg_t*	b,	/*!< in: the reference */
+	const char*		ctx)	/*!< in: context (for logging) */
+	__attribute__((nonnull));
+
+/** Remove from index->blobs a reference to an off-page column.
+@param index	the index tree
+@param b	the reference
+@param ctx	context (for logging) */
+UNIV_INTERN
+void
+btr_blob_dbg_rbt_delete(
+/*====================*/
+	dict_index_t*		index,	/*!< in/out: index tree */
+	const btr_blob_dbg_t*	b,	/*!< in: the reference */
+	const char*		ctx)	/*!< in: context (for logging) */
+	__attribute__((nonnull));
+
+/**************************************************************//**
+Add to index->blobs any references to off-page columns from a record.
+@return number of references added */
+UNIV_INTERN
+ulint
+btr_blob_dbg_add_rec(
+/*=================*/
+	const rec_t*	rec,	/*!< in: record */
+	dict_index_t*	index,	/*!< in/out: index */
+	const ulint*	offsets,/*!< in: offsets */
+	const char*	ctx)	/*!< in: context (for logging) */
+	__attribute__((nonnull));
+/**************************************************************//**
+Remove from index->blobs any references to off-page columns from a record.
+@return number of references removed */
+UNIV_INTERN
+ulint
+btr_blob_dbg_remove_rec(
+/*====================*/
+	const rec_t*	rec,	/*!< in: record */
+	dict_index_t*	index,	/*!< in/out: index */
+	const ulint*	offsets,/*!< in: offsets */
+	const char*	ctx)	/*!< in: context (for logging) */
+	__attribute__((nonnull));
+/**************************************************************//**
+Count and add to index->blobs any references to off-page columns
+from records on a page.
+@return number of references added */
+UNIV_INTERN
+ulint
+btr_blob_dbg_add(
+/*=============*/
+	const page_t*	page,	/*!< in: rewritten page */
+	dict_index_t*	index,	/*!< in/out: index */
+	const char*	ctx)	/*!< in: context (for logging) */
+	__attribute__((nonnull));
+/**************************************************************//**
+Count and remove from index->blobs any references to off-page columns
+from records on a page.
+Used when reorganizing a page, before copying the records.
+@return number of references removed */
+UNIV_INTERN
+ulint
+btr_blob_dbg_remove(
+/*================*/
+	const page_t*	page,	/*!< in: b-tree page */
+	dict_index_t*	index,	/*!< in/out: index */
+	const char*	ctx)	/*!< in: context (for logging) */
+	__attribute__((nonnull));
+/**************************************************************//**
+Restore in index->blobs any references to off-page columns
+Used when page reorganize fails due to compressed page overflow. */
+UNIV_INTERN
+void
+btr_blob_dbg_restore(
+/*=================*/
+	const page_t*	npage,	/*!< in: page that failed to compress */
+	const page_t*	page,	/*!< in: copy of original page */
+	dict_index_t*	index,	/*!< in/out: index */
+	const char*	ctx)	/*!< in: context (for logging) */
+	__attribute__((nonnull));
+
+/** Operation that processes the BLOB references of an index record
+@param[in]	rec	record on index page
+@param[in/out]	index	the index tree of the record
+@param[in]	offsets	rec_get_offsets(rec,index)
+@param[in]	ctx	context (for logging)
+@return			number of BLOB references processed */
+typedef ulint (*btr_blob_dbg_op_f)
+(const rec_t* rec,dict_index_t* index,const ulint* offsets,const char* ctx);
+
+/**************************************************************//**
+Count and process all references to off-page columns on a page.
+@return number of references processed */
+UNIV_INTERN
+ulint
+btr_blob_dbg_op(
+/*============*/
+	const page_t*		page,	/*!< in: B-tree leaf page */
+	const rec_t*		rec,	/*!< in: record to start from
+					(NULL to process the whole page) */
+	dict_index_t*		index,	/*!< in/out: index */
+	const char*		ctx,	/*!< in: context (for logging) */
+	const btr_blob_dbg_op_f	op)	/*!< in: operation on records */
+	__attribute__((nonnull(1,3,4,5)));
+#else /* UNIV_BLOB_DEBUG */
+# define btr_blob_dbg_add_rec(rec, index, offsets, ctx)		((void) 0)
+# define btr_blob_dbg_add(page, index, ctx)			((void) 0)
+# define btr_blob_dbg_remove_rec(rec, index, offsets, ctx)	((void) 0)
+# define btr_blob_dbg_remove(page, index, ctx)			((void) 0)
+# define btr_blob_dbg_restore(npage, page, index, ctx)		((void) 0)
+# define btr_blob_dbg_op(page, rec, index, ctx, op)		((void) 0)
+#endif /* UNIV_BLOB_DEBUG */
+
 /** The size of a reference to data stored on a different page.
 The reference is stored at the end of the prefix of the field
 in the index record. */
diff --git a/storage/innodb_plugin/include/buf0buf.h b/storage/innodb_plugin/include/buf0buf.h
index cd4ee5906f0..05dead5ac9e 100644
--- a/storage/innodb_plugin/include/buf0buf.h
+++ b/storage/innodb_plugin/include/buf0buf.h
@@ -41,6 +41,8 @@ Created 11/5/1995 Heikki Tuuri
 /* @{ */
 #define BUF_GET			10	/*!< get always */
 #define	BUF_GET_IF_IN_POOL	11	/*!< get if in pool */
+#define BUF_PEEK_IF_IN_POOL	12	/*!< get if in pool, do not make
+					the block young in the LRU list */
 #define BUF_GET_NO_LATCH	14	/*!< get and bufferfix, but
 					set no latch; we have
 					separated this case, because
@@ -165,10 +167,8 @@ Allocates a buffer block.
 @return	own: the allocated block, in state BUF_BLOCK_MEMORY */
 UNIV_INLINE
 buf_block_t*
-buf_block_alloc(
-/*============*/
-	ulint	zip_size);	/*!< in: compressed page size in bytes,
-				or 0 if uncompressed tablespace */
+buf_block_alloc(void);
+/*=================*/
 /********************************************************************//**
 Frees a buffer block which does not contain a file page. */
 UNIV_INLINE
@@ -286,7 +286,7 @@ buf_page_get_gen(
 	ulint		rw_latch,/*!< in: RW_S_LATCH, RW_X_LATCH, RW_NO_LATCH */
 	buf_block_t*	guess,	/*!< in: guessed block or NULL */
 	ulint		mode,	/*!< in: BUF_GET, BUF_GET_IF_IN_POOL,
-				BUF_GET_NO_LATCH */
+				BUF_PEEK_IF_IN_POOL, BUF_GET_NO_LATCH */
 	const char*	file,	/*!< in: file name */
 	ulint		line,	/*!< in: line where called */
 	mtr_t*		mtr);	/*!< in: mini-transaction */
@@ -370,7 +370,7 @@ buf_reset_check_index_page_at_flush(
 /*================================*/
 	ulint	space,	/*!< in: space id */
 	ulint	offset);/*!< in: page number */
-#ifdef UNIV_DEBUG_FILE_ACCESSES
+#if defined UNIV_DEBUG_FILE_ACCESSES || defined UNIV_DEBUG
 /********************************************************************//**
 Sets file_page_was_freed TRUE if the page is found in the buffer pool.
 This function should be called when we free a file page and want the
@@ -395,7 +395,7 @@ buf_page_reset_file_page_was_freed(
 /*===============================*/
 	ulint	space,	/*!< in: space id */
 	ulint	offset);	/*!< in: page number */
-#endif /* UNIV_DEBUG_FILE_ACCESSES */
+#endif /* UNIV_DEBUG_FILE_ACCESSES || UNIV_DEBUG */
 /********************************************************************//**
 Reads the freed_page_clock of a buffer block.
 @return	freed_page_clock */
@@ -1137,11 +1137,11 @@ struct buf_page_struct{
 					0 if the block was never accessed
 					in the buffer pool */
 	/* @} */
-# ifdef UNIV_DEBUG_FILE_ACCESSES
+# if defined UNIV_DEBUG_FILE_ACCESSES || defined UNIV_DEBUG
 	ibool		file_page_was_freed;
 					/*!< this is set to TRUE when fsp
 					frees a page in buffer pool */
-# endif /* UNIV_DEBUG_FILE_ACCESSES */
+# endif /* UNIV_DEBUG_FILE_ACCESSES || UNIV_DEBUG */
 #endif /* !UNIV_HOTBACKUP */
 };
 
diff --git a/storage/innodb_plugin/include/buf0buf.ic b/storage/innodb_plugin/include/buf0buf.ic
index 23db684806c..0025bef5aac 100644
--- a/storage/innodb_plugin/include/buf0buf.ic
+++ b/storage/innodb_plugin/include/buf0buf.ic
@@ -719,14 +719,12 @@ Allocates a buffer block.
 @return	own: the allocated block, in state BUF_BLOCK_MEMORY */
 UNIV_INLINE
 buf_block_t*
-buf_block_alloc(
-/*============*/
-	ulint	zip_size)	/*!< in: compressed page size in bytes,
-				or 0 if uncompressed tablespace */
+buf_block_alloc(void)
+/*=================*/
 {
 	buf_block_t*	block;
 
-	block = buf_LRU_get_free_block(zip_size);
+	block = buf_LRU_get_free_block();
 
 	buf_block_set_state(block, BUF_BLOCK_MEMORY);
 
diff --git a/storage/innodb_plugin/include/buf0lru.h b/storage/innodb_plugin/include/buf0lru.h
index 5a9cfd059f3..d543bce53cd 100644
--- a/storage/innodb_plugin/include/buf0lru.h
+++ b/storage/innodb_plugin/include/buf0lru.h
@@ -110,12 +110,9 @@ enum buf_lru_free_block_status
 buf_LRU_free_block(
 /*===============*/
 	buf_page_t*	bpage,	/*!< in: block to be freed */
-	ibool		zip,	/*!< in: TRUE if should remove also the
+	ibool		zip)	/*!< in: TRUE if should remove also the
 				compressed page of an uncompressed page */
-	ibool*		buf_pool_mutex_released);
-				/*!< in: pointer to a variable that will
-				be assigned TRUE if buf_pool_mutex
-				was temporarily released, or NULL */
+	__attribute__((nonnull));
 /******************************************************************//**
 Try to free a replaceable block.
 @return	TRUE if found and freed */
@@ -146,10 +143,9 @@ LRU list to the free list.
 @return	the free control block, in state BUF_BLOCK_READY_FOR_USE */
 UNIV_INTERN
 buf_block_t*
-buf_LRU_get_free_block(
-/*===================*/
-	ulint	zip_size);	/*!< in: compressed page size in bytes,
-				or 0 if uncompressed tablespace */
+buf_LRU_get_free_block(void)
+/*========================*/
+	__attribute__((warn_unused_result));
 
 /******************************************************************//**
 Puts a block back to the free list. */
diff --git a/storage/innodb_plugin/include/dict0mem.h b/storage/innodb_plugin/include/dict0mem.h
index 19782c2e76a..bd32a239cfd 100644
--- a/storage/innodb_plugin/include/dict0mem.h
+++ b/storage/innodb_plugin/include/dict0mem.h
@@ -321,6 +321,12 @@ struct dict_index_struct{
 				dict_get_n_unique(index); we
 				periodically calculate new
 				estimates */
+	ib_int64_t*	stat_n_non_null_key_vals;
+				/* approximate number of non-null key values
+				for this index, for each column where
+				n < dict_get_n_unique(index); This
+				is used when innodb_stats_method is
+				"nulls_ignored". */
 	ulint		stat_index_size;
 				/*!< approximate index size in
 				database pages */
@@ -334,6 +340,13 @@ struct dict_index_struct{
 				index, or 0 if the index existed
 				when InnoDB was started up */
 #endif /* !UNIV_HOTBACKUP */
+#ifdef UNIV_BLOB_DEBUG
+	mutex_t		blobs_mutex;
+				/*!< mutex protecting blobs */
+	void*		blobs;	/*!< map of (page_no,heap_no,field_no)
+				to first_blob_page_no; protected by
+				blobs_mutex; @see btr_blob_dbg_t */
+#endif /* UNIV_BLOB_DEBUG */
 #ifdef UNIV_DEBUG
 	ulint		magic_n;/*!< magic number */
 /** Value of dict_index_struct::magic_n */
diff --git a/storage/innodb_plugin/include/dict0types.h b/storage/innodb_plugin/include/dict0types.h
index 7ad69193cc9..f14b59a19d4 100644
--- a/storage/innodb_plugin/include/dict0types.h
+++ b/storage/innodb_plugin/include/dict0types.h
@@ -33,11 +33,6 @@ typedef struct dict_index_struct	dict_index_t;
 typedef struct dict_table_struct	dict_table_t;
 typedef struct dict_foreign_struct	dict_foreign_t;
 
-/* A cluster object is a table object with the type field set to
-DICT_CLUSTERED */
-
-typedef dict_table_t			dict_cluster_t;
-
 typedef struct ind_node_struct		ind_node_t;
 typedef struct tab_node_struct		tab_node_t;
 
diff --git a/storage/innodb_plugin/include/page0zip.h b/storage/innodb_plugin/include/page0zip.h
index 574809e5227..00c1d0516e6 100644
--- a/storage/innodb_plugin/include/page0zip.h
+++ b/storage/innodb_plugin/include/page0zip.h
@@ -420,7 +420,7 @@ page_zip_copy_recs(
 	const page_t*		src,		/*!< in: page */
 	dict_index_t*		index,		/*!< in: index of the B-tree */
 	mtr_t*			mtr)		/*!< in: mini-transaction */
-	__attribute__((nonnull(1,2,3,4)));
+	__attribute__((nonnull));
 #endif /* !UNIV_HOTBACKUP */
 
 /**********************************************************************//**
diff --git a/storage/innodb_plugin/include/rem0cmp.h b/storage/innodb_plugin/include/rem0cmp.h
index 2f751a38864..a908521c9f7 100644
--- a/storage/innodb_plugin/include/rem0cmp.h
+++ b/storage/innodb_plugin/include/rem0cmp.h
@@ -165,6 +165,10 @@ cmp_rec_rec_with_match(
 	const ulint*	offsets1,/*!< in: rec_get_offsets(rec1, index) */
 	const ulint*	offsets2,/*!< in: rec_get_offsets(rec2, index) */
 	dict_index_t*	index,	/*!< in: data dictionary index */
+	ibool		nulls_unequal,
+				/* in: TRUE if this is for index statistics
+				cardinality estimation, and innodb_stats_method
+				is "nulls_unequal" or "nulls_ignored" */
 	ulint*		matched_fields, /*!< in/out: number of already completely
 				matched fields; when the function returns,
 				contains the value the for current
diff --git a/storage/innodb_plugin/include/rem0cmp.ic b/storage/innodb_plugin/include/rem0cmp.ic
index 39ef5f4fba3..63415fe7837 100644
--- a/storage/innodb_plugin/include/rem0cmp.ic
+++ b/storage/innodb_plugin/include/rem0cmp.ic
@@ -87,5 +87,5 @@ cmp_rec_rec(
 	ulint	match_b		= 0;
 
 	return(cmp_rec_rec_with_match(rec1, rec2, offsets1, offsets2, index,
-				      &match_f, &match_b));
+				      FALSE, &match_f, &match_b));
 }
diff --git a/storage/innodb_plugin/include/row0upd.h b/storage/innodb_plugin/include/row0upd.h
index b61e6b6dca1..97b7ec49a17 100644
--- a/storage/innodb_plugin/include/row0upd.h
+++ b/storage/innodb_plugin/include/row0upd.h
@@ -280,19 +280,29 @@ NOTE: we compare the fields as binary strings!
 @return TRUE if update vector changes an ordering field in the index record */
 UNIV_INTERN
 ibool
-row_upd_changes_ord_field_binary(
-/*=============================*/
+row_upd_changes_ord_field_binary_func(
+/*==================================*/
+	dict_index_t*	index,	/*!< in: index of the record */
+	const upd_t*	update,	/*!< in: update vector for the row; NOTE: the
+				field numbers in this MUST be clustered index
+				positions! */
+#ifdef UNIV_DEBUG
+	const que_thr_t*thr,	/*!< in: query thread */
+#endif /* UNIV_DEBUG */
 	const dtuple_t*	row,	/*!< in: old value of row, or NULL if the
 				row and the data values in update are not
 				known when this function is called, e.g., at
 				compile time */
-	const row_ext_t*ext,	/*!< NULL, or prefixes of the externally
+	const row_ext_t*ext)	/*!< NULL, or prefixes of the externally
 				stored columns in the old row */
-	dict_index_t*	index,	/*!< in: index of the record */
-	const upd_t*	update)	/*!< in: update vector for the row; NOTE: the
-				field numbers in this MUST be clustered index
-				positions! */
-	__attribute__((nonnull(3,4), warn_unused_result));
+	__attribute__((nonnull(1,2), warn_unused_result));
+#ifdef UNIV_DEBUG
+# define row_upd_changes_ord_field_binary(index,update,thr,row,ext)	\
+	row_upd_changes_ord_field_binary_func(index,update,thr,row,ext)
+#else /* UNIV_DEBUG */
+# define row_upd_changes_ord_field_binary(index,update,thr,row,ext)	\
+	row_upd_changes_ord_field_binary_func(index,update,row,ext)
+#endif /* UNIV_DEBUG */
 /***********************************************************//**
 Checks if an update vector changes an ordering field of an index record.
 This function is fast if the update vector is short or the number of ordering
diff --git a/storage/innodb_plugin/include/srv0srv.h b/storage/innodb_plugin/include/srv0srv.h
index 7aa2ce74720..91ae895040c 100644
--- a/storage/innodb_plugin/include/srv0srv.h
+++ b/storage/innodb_plugin/include/srv0srv.h
@@ -154,6 +154,11 @@ capacity. PCT_IO(5) -> returns the number of IO operations that
 is 5% of the max where max is srv_io_capacity.  */
 #define PCT_IO(p) ((ulong) (srv_io_capacity * ((double) p / 100.0)))
 
+/* The "innodb_stats_method" setting, decides how InnoDB is going
+to treat NULL value when collecting statistics. It is not defined
+as enum type because the configure option takes unsigned integer type. */
+extern ulong	srv_innodb_stats_method;
+
 #ifdef UNIV_LOG_ARCHIVE
 extern ibool	srv_log_archive_on;
 extern ibool	srv_archive_recovery;
@@ -363,6 +368,19 @@ enum {
 					in connection with recovery */
 };
 
+/* Alternatives for srv_innodb_stats_method, which could be changed by
+setting innodb_stats_method */
+enum srv_stats_method_name_enum {
+	SRV_STATS_NULLS_EQUAL,		/* All NULL values are treated as
+					equal. This is the default setting
+					for innodb_stats_method */
+	SRV_STATS_NULLS_UNEQUAL,	/* All NULL values are treated as
+					NOT equal. */
+	SRV_STATS_NULLS_IGNORED		/* NULL values are ignored */
+};
+
+typedef enum srv_stats_method_name_enum		srv_stats_method_name_t;
+
 #ifndef UNIV_HOTBACKUP
 /** Types of threads existing in the system. */
 enum srv_thread_type {
diff --git a/storage/innodb_plugin/include/sync0arr.h b/storage/innodb_plugin/include/sync0arr.h
index 5f1280f5e28..6e931346238 100644
--- a/storage/innodb_plugin/include/sync0arr.h
+++ b/storage/innodb_plugin/include/sync0arr.h
@@ -115,8 +115,11 @@ Prints warnings of long semaphore waits to stderr.
 @return	TRUE if fatal semaphore wait threshold was exceeded */
 UNIV_INTERN
 ibool
-sync_array_print_long_waits(void);
-/*=============================*/
+sync_array_print_long_waits(
+/*========================*/
+	os_thread_id_t*	waiter,	/*!< out: longest waiting thread */
+	const void**	sema)	/*!< out: longest-waited-for semaphore */
+	__attribute__((nonnull));
 /********************************************************************//**
 Validates the integrity of the wait array. Checks
 that the number of reserved cells equals the count variable. */
diff --git a/storage/innodb_plugin/include/sync0rw.h b/storage/innodb_plugin/include/sync0rw.h
index 175f3deb77c..47f7dbfe0eb 100644
--- a/storage/innodb_plugin/include/sync0rw.h
+++ b/storage/innodb_plugin/include/sync0rw.h
@@ -1,6 +1,6 @@
 /*****************************************************************************
 
-Copyright (c) 1995, 2010, Innobase Oy. All Rights Reserved.
+Copyright (c) 1995, 2011, Oracle and/or its affiliates. All Rights Reserved.
 Copyright (c) 2008, Google Inc.
 
 Portions of this file contain modifications contributed and copyrighted by
@@ -490,6 +490,7 @@ UNIV_INTERN
 void
 rw_lock_debug_print(
 /*================*/
+	FILE*			f,	/*!< in: output stream */
 	rw_lock_debug_t*	info);	/*!< in: debug struct */
 #endif /* UNIV_SYNC_DEBUG */
 
diff --git a/storage/innodb_plugin/include/trx0rseg.h b/storage/innodb_plugin/include/trx0rseg.h
index a25d84f1e84..e3674089735 100644
--- a/storage/innodb_plugin/include/trx0rseg.h
+++ b/storage/innodb_plugin/include/trx0rseg.h
@@ -135,9 +135,7 @@ struct trx_rseg_struct{
 	ulint		id;	/*!< rollback segment id == the index of
 				its slot in the trx system file copy */
 	mutex_t		mutex;	/*!< mutex protecting the fields in this
-				struct except id; NOTE that the latching
-				order must always be kernel mutex ->
-				rseg mutex */
+				struct except id, which is constant */
 	ulint		space;	/*!< space where the rollback segment is
 				header is placed */
 	ulint		zip_size;/* compressed page size of space
diff --git a/storage/innodb_plugin/include/trx0trx.h b/storage/innodb_plugin/include/trx0trx.h
index abd175d365b..833bae4a4ff 100644
--- a/storage/innodb_plugin/include/trx0trx.h
+++ b/storage/innodb_plugin/include/trx0trx.h
@@ -214,12 +214,12 @@ trx_recover_for_mysql(
 /*******************************************************************//**
 This function is used to find one X/Open XA distributed transaction
 which is in the prepared state
-@return	trx or NULL */
+@return	trx or NULL; on match, the trx->xid will be invalidated */
 UNIV_INTERN
 trx_t *
 trx_get_trx_by_xid(
 /*===============*/
-	XID*	xid);	/*!< in: X/Open XA transaction identification */
+	const XID*	xid);	/*!< in: X/Open XA transaction identifier */
 /**********************************************************************//**
 If required, flushes the log to disk if we called trx_commit_for_mysql()
 with trx->flush_log_later == TRUE.
diff --git a/storage/innodb_plugin/include/univ.i b/storage/innodb_plugin/include/univ.i
index b721e0406a8..319db93d137 100644
--- a/storage/innodb_plugin/include/univ.i
+++ b/storage/innodb_plugin/include/univ.i
@@ -46,7 +46,7 @@ Created 1/20/1994 Heikki Tuuri
 
 #define INNODB_VERSION_MAJOR	1
 #define INNODB_VERSION_MINOR	0
-#define INNODB_VERSION_BUGFIX	15
+#define INNODB_VERSION_BUGFIX	16
 
 /* The following is the InnoDB version as shown in
 SELECT plugin_version FROM information_schema.plugins;
@@ -177,14 +177,15 @@ command. Not tested on Windows. */
 						debugging without UNIV_DEBUG */
 #define UNIV_BUF_DEBUG				/* Enable buffer pool
 						debugging without UNIV_DEBUG */
+#define UNIV_BLOB_LIGHT_DEBUG			/* Enable off-page column
+						debugging without UNIV_DEBUG */
 #define UNIV_DEBUG				/* Enable ut_ad() assertions
 						and disable UNIV_INLINE */
 #define UNIV_DEBUG_LOCK_VALIDATE		/* Enable
 						ut_ad(lock_rec_validate_page())
 						assertions. */
-#define UNIV_DEBUG_FILE_ACCESSES		/* Debug .ibd file access
-						(field file_page_was_freed
-						in buf_page_t) */
+#define UNIV_DEBUG_FILE_ACCESSES		/* Enable freed block access
+						debugging without UNIV_DEBUG */
 #define UNIV_LRU_DEBUG				/* debug the buffer pool LRU */
 #define UNIV_HASH_DEBUG				/* debug HASH_ macros */
 #define UNIV_LIST_DEBUG				/* debug UT_LIST_ macros */
@@ -193,6 +194,8 @@ this will break redo log file compatibility, but it may be useful when
 debugging redo log application problems. */
 #define UNIV_MEM_DEBUG				/* detect memory leaks etc */
 #define UNIV_IBUF_DEBUG				/* debug the insert buffer */
+#define UNIV_BLOB_DEBUG				/* track BLOB ownership;
+assumes that no BLOBs survive server restart */
 #define UNIV_IBUF_COUNT_DEBUG			/* debug the insert buffer;
 this limits the database to IBUF_COUNT_N_SPACES and IBUF_COUNT_N_PAGES,
 and the insert buffer must be empty when the database is started */
@@ -424,7 +427,7 @@ it is read or written. */
 /* Use sun_prefetch when compile with Sun Studio */
 # define UNIV_EXPECT(expr,value) (expr)
 # define UNIV_LIKELY_NULL(expr) (expr)
-# define UNIV_PREFETCH_R(addr) sun_prefetch_read_many(addr)
+# define UNIV_PREFETCH_R(addr) sun_prefetch_read_many((void*) addr)
 # define UNIV_PREFETCH_RW(addr) sun_prefetch_write_many(addr)
 #else
 /* Dummy versions of the macros */
diff --git a/storage/innodb_plugin/mem/mem0mem.c b/storage/innodb_plugin/mem/mem0mem.c
index 1dd4db30841..86100b04fd6 100644
--- a/storage/innodb_plugin/mem/mem0mem.c
+++ b/storage/innodb_plugin/mem/mem0mem.c
@@ -347,7 +347,7 @@ mem_heap_create_block(
 				return(NULL);
 			}
 		} else {
-			buf_block = buf_block_alloc(0);
+			buf_block = buf_block_alloc();
 		}
 
 		block = (mem_block_t*) buf_block->frame;
diff --git a/storage/innodb_plugin/mtr/mtr0log.c b/storage/innodb_plugin/mtr/mtr0log.c
index 3f3dab36b76..3349036b5b3 100644
--- a/storage/innodb_plugin/mtr/mtr0log.c
+++ b/storage/innodb_plugin/mtr/mtr0log.c
@@ -408,7 +408,7 @@ mlog_parse_string(
 	ptr += 2;
 
 	if (UNIV_UNLIKELY(offset >= UNIV_PAGE_SIZE)
-			|| UNIV_UNLIKELY(len + offset) > UNIV_PAGE_SIZE) {
+	    || UNIV_UNLIKELY(len + offset > UNIV_PAGE_SIZE)) {
 		recv_sys->found_corrupt_log = TRUE;
 
 		return(NULL);
diff --git a/storage/innodb_plugin/page/page0cur.c b/storage/innodb_plugin/page/page0cur.c
index f10f16a7dd9..936762b986a 100644
--- a/storage/innodb_plugin/page/page0cur.c
+++ b/storage/innodb_plugin/page/page0cur.c
@@ -1149,6 +1149,8 @@ use_heap:
 					      current_rec, index, mtr);
 	}
 
+	btr_blob_dbg_add_rec(insert_rec, index, offsets, "insert");
+
 	return(insert_rec);
 }
 
@@ -1195,10 +1197,12 @@ page_cur_insert_rec_zip_reorg(
 	}
 
 	/* Out of space: restore the page */
+	btr_blob_dbg_remove(page, index, "insert_zip_fail");
 	if (!page_zip_decompress(page_zip, page, FALSE)) {
 		ut_error; /* Memory corrupted? */
 	}
 	ut_ad(page_validate(page, index));
+	btr_blob_dbg_add(page, index, "insert_zip_fail");
 	return(NULL);
 }
 
@@ -1490,6 +1494,8 @@ use_heap:
 
 	page_zip_write_rec(page_zip, insert_rec, index, offsets, 1);
 
+	btr_blob_dbg_add_rec(insert_rec, index, offsets, "insert_zip_ok");
+
 	/* 9. Write log record of the insert */
 	if (UNIV_LIKELY(mtr != NULL)) {
 		page_cur_insert_rec_write_log(insert_rec, rec_size,
@@ -1697,6 +1703,9 @@ page_copy_rec_list_end_to_created_page(
 
 		heap_top += rec_size;
 
+		rec_offs_make_valid(insert_rec, index, offsets);
+		btr_blob_dbg_add_rec(insert_rec, index, offsets, "copy_end");
+
 		page_cur_insert_rec_write_log(insert_rec, rec_size, prev_rec,
 					      index, mtr);
 		prev_rec = insert_rec;
@@ -1944,6 +1953,7 @@ page_cur_delete_rec(
 	page_dir_slot_set_n_owned(cur_dir_slot, page_zip, cur_n_owned - 1);
 
 	/* 6. Free the memory occupied by the record */
+	btr_blob_dbg_remove_rec(current_rec, index, offsets, "delete");
 	page_mem_free(page, page_zip, current_rec, index, offsets);
 
 	/* 7. Now we have decremented the number of owned records of the slot.
diff --git a/storage/innodb_plugin/page/page0page.c b/storage/innodb_plugin/page/page0page.c
index 10008f9ac25..6cae03e8829 100644
--- a/storage/innodb_plugin/page/page0page.c
+++ b/storage/innodb_plugin/page/page0page.c
@@ -685,12 +685,16 @@ page_copy_rec_list_end(
 			if (UNIV_UNLIKELY
 			    (!page_zip_reorganize(new_block, index, mtr))) {
 
+				btr_blob_dbg_remove(new_page, index,
+						    "copy_end_reorg_fail");
 				if (UNIV_UNLIKELY
 				    (!page_zip_decompress(new_page_zip,
 							  new_page, FALSE))) {
 					ut_error;
 				}
 				ut_ad(page_validate(new_page, index));
+				btr_blob_dbg_add(new_page, index,
+						 "copy_end_reorg_fail");
 				return(NULL);
 			} else {
 				/* The page was reorganized:
@@ -803,12 +807,16 @@ page_copy_rec_list_start(
 			if (UNIV_UNLIKELY
 			    (!page_zip_reorganize(new_block, index, mtr))) {
 
+				btr_blob_dbg_remove(new_page, index,
+						    "copy_start_reorg_fail");
 				if (UNIV_UNLIKELY
 				    (!page_zip_decompress(new_page_zip,
 							  new_page, FALSE))) {
 					ut_error;
 				}
 				ut_ad(page_validate(new_page, index));
+				btr_blob_dbg_add(new_page, index,
+						 "copy_start_reorg_fail");
 				return(NULL);
 			} else {
 				/* The page was reorganized:
@@ -1080,6 +1088,9 @@ page_delete_rec_list_end(
 	/* Remove the record chain segment from the record chain */
 	page_rec_set_next(prev_rec, page_get_supremum_rec(page));
 
+	btr_blob_dbg_op(page, rec, index, "delete_end",
+			btr_blob_dbg_remove_rec);
+
 	/* Catenate the deleted chain segment to the page free list */
 
 	page_rec_set_next(last_rec, page_header_get_ptr(page, PAGE_FREE));
diff --git a/storage/innodb_plugin/page/page0zip.c b/storage/innodb_plugin/page/page0zip.c
index d3b1edefc6b..6e866b3f016 100644
--- a/storage/innodb_plugin/page/page0zip.c
+++ b/storage/innodb_plugin/page/page0zip.c
@@ -653,13 +653,13 @@ page_zip_dir_encode(
 Allocate memory for zlib. */
 static
 void*
-page_zip_malloc(
+page_zip_zalloc(
 /*============*/
 	void*	opaque,	/*!< in/out: memory heap */
 	uInt	items,	/*!< in: number of items to allocate */
 	uInt	size)	/*!< in: size of an item in bytes */
 {
-	return(mem_heap_alloc(opaque, items * size));
+	return(mem_heap_zalloc(opaque, items * size));
 }
 
 /**********************************************************************//**
@@ -684,7 +684,7 @@ page_zip_set_alloc(
 {
 	z_stream*	strm = stream;
 
-	strm->zalloc = page_zip_malloc;
+	strm->zalloc = page_zip_zalloc;
 	strm->zfree = page_zip_free;
 	strm->opaque = heap;
 }
@@ -2912,19 +2912,18 @@ zlib_error:
 
 	page_zip_set_alloc(&d_stream, heap);
 
-	if (UNIV_UNLIKELY(inflateInit2(&d_stream, UNIV_PAGE_SIZE_SHIFT)
-			  != Z_OK)) {
-		ut_error;
-	}
-
 	d_stream.next_in = page_zip->data + PAGE_DATA;
 	/* Subtract the space reserved for
 	the page header and the end marker of the modification log. */
 	d_stream.avail_in = page_zip_get_size(page_zip) - (PAGE_DATA + 1);
-
 	d_stream.next_out = page + PAGE_ZIP_START;
 	d_stream.avail_out = UNIV_PAGE_SIZE - PAGE_ZIP_START;
 
+	if (UNIV_UNLIKELY(inflateInit2(&d_stream, UNIV_PAGE_SIZE_SHIFT)
+			  != Z_OK)) {
+		ut_error;
+	}
+
 	/* Decode the zlib header and the index information. */
 	if (UNIV_UNLIKELY(inflate(&d_stream, Z_BLOCK) != Z_OK)) {
 
@@ -4439,7 +4438,7 @@ page_zip_reorganize(
 	log_mode = mtr_set_log_mode(mtr, MTR_LOG_NONE);
 
 #ifndef UNIV_HOTBACKUP
-	temp_block = buf_block_alloc(0);
+	temp_block = buf_block_alloc();
 	btr_search_drop_page_hash_index(block);
 	block->check_index_page_at_flush = TRUE;
 #else /* !UNIV_HOTBACKUP */
@@ -4451,6 +4450,8 @@ page_zip_reorganize(
 	/* Copy the old page to temporary space */
 	buf_frame_copy(temp_page, page);
 
+	btr_blob_dbg_remove(page, index, "zip_reorg");
+
 	/* Recreate the page: note that global data on page (possible
 	segment headers, next page-field, etc.) is preserved intact */
 
@@ -4509,7 +4510,7 @@ page_zip_copy_recs(
 	mtr_t*			mtr)		/*!< in: mini-transaction */
 {
 	ut_ad(mtr_memo_contains_page(mtr, page, MTR_MEMO_PAGE_X_FIX));
-	ut_ad(mtr_memo_contains_page(mtr, (page_t*) src, MTR_MEMO_PAGE_X_FIX));
+	ut_ad(mtr_memo_contains_page(mtr, src, MTR_MEMO_PAGE_X_FIX));
 	ut_ad(!dict_index_is_ibuf(index));
 #ifdef UNIV_ZIP_DEBUG
 	/* The B-tree operations that call this function may set
@@ -4579,6 +4580,7 @@ page_zip_copy_recs(
 #ifdef UNIV_ZIP_DEBUG
 	ut_a(page_zip_validate(page_zip, page));
 #endif /* UNIV_ZIP_DEBUG */
+	btr_blob_dbg_add(page, index, "page_zip_copy_recs");
 
 	page_zip_compress_write_log(page_zip, page, index, mtr);
 }
diff --git a/storage/innodb_plugin/rem/rem0cmp.c b/storage/innodb_plugin/rem/rem0cmp.c
index 35b67992558..04d2c15437b 100644
--- a/storage/innodb_plugin/rem/rem0cmp.c
+++ b/storage/innodb_plugin/rem/rem0cmp.c
@@ -862,6 +862,10 @@ cmp_rec_rec_with_match(
 	const ulint*	offsets1,/*!< in: rec_get_offsets(rec1, index) */
 	const ulint*	offsets2,/*!< in: rec_get_offsets(rec2, index) */
 	dict_index_t*	index,	/*!< in: data dictionary index */
+	ibool		nulls_unequal,
+				/* in: TRUE if this is for index statistics
+				cardinality estimation, and innodb_stats_method
+				is "nulls_unequal" or "nulls_ignored" */
 	ulint*		matched_fields, /*!< in/out: number of already completely
 				matched fields; when the function returns,
 				contains the value the for current
@@ -961,9 +965,13 @@ cmp_rec_rec_with_match(
 			    || rec2_f_len == UNIV_SQL_NULL) {
 
 				if (rec1_f_len == rec2_f_len) {
-
-					goto next_field;
-
+					/* This is limited to stats collection,
+					cannot use it for regular search */
+					if (nulls_unequal) {
+						ret = -1;
+					} else {
+						goto next_field;
+					}
 				} else if (rec2_f_len == UNIV_SQL_NULL) {
 
 					/* We define the SQL null to be the
diff --git a/storage/innodb_plugin/row/row0ins.c b/storage/innodb_plugin/row/row0ins.c
index 298c601c7e3..8050c099751 100644
--- a/storage/innodb_plugin/row/row0ins.c
+++ b/storage/innodb_plugin/row/row0ins.c
@@ -2130,7 +2130,7 @@ function_exit:
 
 		err = btr_store_big_rec_extern_fields(
 			index, btr_cur_get_block(&cursor),
-			rec, offsets, big_rec, &mtr);
+			rec, offsets, &mtr, FALSE, big_rec);
 
 		if (modify) {
 			dtuple_big_rec_free(big_rec);
diff --git a/storage/innodb_plugin/row/row0purge.c b/storage/innodb_plugin/row/row0purge.c
index 8bf2ae0f458..752a2ec9e83 100644
--- a/storage/innodb_plugin/row/row0purge.c
+++ b/storage/innodb_plugin/row/row0purge.c
@@ -387,8 +387,11 @@ Purges an update of an existing record. Also purges an update of a delete
 marked record if that record contained an externally stored field. */
 static
 void
-row_purge_upd_exist_or_extern(
-/*==========================*/
+row_purge_upd_exist_or_extern_func(
+/*===============================*/
+#ifdef UNIV_DEBUG
+	const que_thr_t*thr,	/*!< in: query thread */
+#endif /* UNIV_DEBUG */
 	purge_node_t*	node)	/*!< in: row purge node */
 {
 	mem_heap_t*	heap;
@@ -413,8 +416,8 @@ row_purge_upd_exist_or_extern(
 	while (node->index != NULL) {
 		index = node->index;
 
-		if (row_upd_changes_ord_field_binary(NULL, NULL, node->index,
-						     node->update)) {
+		if (row_upd_changes_ord_field_binary(node->index, node->update,
+						     thr, NULL, NULL)) {
 			/* Build the older version of the index entry */
 			entry = row_build_index_entry(node->row, NULL,
 						      index, heap);
@@ -496,6 +499,14 @@ skip_secondaries:
 	}
 }
 
+#ifdef UNIV_DEBUG
+# define row_purge_upd_exist_or_extern(thr,node)	\
+	row_purge_upd_exist_or_extern_func(thr,node)
+#else /* UNIV_DEBUG */
+# define row_purge_upd_exist_or_extern(thr,node)	\
+	row_purge_upd_exist_or_extern_func(node)
+#endif /* UNIV_DEBUG */
+
 /***********************************************************//**
 Parses the row reference and other info in a modify undo log record.
 @return TRUE if purge operation required: NOTE that then the CALLER
@@ -602,47 +613,32 @@ err_exit:
 /***********************************************************//**
 Fetches an undo log record and does the purge for the recorded operation.
 If none left, or the current purge completed, returns the control to the
-parent node, which is always a query thread node.
-@return	DB_SUCCESS if operation successfully completed, else error code */
-static
-ulint
+parent node, which is always a query thread node. */
+static __attribute__((nonnull))
+void
 row_purge(
 /*======*/
 	purge_node_t*	node,	/*!< in: row purge node */
 	que_thr_t*	thr)	/*!< in: query thread */
 {
-	roll_ptr_t	roll_ptr;
-	ibool		purge_needed;
 	ibool		updated_extern;
-	trx_t*		trx;
 
-	ut_ad(node && thr);
-
-	trx = thr_get_trx(thr);
+	ut_ad(node);
+	ut_ad(thr);
 
-	node->undo_rec = trx_purge_fetch_next_rec(&roll_ptr,
-						  &(node->reservation),
+	node->undo_rec = trx_purge_fetch_next_rec(&node->roll_ptr,
+						  &node->reservation,
 						  node->heap);
 	if (!node->undo_rec) {
 		/* Purge completed for this query thread */
 
 		thr->run_node = que_node_get_parent(node);
 
-		return(DB_SUCCESS);
-	}
-
-	node->roll_ptr = roll_ptr;
-
-	if (node->undo_rec == &trx_purge_dummy_rec) {
-		purge_needed = FALSE;
-	} else {
-		purge_needed = row_purge_parse_undo_rec(node, &updated_extern,
-							thr);
-		/* If purge_needed == TRUE, we must also remember to unfreeze
-		data dictionary! */
+		return;
 	}
 
-	if (purge_needed) {
+	if (node->undo_rec != &trx_purge_dummy_rec
+	    && row_purge_parse_undo_rec(node, &updated_extern, thr)) {
 		node->found_clust = FALSE;
 
 		node->index = dict_table_get_next_index(
@@ -654,14 +650,14 @@ row_purge(
 		} else if (updated_extern
 			   || node->rec_type == TRX_UNDO_UPD_EXIST_REC) {
 
-			row_purge_upd_exist_or_extern(node);
+			row_purge_upd_exist_or_extern(thr, node);
 		}
 
 		if (node->found_clust) {
 			btr_pcur_close(&(node->pcur));
 		}
 
-		row_mysql_unfreeze_data_dictionary(trx);
+		row_mysql_unfreeze_data_dictionary(thr_get_trx(thr));
 	}
 
 	/* Do some cleanup */
@@ -669,8 +665,6 @@ row_purge(
 	mem_heap_empty(node->heap);
 
 	thr->run_node = node;
-
-	return(DB_SUCCESS);
 }
 
 /***********************************************************//**
@@ -684,9 +678,6 @@ row_purge_step(
 	que_thr_t*	thr)	/*!< in: query thread */
 {
 	purge_node_t*	node;
-#ifdef UNIV_DEBUG
-	ulint		err;
-#endif /* UNIV_DEBUG */
 
 	ut_ad(thr);
 
@@ -694,12 +685,7 @@ row_purge_step(
 
 	ut_ad(que_node_get_type(node) == QUE_NODE_PURGE);
 
-#ifdef UNIV_DEBUG
-	err =
-#endif /* UNIV_DEBUG */
 	row_purge(node, thr);
 
-	ut_ad(err == DB_SUCCESS);
-
 	return(thr);
 }
diff --git a/storage/innodb_plugin/row/row0umod.c b/storage/innodb_plugin/row/row0umod.c
index 562f8093c38..5202a498eed 100644
--- a/storage/innodb_plugin/row/row0umod.c
+++ b/storage/innodb_plugin/row/row0umod.c
@@ -173,40 +173,26 @@ row_undo_mod_remove_clust_low(
 	mtr_t*		mtr,	/*!< in: mtr */
 	ulint		mode)	/*!< in: BTR_MODIFY_LEAF or BTR_MODIFY_TREE */
 {
-	btr_pcur_t*	pcur;
 	btr_cur_t*	btr_cur;
 	ulint		err;
-	ibool		success;
 
 	ut_ad(node->rec_type == TRX_UNDO_UPD_DEL_REC);
-	pcur = &(node->pcur);
-	btr_cur = btr_pcur_get_btr_cur(pcur);
 
-	success = btr_pcur_restore_position(mode, pcur, mtr);
+	/* Find out if the record has been purged already
+	or if we can remove it. */
 
-	if (!success) {
+	if (!btr_pcur_restore_position(mode, &node->pcur, mtr)
+	    || row_vers_must_preserve_del_marked(node->new_trx_id, mtr)) {
 
 		return(DB_SUCCESS);
 	}
 
-	/* Find out if we can remove the whole clustered index record */
-
-	if (node->rec_type == TRX_UNDO_UPD_DEL_REC
-	    && !row_vers_must_preserve_del_marked(node->new_trx_id, mtr)) {
-
-		/* Ok, we can remove */
-	} else {
-		return(DB_SUCCESS);
-	}
+	btr_cur = btr_pcur_get_btr_cur(&node->pcur);
 
 	if (mode == BTR_MODIFY_LEAF) {
-		success = btr_cur_optimistic_delete(btr_cur, mtr);
-
-		if (success) {
-			err = DB_SUCCESS;
-		} else {
-			err = DB_FAIL;
-		}
+		err = btr_cur_optimistic_delete(btr_cur, mtr)
+			? DB_SUCCESS
+			: DB_FAIL;
 	} else {
 		ut_ad(mode == BTR_MODIFY_TREE);
 
@@ -668,8 +654,9 @@ row_undo_mod_upd_exist_sec(
 	while (node->index != NULL) {
 		index = node->index;
 
-		if (row_upd_changes_ord_field_binary(
-			    node->row, node->ext, node->index, node->update)) {
+		if (row_upd_changes_ord_field_binary(node->index, node->update,
+						     thr,
+						     node->row, node->ext)) {
 
 			/* Build the newest version of the index entry */
 			entry = row_build_index_entry(node->row, node->ext,
diff --git a/storage/innodb_plugin/row/row0upd.c b/storage/innodb_plugin/row/row0upd.c
index e1c78949603..13134afd1aa 100644
--- a/storage/innodb_plugin/row/row0upd.c
+++ b/storage/innodb_plugin/row/row0upd.c
@@ -498,14 +498,49 @@ row_upd_rec_in_place(
 	n_fields = upd_get_n_fields(update);
 
 	for (i = 0; i < n_fields; i++) {
+#ifdef UNIV_BLOB_DEBUG
+		btr_blob_dbg_t	b;
+		const byte*	field_ref	= NULL;
+#endif /* UNIV_BLOB_DEBUG */
+
 		upd_field = upd_get_nth_field(update, i);
 		new_val = &(upd_field->new_val);
 		ut_ad(!dfield_is_ext(new_val) ==
 		      !rec_offs_nth_extern(offsets, upd_field->field_no));
+#ifdef UNIV_BLOB_DEBUG
+		if (dfield_is_ext(new_val)) {
+			ulint	len;
+			field_ref = rec_get_nth_field(rec, offsets, i, &len);
+			ut_a(len != UNIV_SQL_NULL);
+			ut_a(len >= BTR_EXTERN_FIELD_REF_SIZE);
+			field_ref += len - BTR_EXTERN_FIELD_REF_SIZE;
+
+			b.ref_page_no = page_get_page_no(page_align(rec));
+			b.ref_heap_no = page_rec_get_heap_no(rec);
+			b.ref_field_no = i;
+			b.blob_page_no = mach_read_from_4(
+				field_ref + BTR_EXTERN_PAGE_NO);
+			ut_a(b.ref_field_no >= index->n_uniq);
+			btr_blob_dbg_rbt_delete(index, &b, "upd_in_place");
+		}
+#endif /* UNIV_BLOB_DEBUG */
 
 		rec_set_nth_field(rec, offsets, upd_field->field_no,
 				  dfield_get_data(new_val),
 				  dfield_get_len(new_val));
+
+#ifdef UNIV_BLOB_DEBUG
+		if (dfield_is_ext(new_val)) {
+			b.blob_page_no = mach_read_from_4(
+				field_ref + BTR_EXTERN_PAGE_NO);
+			b.always_owner = b.owner = !(field_ref[BTR_EXTERN_LEN]
+						     & BTR_EXTERN_OWNER_FLAG);
+			b.del = rec_get_deleted_flag(
+				rec, rec_offs_comp(offsets));
+
+			btr_blob_dbg_rbt_insert(index, &b, "upd_in_place");
+		}
+#endif /* UNIV_BLOB_DEBUG */
 	}
 
 	if (UNIV_LIKELY_NULL(page_zip)) {
@@ -1192,25 +1227,31 @@ NOTE: we compare the fields as binary strings!
 @return TRUE if update vector changes an ordering field in the index record */
 UNIV_INTERN
 ibool
-row_upd_changes_ord_field_binary(
-/*=============================*/
+row_upd_changes_ord_field_binary_func(
+/*==================================*/
+	dict_index_t*	index,	/*!< in: index of the record */
+	const upd_t*	update,	/*!< in: update vector for the row; NOTE: the
+				field numbers in this MUST be clustered index
+				positions! */
+#ifdef UNIV_DEBUG
+	const que_thr_t*thr,	/*!< in: query thread */
+#endif /* UNIV_DEBUG */
 	const dtuple_t*	row,	/*!< in: old value of row, or NULL if the
 				row and the data values in update are not
 				known when this function is called, e.g., at
 				compile time */
-	const row_ext_t*ext,	/*!< NULL, or prefixes of the externally
+	const row_ext_t*ext)	/*!< NULL, or prefixes of the externally
 				stored columns in the old row */
-	dict_index_t*	index,	/*!< in: index of the record */
-	const upd_t*	update)	/*!< in: update vector for the row; NOTE: the
-				field numbers in this MUST be clustered index
-				positions! */
 {
 	ulint			n_unique;
 	ulint			i;
 	const dict_index_t*	clust_index;
 
-	ut_ad(update);
 	ut_ad(index);
+	ut_ad(update);
+	ut_ad(thr);
+	ut_ad(thr->graph);
+	ut_ad(thr->graph->trx);
 
 	n_unique = dict_index_get_n_unique(index);
 
@@ -1252,6 +1293,10 @@ row_upd_changes_ord_field_binary(
 		    || dfield_is_null(dfield)) {
 			/* do nothing special */
 		} else if (UNIV_LIKELY_NULL(ext)) {
+			/* Silence a compiler warning without
+			silencing a Valgrind error. */
+			dfield_len = 0;
+			UNIV_MEM_INVALID(&dfield_len, sizeof dfield_len);
 			/* See if the column is stored externally. */
 			buf = row_ext_lookup(ext, col_no, &dfield_len);
 
@@ -1259,9 +1304,14 @@ row_upd_changes_ord_field_binary(
 
 			if (UNIV_LIKELY_NULL(buf)) {
 				if (UNIV_UNLIKELY(buf == field_ref_zero)) {
-					/* This should never happen, but
-					we try to fail safe here. */
-					ut_ad(0);
+					/* The externally stored field
+					was not written yet. This
+					record should only be seen by
+					recv_recovery_rollback_active(),
+					when the server had crashed before
+					storing the field. */
+					ut_ad(thr->graph->trx->is_recovered);
+					ut_ad(trx_is_recv(thr->graph->trx));
 					return(TRUE);
 				}
 
@@ -1608,8 +1658,8 @@ row_upd_sec_step(
 	ut_ad(!dict_index_is_clust(node->index));
 
 	if (node->state == UPD_NODE_UPDATE_ALL_SEC
-	    || row_upd_changes_ord_field_binary(node->row, node->ext,
-						node->index, node->update)) {
+	    || row_upd_changes_ord_field_binary(node->index, node->update,
+						thr, node->row, node->ext)) {
 		return(row_upd_sec_index_entry(node, thr));
 	}
 
@@ -1937,7 +1987,7 @@ row_upd_clust_rec(
 			index, btr_cur_get_block(btr_cur), rec,
 			rec_get_offsets(rec, index, offsets_,
 					ULINT_UNDEFINED, &heap),
-			big_rec, mtr);
+			mtr, TRUE, big_rec);
 		mtr_commit(mtr);
 	}
 
@@ -2136,8 +2186,8 @@ exit_func:
 
 	row_upd_store_row(node);
 
-	if (row_upd_changes_ord_field_binary(node->row, node->ext, index,
-					     node->update)) {
+	if (row_upd_changes_ord_field_binary(index, node->update, thr,
+					     node->row, node->ext)) {
 
 		/* Update causes an ordering field (ordering fields within
 		the B-tree) of the clustered index record to change: perform
diff --git a/storage/innodb_plugin/row/row0vers.c b/storage/innodb_plugin/row/row0vers.c
index b6d35363f08..d4fde0b939b 100644
--- a/storage/innodb_plugin/row/row0vers.c
+++ b/storage/innodb_plugin/row/row0vers.c
@@ -669,11 +669,15 @@ row_vers_build_for_semi_consistent_read(
 
 		mutex_enter(&kernel_mutex);
 		version_trx = trx_get_on_id(version_trx_id);
+		if (version_trx
+		    && (version_trx->conc_state == TRX_COMMITTED_IN_MEMORY
+			|| version_trx->conc_state == TRX_NOT_STARTED)) {
+
+			version_trx = NULL;
+		}
 		mutex_exit(&kernel_mutex);
 
-		if (!version_trx
-		    || version_trx->conc_state == TRX_NOT_STARTED
-		    || version_trx->conc_state == TRX_COMMITTED_IN_MEMORY) {
+		if (!version_trx) {
 
 			/* We found a version that belongs to a
 			committed transaction: return it. */
diff --git a/storage/innodb_plugin/srv/srv0srv.c b/storage/innodb_plugin/srv/srv0srv.c
index f7e7e351bdc..b1fc1ac67fd 100644
--- a/storage/innodb_plugin/srv/srv0srv.c
+++ b/storage/innodb_plugin/srv/srv0srv.c
@@ -243,6 +243,11 @@ UNIV_INTERN ulong	srv_max_buf_pool_modified_pct	= 75;
 /* variable counts amount of data read in total (in bytes) */
 UNIV_INTERN ulint srv_data_read = 0;
 
+/* Internal setting for "innodb_stats_method". Decides how InnoDB treats
+NULL value when collecting statistics. By default, it is set to
+SRV_STATS_NULLS_EQUAL(0), ie. all NULL value are treated equal */
+ulong srv_innodb_stats_method = SRV_STATS_NULLS_EQUAL;
+
 /* here we count the amount of data written in total (in bytes) */
 UNIV_INTERN ulint srv_data_written = 0;
 
@@ -2231,6 +2236,12 @@ srv_error_monitor_thread(
 	ulint		fatal_cnt	= 0;
 	ib_uint64_t	old_lsn;
 	ib_uint64_t	new_lsn;
+	/* longest waiting thread for a semaphore */
+	os_thread_id_t	waiter		= os_thread_get_curr_id();
+	os_thread_id_t	old_waiter	= waiter;
+	/* the semaphore that is being waited for */
+	const void*	sema		= NULL;
+	const void*	old_sema	= NULL;
 
 	old_lsn = srv_start_lsn;
 
@@ -2279,7 +2290,8 @@ loop:
 
 	sync_arr_wake_threads_if_sema_free();
 
-	if (sync_array_print_long_waits()) {
+	if (sync_array_print_long_waits(&waiter, &sema)
+	    && sema == old_sema && os_thread_eq(waiter, old_waiter)) {
 		fatal_cnt++;
 		if (fatal_cnt > 10) {
 
@@ -2294,6 +2306,8 @@ loop:
 		}
 	} else {
 		fatal_cnt = 0;
+		old_waiter = waiter;
+		old_sema = sema;
 	}
 
 	/* Flush stderr so that a database user gets the output
diff --git a/storage/innodb_plugin/srv/srv0start.c b/storage/innodb_plugin/srv/srv0start.c
index 73f8f319704..f8b5049ca65 100644
--- a/storage/innodb_plugin/srv/srv0start.c
+++ b/storage/innodb_plugin/srv/srv0start.c
@@ -1061,6 +1061,12 @@ innobase_start_or_create_for_mysql(void)
 		);
 #endif
 
+#ifdef UNIV_BLOB_DEBUG
+	fprintf(stderr,
+		"InnoDB: !!!!!!!! UNIV_BLOB_DEBUG switched on !!!!!!!!!\n"
+		"InnoDB: Server restart may fail with UNIV_BLOB_DEBUG\n");
+#endif /* UNIV_BLOB_DEBUG */
+
 #ifdef UNIV_SYNC_DEBUG
 	fprintf(stderr,
 		"InnoDB: !!!!!!!! UNIV_SYNC_DEBUG switched on !!!!!!!!!\n");
diff --git a/storage/innodb_plugin/sync/sync0arr.c b/storage/innodb_plugin/sync/sync0arr.c
index 3c825e2202b..13970023573 100644
--- a/storage/innodb_plugin/sync/sync0arr.c
+++ b/storage/innodb_plugin/sync/sync0arr.c
@@ -1,6 +1,6 @@
 /*****************************************************************************
 
-Copyright (c) 1995, 2009, Innobase Oy. All Rights Reserved.
+Copyright (c) 1995, 2011, Oracle and/or its affiliates. All Rights Reserved.
 Copyright (c) 2008, Google Inc.
 
 Portions of this file contain modifications contributed and copyrighted by
@@ -715,7 +715,7 @@ print:
 					fprintf(stderr, "rw-lock %p ",
 						(void*) lock);
 					sync_array_cell_print(stderr, cell);
-					rw_lock_debug_print(debug);
+					rw_lock_debug_print(stderr, debug);
 					return(TRUE);
 				}
 			}
@@ -914,8 +914,10 @@ Prints warnings of long semaphore waits to stderr.
 @return	TRUE if fatal semaphore wait threshold was exceeded */
 UNIV_INTERN
 ibool
-sync_array_print_long_waits(void)
-/*=============================*/
+sync_array_print_long_waits(
+/*========================*/
+	os_thread_id_t*	waiter,	/*!< out: longest waiting thread */
+	const void**	sema)	/*!< out: longest-waited-for semaphore */
 {
 	sync_cell_t*	cell;
 	ibool		old_val;
@@ -923,24 +925,40 @@ sync_array_print_long_waits(void)
 	ulint		i;
 	ulint		fatal_timeout = srv_fatal_semaphore_wait_threshold;
 	ibool		fatal = FALSE;
+	double		longest_diff = 0;
 
 	for (i = 0; i < sync_primary_wait_array->n_cells; i++) {
 
+		double	diff;
+		void*	wait_object;
+
 		cell = sync_array_get_nth_cell(sync_primary_wait_array, i);
 
-		if (cell->wait_object != NULL && cell->waiting
-		    && difftime(time(NULL), cell->reservation_time) > 240) {
+		wait_object = cell->wait_object;
+
+		if (wait_object == NULL || !cell->waiting) {
+
+			continue;
+		}
+
+		diff = difftime(time(NULL), cell->reservation_time);
+
+		if (diff > 240) {
 			fputs("InnoDB: Warning: a long semaphore wait:\n",
 			      stderr);
 			sync_array_cell_print(stderr, cell);
 			noticed = TRUE;
 		}
 
-		if (cell->wait_object != NULL && cell->waiting
-		    && difftime(time(NULL), cell->reservation_time)
-		    > fatal_timeout) {
+		if (diff > fatal_timeout) {
 			fatal = TRUE;
 		}
+
+		if (diff > longest_diff) {
+			longest_diff = diff;
+			*sema = wait_object;
+			*waiter = cell->thread;
+		}
 	}
 
 	if (noticed) {
diff --git a/storage/innodb_plugin/sync/sync0rw.c b/storage/innodb_plugin/sync/sync0rw.c
index 572c3690a7f..a5da606ad80 100644
--- a/storage/innodb_plugin/sync/sync0rw.c
+++ b/storage/innodb_plugin/sync/sync0rw.c
@@ -1,6 +1,6 @@
 /*****************************************************************************
 
-Copyright (c) 1995, 2009, Innobase Oy. All Rights Reserved.
+Copyright (c) 1995, 2011, Oracle and/or its affiliates. All Rights Reserved.
 Copyright (c) 2008, Google Inc.
 
 Portions of this file contain modifications contributed and copyrighted by
@@ -260,6 +260,9 @@ rw_lock_create_func(
 	contains garbage at initialization and cannot be used for
 	recursive x-locking. */
 	lock->recursive = FALSE;
+	/* Silence Valgrind when UNIV_DEBUG_VALGRIND is not enabled. */
+	memset((void*) &lock->writer_thread, 0, sizeof lock->writer_thread);
+	UNIV_MEM_INVALID(&lock->writer_thread, sizeof lock->writer_thread);
 
 #ifdef UNIV_SYNC_DEBUG
 	UT_LIST_INIT(lock->debug_list);
@@ -925,7 +928,7 @@ rw_lock_list_print_info(
 
 			info = UT_LIST_GET_FIRST(lock->debug_list);
 			while (info != NULL) {
-				rw_lock_debug_print(info);
+				rw_lock_debug_print(file, info);
 				info = UT_LIST_GET_NEXT(list, info);
 			}
 		}
@@ -973,7 +976,7 @@ rw_lock_print(
 
 		info = UT_LIST_GET_FIRST(lock->debug_list);
 		while (info != NULL) {
-			rw_lock_debug_print(info);
+			rw_lock_debug_print(stderr, info);
 			info = UT_LIST_GET_NEXT(list, info);
 		}
 	}
@@ -985,28 +988,29 @@ UNIV_INTERN
 void
 rw_lock_debug_print(
 /*================*/
+	FILE*			f,	/*!< in: output stream */
 	rw_lock_debug_t*	info)	/*!< in: debug struct */
 {
 	ulint	rwt;
 
 	rwt	  = info->lock_type;
 
-	fprintf(stderr, "Locked: thread %lu file %s line %lu  ",
+	fprintf(f, "Locked: thread %lu file %s line %lu  ",
 		(ulong) os_thread_pf(info->thread_id), info->file_name,
 		(ulong) info->line);
 	if (rwt == RW_LOCK_SHARED) {
-		fputs("S-LOCK", stderr);
+		fputs("S-LOCK", f);
 	} else if (rwt == RW_LOCK_EX) {
-		fputs("X-LOCK", stderr);
+		fputs("X-LOCK", f);
 	} else if (rwt == RW_LOCK_WAIT_EX) {
-		fputs("WAIT X-LOCK", stderr);
+		fputs("WAIT X-LOCK", f);
 	} else {
 		ut_error;
 	}
 	if (info->pass != 0) {
-		fprintf(stderr, " pass value %lu", (ulong) info->pass);
+		fprintf(f, " pass value %lu", (ulong) info->pass);
 	}
-	putc('\n', stderr);
+	putc('\n', f);
 }
 
 /***************************************************************//**
diff --git a/storage/innodb_plugin/trx/trx0i_s.c b/storage/innodb_plugin/trx/trx0i_s.c
index e148234888b..5cc9df2d5c4 100644
--- a/storage/innodb_plugin/trx/trx0i_s.c
+++ b/storage/innodb_plugin/trx/trx0i_s.c
@@ -504,7 +504,7 @@ fill_trx_row(
 		query[stmt_len] = '\0';
 
 		row->trx_query = ha_storage_put_memlim(
-			cache->storage, stmt, stmt_len + 1,
+			cache->storage, query, stmt_len + 1,
 			MAX_ALLOWED_FOR_STORAGE(cache));
 
 		row->trx_query_cs = innobase_get_charset(trx->mysql_thd);
diff --git a/storage/innodb_plugin/trx/trx0roll.c b/storage/innodb_plugin/trx/trx0roll.c
index 1a43e419214..a4bbf7fd652 100644
--- a/storage/innodb_plugin/trx/trx0roll.c
+++ b/storage/innodb_plugin/trx/trx0roll.c
@@ -48,8 +48,8 @@ Created 3/26/1996 Heikki Tuuri
 rollback */
 #define TRX_ROLL_TRUNC_THRESHOLD	1
 
-/** In crash recovery, the current trx to be rolled back */
-static trx_t*		trx_roll_crash_recv_trx	= NULL;
+/** In crash recovery, the current trx to be rolled back; NULL otherwise */
+static const trx_t*	trx_roll_crash_recv_trx	= NULL;
 
 /** In crash recovery we set this to the undo n:o of the current trx to be
 rolled back. Then we can print how many % the rollback has progressed. */
diff --git a/storage/innodb_plugin/trx/trx0trx.c b/storage/innodb_plugin/trx/trx0trx.c
index ee744fd58b1..f0bbf220815 100644
--- a/storage/innodb_plugin/trx/trx0trx.c
+++ b/storage/innodb_plugin/trx/trx0trx.c
@@ -2010,18 +2010,18 @@ trx_recover_for_mysql(
 /*******************************************************************//**
 This function is used to find one X/Open XA distributed transaction
 which is in the prepared state
-@return	trx or NULL */
+@return	trx or NULL; on match, the trx->xid will be invalidated */
 UNIV_INTERN
 trx_t*
 trx_get_trx_by_xid(
 /*===============*/
-	XID*	xid)	/*!< in: X/Open XA transaction identification */
+	const XID*	xid)	/*!< in: X/Open XA transaction identifier */
 {
 	trx_t*	trx;
 
 	if (xid == NULL) {
 
-		return (NULL);
+		return(NULL);
 	}
 
 	mutex_enter(&kernel_mutex);
@@ -2034,10 +2034,16 @@ trx_get_trx_by_xid(
 		of gtrid_lenght+bqual_length bytes should be
 		the same */
 
-		if (xid->gtrid_length == trx->xid.gtrid_length
+		if (trx->conc_state == TRX_PREPARED
+		    && xid->gtrid_length == trx->xid.gtrid_length
 		    && xid->bqual_length == trx->xid.bqual_length
 		    && memcmp(xid->data, trx->xid.data,
 			      xid->gtrid_length + xid->bqual_length) == 0) {
+
+			/* Invalidate the XID, so that subsequent calls
+			will not find it. */
+			memset(&trx->xid, 0, sizeof(trx->xid));
+			trx->xid.formatID = -1;
 			break;
 		}
 
@@ -2046,14 +2052,5 @@ trx_get_trx_by_xid(
 
 	mutex_exit(&kernel_mutex);
 
-	if (trx) {
-		if (trx->conc_state != TRX_PREPARED) {
-
-			return(NULL);
-		}
-
-		return(trx);
-	} else {
-		return(NULL);
-	}
+	return(trx);
 }
diff --git a/storage/maria/ha_maria.cc b/storage/maria/ha_maria.cc
index 8da234111b2..5661e1f06d7 100644
--- a/storage/maria/ha_maria.cc
+++ b/storage/maria/ha_maria.cc
@@ -789,9 +789,10 @@ can_enable_indexes(1), bulk_insert_single_undo(BULK_INSERT_NONE)
 {}
 
 
-handler *ha_maria::clone(MEM_ROOT *mem_root)
+handler *ha_maria::clone(const char *name, MEM_ROOT *mem_root)
 {
-  ha_maria *new_handler= static_cast <ha_maria *>(handler::clone(mem_root));
+  ha_maria *new_handler= static_cast <ha_maria *>(handler::clone(name,
+                                                                 mem_root));
   if (new_handler)
   {
     new_handler->file->state= file->state;
diff --git a/storage/maria/ha_maria.h b/storage/maria/ha_maria.h
index 6ca1f6ca797..6171f89cb18 100644
--- a/storage/maria/ha_maria.h
+++ b/storage/maria/ha_maria.h
@@ -51,7 +51,7 @@ class ha_maria :public handler
 public:
   ha_maria(handlerton *hton, TABLE_SHARE * table_arg);
   ~ha_maria() {}
-  handler *clone(MEM_ROOT *mem_root);
+  handler *clone(const char *name, MEM_ROOT *mem_root);
   const char *table_type() const
   { return "MARIA"; }
   const char *index_type(uint key_number);
diff --git a/storage/maria/ma_init.c b/storage/maria/ma_init.c
index 9e5b600c972..8f695acfe5a 100644
--- a/storage/maria/ma_init.c
+++ b/storage/maria/ma_init.c
@@ -21,6 +21,7 @@
 #include "trnman_public.h"
 #include "ma_checkpoint.h"
 #include <hash.h>
+#include <my_handler.h>
 
 void history_state_free(MARIA_STATE_HISTORY_CLOSED *closed_history)
 {
diff --git a/storage/myisam/ft_stopwords.c b/storage/myisam/ft_stopwords.c
index 05948a936a6..5bfbf7e6c61 100644
--- a/storage/myisam/ft_stopwords.c
+++ b/storage/myisam/ft_stopwords.c
@@ -16,7 +16,7 @@
 /* Written by Sergei A. Golubchik, who has a shared copyright to this code */
 
 #include "ftdefs.h"
-#include "my_handler.h"
+#include "my_compare.h"
 
 typedef struct st_ft_stopwords
 {
diff --git a/storage/myisam/ha_myisam.cc b/storage/myisam/ha_myisam.cc
index f8f9340ba3a..f736a99df42 100644
--- a/storage/myisam/ha_myisam.cc
+++ b/storage/myisam/ha_myisam.cc
@@ -20,12 +20,8 @@
 
 #define MYSQL_SERVER 1
 #include "mysql_priv.h"
-#include <mysql/plugin.h>
-#include <m_ctype.h>
 #include <my_bit.h>
-#include <myisampack.h>
 #include "ha_myisam.h"
-#include <stdarg.h>
 #include "myisamdef.h"
 #include "rt_index.h"
 
@@ -552,9 +548,10 @@ ha_myisam::ha_myisam(handlerton *hton, TABLE_SHARE *table_arg)
    can_enable_indexes(1)
 {}
 
-handler *ha_myisam::clone(MEM_ROOT *mem_root)
+handler *ha_myisam::clone(const char *name, MEM_ROOT *mem_root)
 {
-  ha_myisam *new_handler= static_cast <ha_myisam *>(handler::clone(mem_root));
+  ha_myisam *new_handler= static_cast <ha_myisam *>(handler::clone(name,
+                                                                   mem_root));
   if (new_handler)
     new_handler->file->state= file->state;
   return new_handler;
diff --git a/storage/myisam/ha_myisam.h b/storage/myisam/ha_myisam.h
index 0e53bc58c81..7ca9c191bdf 100644
--- a/storage/myisam/ha_myisam.h
+++ b/storage/myisam/ha_myisam.h
@@ -21,7 +21,6 @@
 /* class for the the myisam handler */
 
 #include <myisam.h>
-#include <myisamchk.h>
 #include <ft_global.h>
 
 #define HA_RECOVER_NONE		0	/* No automatic recover */
@@ -46,7 +45,7 @@ class ha_myisam: public handler
  public:
   ha_myisam(handlerton *hton, TABLE_SHARE *table_arg);
   ~ha_myisam() {}
-  handler *clone(MEM_ROOT *mem_root);
+  handler *clone(const char *name, MEM_ROOT *mem_root);
   const char *table_type() const { return "MyISAM"; }
   const char *index_type(uint key_number);
   const char **bas_ext() const;
diff --git a/storage/myisam/mi_create.c b/storage/myisam/mi_create.c
index d5ce941bf75..f40f1bad710 100644
--- a/storage/myisam/mi_create.c
+++ b/storage/myisam/mi_create.c
@@ -848,8 +848,8 @@ int mi_create(const char *name,uint keys,MI_KEYDEF *keydefs,
 
 err:
   pthread_mutex_unlock(&THR_LOCK_myisam);
-err_no_lock:
 
+err_no_lock:
   save_errno=my_errno;
   switch (errpos) {
   case 3:
diff --git a/storage/myisam/mi_test1.c b/storage/myisam/mi_test1.c
index a6e870f3cde..199334e8b1b 100644
--- a/storage/myisam/mi_test1.c
+++ b/storage/myisam/mi_test1.c
@@ -16,6 +16,7 @@
 /* Testing of the basic functions of a MyISAM table */
 
 #include "myisam.h"
+#include "myisamdef.h"
 #include <my_getopt.h>
 #include <m_string.h>
 
diff --git a/storage/myisam/mi_write.c b/storage/myisam/mi_write.c
index 86c4df77817..8229dfef9a5 100644
--- a/storage/myisam/mi_write.c
+++ b/storage/myisam/mi_write.c
@@ -17,6 +17,7 @@
 
 #include "fulltext.h"
 #include "rt_index.h"
+#include "my_compare.h"
 
 #define MAX_POINTER_LENGTH 8
 
diff --git a/storage/myisam/myisamdef.h b/storage/myisam/myisamdef.h
index e03f88b1a1f..ee782cf2ab0 100644
--- a/storage/myisam/myisamdef.h
+++ b/storage/myisam/myisamdef.h
@@ -15,8 +15,8 @@
 
 /* This file is included by all internal myisam files */
 
-#include "myisam.h"                     /* Structs & some defines */
-#include "myisampack.h"                 /* packing of keys */
+#include <myisam.h>                     /* Structs & some defines */
+#include <myisampack.h>                 /* packing of keys */
 #include <my_tree.h>
 #ifdef THREAD
 #include <my_pthread.h>
diff --git a/storage/myisam/sp_test.c b/storage/myisam/sp_test.c
index f572c7ab19b..7a30a742fd6 100644
--- a/storage/myisam/sp_test.c
+++ b/storage/myisam/sp_test.c
@@ -17,6 +17,7 @@
 /* Written by Alex Barkov, who has a shared copyright to this code */
 
 #include "myisam.h"
+#include "myisamdef.h"
 
 #ifdef HAVE_SPATIAL
 #include "sp_defs.h"
diff --git a/storage/myisammrg/ha_myisammrg.cc b/storage/myisammrg/ha_myisammrg.cc
index 99513e2267f..e6fd3ed4939 100644
--- a/storage/myisammrg/ha_myisammrg.cc
+++ b/storage/myisammrg/ha_myisammrg.cc
@@ -459,8 +459,7 @@ int ha_myisammrg::open(const char *name, int mode __attribute__((unused)),
       problem because all locking is handled by the original MERGE table
       from which this is cloned of.
     */
-    if (!(file= myrg_open(table->s->normalized_path.str, table->db_stat, 
-                                       HA_OPEN_IGNORE_IF_LOCKED)))
+    if (!(file= myrg_open(name, table->db_stat, HA_OPEN_IGNORE_IF_LOCKED)))
     {
       DBUG_PRINT("error", ("my_errno %d", my_errno));
       DBUG_RETURN(my_errno ? my_errno : -1); 
@@ -484,7 +483,7 @@ int ha_myisammrg::open(const char *name, int mode __attribute__((unused)),
 
    @return A cloned handler instance.
  */
-handler *ha_myisammrg::clone(MEM_ROOT *mem_root)
+handler *ha_myisammrg::clone(const char *name, MEM_ROOT *mem_root)
 {
   MYRG_TABLE    *u_table,*newu_table;
   ha_myisammrg *new_handler= 
@@ -505,8 +504,8 @@ handler *ha_myisammrg::clone(MEM_ROOT *mem_root)
     return NULL;
   }
 
-  if (new_handler->ha_open(table, table->s->normalized_path.str, table->db_stat,
-                            HA_OPEN_IGNORE_IF_LOCKED))
+  if (new_handler->ha_open(table, name, table->db_stat,
+                           HA_OPEN_IGNORE_IF_LOCKED))
   {
     delete new_handler;
     return NULL;
diff --git a/storage/myisammrg/ha_myisammrg.h b/storage/myisammrg/ha_myisammrg.h
index 4a65a60d97b..aa8f8d3e2be 100644
--- a/storage/myisammrg/ha_myisammrg.h
+++ b/storage/myisammrg/ha_myisammrg.h
@@ -62,7 +62,7 @@ class ha_myisammrg: public handler
   int open(const char *name, int mode, uint test_if_locked);
   int attach_children(void);
   int detach_children(void);
-  virtual handler *clone(MEM_ROOT *mem_root);
+  virtual handler *clone(const char *name, MEM_ROOT *mem_root);
   int close(void);
   int write_row(uchar * buf);
   int update_row(const uchar * old_data, uchar * new_data);