buf0buf.c, buf0buf.ic, buf0buf.h:

  Reduce memory usage of the buffer headers
Many files:
  Merge InnoDB-4.1 with AWE support


sql/mysqld.cc:
  Merge InnoDB-4.1 with AWE support
sql/set_var.cc:
  Merge InnoDB-4.1 with AWE support
sql/ha_innodb.h:
  Merge InnoDB-4.1 with AWE support
sql/ha_innodb.cc:
  Merge InnoDB-4.1 with AWE support
innobase/btr/btr0cur.c:
  Merge InnoDB-4.1 with AWE support
innobase/btr/btr0pcur.c:
  Merge InnoDB-4.1 with AWE support
innobase/buf/buf0flu.c:
  Merge InnoDB-4.1 with AWE support
innobase/buf/buf0lru.c:
  Merge InnoDB-4.1 with AWE support
innobase/buf/buf0rea.c:
  Merge InnoDB-4.1 with AWE support
innobase/include/btr0pcur.h:
  Merge InnoDB-4.1 with AWE support
innobase/include/buf0lru.h:
  Merge InnoDB-4.1 with AWE support
innobase/include/log0recv.h:
  Merge InnoDB-4.1 with AWE support
innobase/include/os0proc.h:
  Merge InnoDB-4.1 with AWE support
innobase/include/srv0srv.h:
  Merge InnoDB-4.1 with AWE support
innobase/log/log0log.c:
  Merge InnoDB-4.1 with AWE support
innobase/log/log0recv.c:
  Merge InnoDB-4.1 with AWE support
innobase/os/os0file.c:
  Merge InnoDB-4.1 with AWE support
innobase/os/os0proc.c:
  Merge InnoDB-4.1 with AWE support
innobase/srv/srv0srv.c:
  Merge InnoDB-4.1 with AWE support
innobase/srv/srv0start.c:
  Merge InnoDB-4.1 with AWE support
innobase/trx/trx0sys.c:
  Merge InnoDB-4.1 with AWE support
innobase/trx/trx0trx.c:
  Merge InnoDB-4.1 with AWE support
innobase/ut/ut0ut.c:
  Merge InnoDB-4.1 with AWE support
innobase/include/buf0buf.h:
  Reduce memory usage of the buffer headers
innobase/include/buf0buf.ic:
  Reduce memory usage of the buffer headers
innobase/buf/buf0buf.c:
  Reduce memory usage of the buffer headers

2 files changed, 37 insertions, 12 deletions

diff --git a/innobase/btr/btr0cur.c b/innobase/btr/btr0cur.c
index 24f0447d55d..e1d12c9adc4 100644
--- a/innobase/btr/btr0cur.c
+++ b/innobase/btr/btr0cur.c
@@ -291,6 +291,7 @@ btr_cur_search_to_nth_level(
 		&& latch_mode <= BTR_MODIFY_LEAF && info->last_hash_succ
 		&& !estimate
 		&& mode != PAGE_CUR_LE_OR_EXTENDS
+		&& srv_use_adaptive_hash_indexes
 	        && btr_search_guess_on_hash(index, info, tuple, mode,
 						latch_mode, cursor,
 						has_search_latch, mtr)) {
@@ -495,9 +496,11 @@ retry_page_get:
 		cursor->up_bytes = up_bytes;
 
 #ifdef BTR_CUR_ADAPT		
-		btr_search_info_update(index, cursor);
-#endif
+		if (srv_use_adaptive_hash_indexes) {
 
+			btr_search_info_update(index, cursor);
+		}
+#endif
 		ut_ad(cursor->up_match != ULINT_UNDEFINED
 						|| mode != PAGE_CUR_GE);
 		ut_ad(cursor->up_match != ULINT_UNDEFINED
diff --git a/innobase/btr/btr0pcur.c b/innobase/btr/btr0pcur.c
index b2115dfdd6c..13efacb9da3 100644
--- a/innobase/btr/btr0pcur.c
+++ b/innobase/btr/btr0pcur.c
@@ -95,7 +95,9 @@ btr_pcur_store_position(
 	ut_a(cursor->latch_mode != BTR_NO_LATCHES);
 
 	if (page_get_n_recs(page) == 0) {
-		/* It must be an empty index tree */
+		/* It must be an empty index tree; NOTE that in this case
+		we do not store the modify_clock, but always do a search
+		if we restore the cursor position */
 
 		ut_a(btr_page_get_next(page, mtr) == FIL_NULL
 		     && btr_page_get_prev(page, mtr) == FIL_NULL);
@@ -128,12 +130,13 @@ btr_pcur_store_position(
 	} else {
 		cursor->rel_pos = BTR_PCUR_ON;
 	}
-	
+
 	cursor->old_stored = BTR_PCUR_OLD_STORED;
 	cursor->old_rec = dict_tree_copy_rec_order_prefix(tree, rec,
 						&(cursor->old_rec_buf),
 						&(cursor->buf_size));
 									
+	cursor->block_when_stored = buf_block_align(page);	
 	cursor->modify_clock = buf_frame_get_modify_clock(page);
 }
 
@@ -205,6 +208,9 @@ btr_pcur_restore_position(
 	if (cursor->rel_pos == BTR_PCUR_AFTER_LAST_IN_TREE
 	    || cursor->rel_pos == BTR_PCUR_BEFORE_FIRST_IN_TREE) {
 
+	    	/* In these cases we do not try an optimistic restoration,
+	    	but always do a search */
+
 	    	if (cursor->rel_pos == BTR_PCUR_BEFORE_FIRST_IN_TREE) {
 	    		from_left = TRUE;
 	    	} else {
@@ -214,6 +220,10 @@ btr_pcur_restore_position(
 		btr_cur_open_at_index_side(from_left,
 			btr_pcur_get_btr_cur(cursor)->index, latch_mode,
 					btr_pcur_get_btr_cur(cursor), mtr);
+
+		cursor->block_when_stored =
+				buf_block_align(btr_pcur_get_page(cursor));
+
 		return(FALSE);
 	}
 	
@@ -224,8 +234,9 @@ btr_pcur_restore_position(
 	if (latch_mode == BTR_SEARCH_LEAF || latch_mode == BTR_MODIFY_LEAF) {
 		/* Try optimistic restoration */
 	    
-		if (buf_page_optimistic_get(latch_mode, page,
-						cursor->modify_clock, mtr)) {
+		if (buf_page_optimistic_get(latch_mode,
+					    cursor->block_when_stored, page,
+					    cursor->modify_clock, mtr)) {
 			cursor->pos_state = BTR_PCUR_IS_POSITIONED;
 
 			buf_page_dbg_add_level(page, SYNC_TREE_NODE);
@@ -270,8 +281,6 @@ btr_pcur_restore_position(
 
 	btr_pcur_open_with_no_init(btr_pcur_get_btr_cur(cursor)->index, tuple,
 					mode, latch_mode, cursor, 0, mtr);
-
-	cursor->old_stored = BTR_PCUR_OLD_STORED;
 	
 	/* Restore the old search mode */
 	cursor->search_mode = old_mode;
@@ -280,11 +289,18 @@ btr_pcur_restore_position(
 	    && btr_pcur_is_on_user_rec(cursor, mtr)
 	    && 0 == cmp_dtuple_rec(tuple, btr_pcur_get_rec(cursor))) {
 
-	        /* We have to store the NEW value for the modify clock, since
-	        the cursor can now be on a different page! */
+		/* We have to store the NEW value for the modify clock, since
+		the cursor can now be on a different page! But we can retain
+		the value of old_rec */
+
+		cursor->modify_clock =
+			buf_frame_get_modify_clock(btr_pcur_get_page(cursor));
+
+		cursor->block_when_stored =
+			buf_block_align(btr_pcur_get_page(cursor));
+
+		cursor->old_stored = BTR_PCUR_OLD_STORED;
 
-	        cursor->modify_clock = buf_frame_get_modify_clock(
-				    buf_frame_align(btr_pcur_get_rec(cursor)));
 		mem_heap_free(heap);
 
 		return(TRUE);
@@ -292,6 +308,12 @@ btr_pcur_restore_position(
 
 	mem_heap_free(heap);
 
+	/* We have to store new position information, modify_clock etc.,
+	to the cursor because it can now be on a different page, the record
+	under it may have been removed, etc. */
+	
+	btr_pcur_store_position(cursor, mtr);
+
 	return(FALSE);
 }