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diff --git a/storage/innobase/ibuf/ibuf0ibuf.cc b/storage/innobase/ibuf/ibuf0ibuf.cc
new file mode 100644
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--- /dev/null
+++ b/storage/innobase/ibuf/ibuf0ibuf.cc
@@ -0,0 +1,5223 @@
+/*****************************************************************************
+
+Copyright (c) 1997, 2014, Oracle and/or its affiliates. All Rights Reserved.
+
+This program is free software; you can redistribute it and/or modify it under
+the terms of the GNU General Public License as published by the Free Software
+Foundation; version 2 of the License.
+
+This program is distributed in the hope that it will be useful, but WITHOUT
+ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License along with
+this program; if not, write to the Free Software Foundation, Inc.,
+51 Franklin Street, Suite 500, Boston, MA 02110-1335 USA
+
+*****************************************************************************/
+
+/**************************************************//**
+@file ibuf/ibuf0ibuf.cc
+Insert buffer
+
+Created 7/19/1997 Heikki Tuuri
+*******************************************************/
+
+#include "ibuf0ibuf.h"
+
+#if defined UNIV_DEBUG || defined UNIV_IBUF_DEBUG
+UNIV_INTERN my_bool	srv_ibuf_disable_background_merge;
+#endif /* UNIV_DEBUG || UNIV_IBUF_DEBUG */
+
+/** Number of bits describing a single page */
+#define IBUF_BITS_PER_PAGE	4
+#if IBUF_BITS_PER_PAGE % 2
+# error "IBUF_BITS_PER_PAGE must be an even number!"
+#endif
+/** The start address for an insert buffer bitmap page bitmap */
+#define IBUF_BITMAP		PAGE_DATA
+
+#ifdef UNIV_NONINL
+#include "ibuf0ibuf.ic"
+#endif
+
+#ifndef UNIV_HOTBACKUP
+
+#include "buf0buf.h"
+#include "buf0rea.h"
+#include "fsp0fsp.h"
+#include "trx0sys.h"
+#include "fil0fil.h"
+#include "rem0rec.h"
+#include "btr0cur.h"
+#include "btr0pcur.h"
+#include "btr0btr.h"
+#include "row0upd.h"
+#include "sync0sync.h"
+#include "dict0boot.h"
+#include "fut0lst.h"
+#include "lock0lock.h"
+#include "log0recv.h"
+#include "que0que.h"
+#include "srv0start.h" /* srv_shutdown_state */
+#include "ha_prototypes.h"
+#include "rem0cmp.h"
+
+/*	STRUCTURE OF AN INSERT BUFFER RECORD
+
+In versions < 4.1.x:
+
+1. The first field is the page number.
+2. The second field is an array which stores type info for each subsequent
+   field. We store the information which affects the ordering of records, and
+   also the physical storage size of an SQL NULL value. E.g., for CHAR(10) it
+   is 10 bytes.
+3. Next we have the fields of the actual index record.
+
+In versions >= 4.1.x:
+
+Note that contary to what we planned in the 1990's, there will only be one
+insert buffer tree, and that is in the system tablespace of InnoDB.
+
+1. The first field is the space id.
+2. The second field is a one-byte marker (0) which differentiates records from
+   the < 4.1.x storage format.
+3. The third field is the page number.
+4. The fourth field contains the type info, where we have also added 2 bytes to
+   store the charset. In the compressed table format of 5.0.x we must add more
+   information here so that we can build a dummy 'index' struct which 5.0.x
+   can use in the binary search on the index page in the ibuf merge phase.
+5. The rest of the fields contain the fields of the actual index record.
+
+In versions >= 5.0.3:
+
+The first byte of the fourth field is an additional marker (0) if the record
+is in the compact format.  The presence of this marker can be detected by
+looking at the length of the field modulo DATA_NEW_ORDER_NULL_TYPE_BUF_SIZE.
+
+The high-order bit of the character set field in the type info is the
+"nullable" flag for the field.
+
+In versions >= 5.5:
+
+The optional marker byte at the start of the fourth field is replaced by
+mandatory 3 fields, totaling 4 bytes:
+
+ 1. 2 bytes: Counter field, used to sort records within a (space id, page
+    no) in the order they were added. This is needed so that for example the
+    sequence of operations "INSERT x, DEL MARK x, INSERT x" is handled
+    correctly.
+
+ 2. 1 byte: Operation type (see ibuf_op_t).
+
+ 3. 1 byte: Flags. Currently only one flag exists, IBUF_REC_COMPACT.
+
+To ensure older records, which do not have counters to enforce correct
+sorting, are merged before any new records, ibuf_insert checks if we're
+trying to insert to a position that contains old-style records, and if so,
+refuses the insert. Thus, ibuf pages are gradually converted to the new
+format as their corresponding buffer pool pages are read into memory.
+*/
+
+
+/*	PREVENTING DEADLOCKS IN THE INSERT BUFFER SYSTEM
+
+If an OS thread performs any operation that brings in disk pages from
+non-system tablespaces into the buffer pool, or creates such a page there,
+then the operation may have as a side effect an insert buffer index tree
+compression. Thus, the tree latch of the insert buffer tree may be acquired
+in the x-mode, and also the file space latch of the system tablespace may
+be acquired in the x-mode.
+
+Also, an insert to an index in a non-system tablespace can have the same
+effect. How do we know this cannot lead to a deadlock of OS threads? There
+is a problem with the i\o-handler threads: they break the latching order
+because they own x-latches to pages which are on a lower level than the
+insert buffer tree latch, its page latches, and the tablespace latch an
+insert buffer operation can reserve.
+
+The solution is the following: Let all the tree and page latches connected
+with the insert buffer be later in the latching order than the fsp latch and
+fsp page latches.
+
+Insert buffer pages must be such that the insert buffer is never invoked
+when these pages are accessed as this would result in a recursion violating
+the latching order. We let a special i/o-handler thread take care of i/o to
+the insert buffer pages and the ibuf bitmap pages, as well as the fsp bitmap
+pages and the first inode page, which contains the inode of the ibuf tree: let
+us call all these ibuf pages. To prevent deadlocks, we do not let a read-ahead
+access both non-ibuf and ibuf pages.
+
+Then an i/o-handler for the insert buffer never needs to access recursively the
+insert buffer tree and thus obeys the latching order. On the other hand, other
+i/o-handlers for other tablespaces may require access to the insert buffer,
+but because all kinds of latches they need to access there are later in the
+latching order, no violation of the latching order occurs in this case,
+either.
+
+A problem is how to grow and contract an insert buffer tree. As it is later
+in the latching order than the fsp management, we have to reserve the fsp
+latch first, before adding or removing pages from the insert buffer tree.
+We let the insert buffer tree have its own file space management: a free
+list of pages linked to the tree root. To prevent recursive using of the
+insert buffer when adding pages to the tree, we must first load these pages
+to memory, obtaining a latch on them, and only after that add them to the
+free list of the insert buffer tree. More difficult is removing of pages
+from the free list. If there is an excess of pages in the free list of the
+ibuf tree, they might be needed if some thread reserves the fsp latch,
+intending to allocate more file space. So we do the following: if a thread
+reserves the fsp latch, we check the writer count field of the latch. If
+this field has value 1, it means that the thread did not own the latch
+before entering the fsp system, and the mtr of the thread contains no
+modifications to the fsp pages. Now we are free to reserve the ibuf latch,
+and check if there is an excess of pages in the free list. We can then, in a
+separate mini-transaction, take them out of the free list and free them to
+the fsp system.
+
+To avoid deadlocks in the ibuf system, we divide file pages into three levels:
+
+(1) non-ibuf pages,
+(2) ibuf tree pages and the pages in the ibuf tree free list, and
+(3) ibuf bitmap pages.
+
+No OS thread is allowed to access higher level pages if it has latches to
+lower level pages; even if the thread owns a B-tree latch it must not access
+the B-tree non-leaf pages if it has latches on lower level pages. Read-ahead
+is only allowed for level 1 and 2 pages. Dedicated i/o-handler threads handle
+exclusively level 1 i/o. A dedicated i/o handler thread handles exclusively
+level 2 i/o. However, if an OS thread does the i/o handling for itself, i.e.,
+it uses synchronous aio, it can access any pages, as long as it obeys the
+access order rules. */
+
+/** Table name for the insert buffer. */
+#define IBUF_TABLE_NAME		"SYS_IBUF_TABLE"
+
+/** Operations that can currently be buffered. */
+UNIV_INTERN ibuf_use_t	ibuf_use		= IBUF_USE_ALL;
+
+#if defined UNIV_DEBUG || defined UNIV_IBUF_DEBUG
+/** Flag to control insert buffer debugging. */
+UNIV_INTERN uint	ibuf_debug;
+#endif /* UNIV_DEBUG || UNIV_IBUF_DEBUG */
+
+/** The insert buffer control structure */
+UNIV_INTERN ibuf_t*	ibuf			= NULL;
+
+#ifdef UNIV_PFS_MUTEX
+UNIV_INTERN mysql_pfs_key_t	ibuf_pessimistic_insert_mutex_key;
+UNIV_INTERN mysql_pfs_key_t	ibuf_mutex_key;
+UNIV_INTERN mysql_pfs_key_t	ibuf_bitmap_mutex_key;
+#endif /* UNIV_PFS_MUTEX */
+
+#ifdef UNIV_IBUF_COUNT_DEBUG
+/** Number of tablespaces in the ibuf_counts array */
+#define IBUF_COUNT_N_SPACES	4
+/** Number of pages within each tablespace in the ibuf_counts array */
+#define IBUF_COUNT_N_PAGES	130000
+
+/** Buffered entry counts for file pages, used in debugging */
+static ulint	ibuf_counts[IBUF_COUNT_N_SPACES][IBUF_COUNT_N_PAGES];
+
+/******************************************************************//**
+Checks that the indexes to ibuf_counts[][] are within limits. */
+UNIV_INLINE
+void
+ibuf_count_check(
+/*=============*/
+	ulint	space_id,	/*!< in: space identifier */
+	ulint	page_no)	/*!< in: page number */
+{
+	if (space_id < IBUF_COUNT_N_SPACES && page_no < IBUF_COUNT_N_PAGES) {
+		return;
+	}
+
+	fprintf(stderr,
+		"InnoDB: UNIV_IBUF_COUNT_DEBUG limits space_id and page_no\n"
+		"InnoDB: and breaks crash recovery.\n"
+		"InnoDB: space_id=%lu, should be 0<=space_id<%lu\n"
+		"InnoDB: page_no=%lu, should be 0<=page_no<%lu\n",
+		(ulint) space_id, (ulint) IBUF_COUNT_N_SPACES,
+		(ulint) page_no, (ulint) IBUF_COUNT_N_PAGES);
+	ut_error;
+}
+#endif
+
+/** @name Offsets to the per-page bits in the insert buffer bitmap */
+/* @{ */
+#define	IBUF_BITMAP_FREE	0	/*!< Bits indicating the
+					amount of free space */
+#define IBUF_BITMAP_BUFFERED	2	/*!< TRUE if there are buffered
+					changes for the page */
+#define IBUF_BITMAP_IBUF	3	/*!< TRUE if page is a part of
+					the ibuf tree, excluding the
+					root page, or is in the free
+					list of the ibuf */
+/* @} */
+
+#define IBUF_REC_FIELD_SPACE	0	/*!< in the pre-4.1 format,
+					the page number. later, the space_id */
+#define IBUF_REC_FIELD_MARKER	1	/*!< starting with 4.1, a marker
+					consisting of 1 byte that is 0 */
+#define IBUF_REC_FIELD_PAGE	2	/*!< starting with 4.1, the
+					page number */
+#define IBUF_REC_FIELD_METADATA	3	/* the metadata field */
+#define IBUF_REC_FIELD_USER	4	/* first user field */
+
+/* Various constants for checking the type of an ibuf record and extracting
+data from it. For details, see the description of the record format at the
+top of this file. */
+
+/** @name Format of the IBUF_REC_FIELD_METADATA of an insert buffer record
+The fourth column in the MySQL 5.5 format contains an operation
+type, counter, and some flags. */
+/* @{ */
+#define IBUF_REC_INFO_SIZE	4	/*!< Combined size of info fields at
+					the beginning of the fourth field */
+#if IBUF_REC_INFO_SIZE >= DATA_NEW_ORDER_NULL_TYPE_BUF_SIZE
+# error "IBUF_REC_INFO_SIZE >= DATA_NEW_ORDER_NULL_TYPE_BUF_SIZE"
+#endif
+
+/* Offsets for the fields at the beginning of the fourth field */
+#define IBUF_REC_OFFSET_COUNTER	0	/*!< Operation counter */
+#define IBUF_REC_OFFSET_TYPE	2	/*!< Type of operation */
+#define IBUF_REC_OFFSET_FLAGS	3	/*!< Additional flags */
+
+/* Record flag masks */
+#define IBUF_REC_COMPACT	0x1	/*!< Set in
+					IBUF_REC_OFFSET_FLAGS if the
+					user index is in COMPACT
+					format or later */
+
+
+/** The mutex used to block pessimistic inserts to ibuf trees */
+static ib_mutex_t	ibuf_pessimistic_insert_mutex;
+
+/** The mutex protecting the insert buffer structs */
+static ib_mutex_t	ibuf_mutex;
+
+/** The mutex protecting the insert buffer bitmaps */
+static ib_mutex_t	ibuf_bitmap_mutex;
+
+/** The area in pages from which contract looks for page numbers for merge */
+#define	IBUF_MERGE_AREA			8UL
+
+/** Inside the merge area, pages which have at most 1 per this number less
+buffered entries compared to maximum volume that can buffered for a single
+page are merged along with the page whose buffer became full */
+#define IBUF_MERGE_THRESHOLD		4
+
+/** In ibuf_contract at most this number of pages is read to memory in one
+batch, in order to merge the entries for them in the insert buffer */
+#define	IBUF_MAX_N_PAGES_MERGED		IBUF_MERGE_AREA
+
+/** If the combined size of the ibuf trees exceeds ibuf->max_size by this
+many pages, we start to contract it in connection to inserts there, using
+non-synchronous contract */
+#define IBUF_CONTRACT_ON_INSERT_NON_SYNC	0
+
+/** If the combined size of the ibuf trees exceeds ibuf->max_size by this
+many pages, we start to contract it in connection to inserts there, using
+synchronous contract */
+#define IBUF_CONTRACT_ON_INSERT_SYNC		5
+
+/** If the combined size of the ibuf trees exceeds ibuf->max_size by
+this many pages, we start to contract it synchronous contract, but do
+not insert */
+#define IBUF_CONTRACT_DO_NOT_INSERT		10
+
+/* TODO: how to cope with drop table if there are records in the insert
+buffer for the indexes of the table? Is there actually any problem,
+because ibuf merge is done to a page when it is read in, and it is
+still physically like the index page even if the index would have been
+dropped! So, there seems to be no problem. */
+
+/******************************************************************//**
+Sets the flag in the current mini-transaction record indicating we're
+inside an insert buffer routine. */
+UNIV_INLINE
+void
+ibuf_enter(
+/*=======*/
+	mtr_t*	mtr)	/*!< in/out: mini-transaction */
+{
+	ut_ad(!mtr->inside_ibuf);
+	mtr->inside_ibuf = TRUE;
+}
+
+/******************************************************************//**
+Sets the flag in the current mini-transaction record indicating we're
+exiting an insert buffer routine. */
+UNIV_INLINE
+void
+ibuf_exit(
+/*======*/
+	mtr_t*	mtr)	/*!< in/out: mini-transaction */
+{
+	ut_ad(mtr->inside_ibuf);
+	mtr->inside_ibuf = FALSE;
+}
+
+/**************************************************************//**
+Commits an insert buffer mini-transaction and sets the persistent
+cursor latch mode to BTR_NO_LATCHES, that is, detaches the cursor. */
+UNIV_INLINE
+void
+ibuf_btr_pcur_commit_specify_mtr(
+/*=============================*/
+	btr_pcur_t*	pcur,	/*!< in/out: persistent cursor */
+	mtr_t*		mtr)	/*!< in/out: mini-transaction */
+{
+	ut_d(ibuf_exit(mtr));
+	btr_pcur_commit_specify_mtr(pcur, mtr);
+}
+
+/******************************************************************//**
+Gets the ibuf header page and x-latches it.
+@return	insert buffer header page */
+static
+page_t*
+ibuf_header_page_get(
+/*=================*/
+	mtr_t*	mtr)	/*!< in/out: mini-transaction */
+{
+	buf_block_t*	block;
+
+	ut_ad(!ibuf_inside(mtr));
+
+	block = buf_page_get(
+		IBUF_SPACE_ID, 0, FSP_IBUF_HEADER_PAGE_NO, RW_X_LATCH, mtr);
+	buf_block_dbg_add_level(block, SYNC_IBUF_HEADER);
+
+	return(buf_block_get_frame(block));
+}
+
+/******************************************************************//**
+Gets the root page and x-latches it.
+@return	insert buffer tree root page */
+static
+page_t*
+ibuf_tree_root_get(
+/*===============*/
+	mtr_t*		mtr)	/*!< in: mtr */
+{
+	buf_block_t*	block;
+	page_t*		root;
+
+	ut_ad(ibuf_inside(mtr));
+	ut_ad(mutex_own(&ibuf_mutex));
+
+	mtr_x_lock(dict_index_get_lock(ibuf->index), mtr);
+
+	block = buf_page_get(
+		IBUF_SPACE_ID, 0, FSP_IBUF_TREE_ROOT_PAGE_NO, RW_X_LATCH, mtr);
+
+	buf_block_dbg_add_level(block, SYNC_IBUF_TREE_NODE_NEW);
+
+	root = buf_block_get_frame(block);
+
+	ut_ad(page_get_space_id(root) == IBUF_SPACE_ID);
+	ut_ad(page_get_page_no(root) == FSP_IBUF_TREE_ROOT_PAGE_NO);
+	ut_ad(ibuf->empty == page_is_empty(root));
+
+	return(root);
+}
+
+#ifdef UNIV_IBUF_COUNT_DEBUG
+/******************************************************************//**
+Gets the ibuf count for a given page.
+@return number of entries in the insert buffer currently buffered for
+this page */
+UNIV_INTERN
+ulint
+ibuf_count_get(
+/*===========*/
+	ulint	space,	/*!< in: space id */
+	ulint	page_no)/*!< in: page number */
+{
+	ibuf_count_check(space, page_no);
+
+	return(ibuf_counts[space][page_no]);
+}
+
+/******************************************************************//**
+Sets the ibuf count for a given page. */
+static
+void
+ibuf_count_set(
+/*===========*/
+	ulint	space,	/*!< in: space id */
+	ulint	page_no,/*!< in: page number */
+	ulint	val)	/*!< in: value to set */
+{
+	ibuf_count_check(space, page_no);
+	ut_a(val < UNIV_PAGE_SIZE);
+
+	ibuf_counts[space][page_no] = val;
+}
+#endif
+
+/******************************************************************//**
+Closes insert buffer and frees the data structures. */
+UNIV_INTERN
+void
+ibuf_close(void)
+/*============*/
+{
+	mutex_free(&ibuf_pessimistic_insert_mutex);
+	memset(&ibuf_pessimistic_insert_mutex,
+	       0x0, sizeof(ibuf_pessimistic_insert_mutex));
+
+	mutex_free(&ibuf_mutex);
+	memset(&ibuf_mutex, 0x0, sizeof(ibuf_mutex));
+
+	mutex_free(&ibuf_bitmap_mutex);
+	memset(&ibuf_bitmap_mutex, 0x0, sizeof(ibuf_mutex));
+
+	mem_free(ibuf);
+	ibuf = NULL;
+}
+
+/******************************************************************//**
+Updates the size information of the ibuf, assuming the segment size has not
+changed. */
+static
+void
+ibuf_size_update(
+/*=============*/
+	const page_t*	root,	/*!< in: ibuf tree root */
+	mtr_t*		mtr)	/*!< in: mtr */
+{
+	ut_ad(mutex_own(&ibuf_mutex));
+
+	ibuf->free_list_len = flst_get_len(root + PAGE_HEADER
+					   + PAGE_BTR_IBUF_FREE_LIST, mtr);
+
+	ibuf->height = 1 + btr_page_get_level(root, mtr);
+
+	/* the '1 +' is the ibuf header page */
+	ibuf->size = ibuf->seg_size - (1 + ibuf->free_list_len);
+}
+
+/******************************************************************//**
+Creates the insert buffer data structure at a database startup and initializes
+the data structures for the insert buffer. */
+UNIV_INTERN
+void
+ibuf_init_at_db_start(void)
+/*=======================*/
+{
+	page_t*		root;
+	mtr_t		mtr;
+	dict_table_t*	table;
+	mem_heap_t*	heap;
+	dict_index_t*	index;
+	ulint		n_used;
+	page_t*		header_page;
+	dberr_t		error;
+
+	ibuf = static_cast<ibuf_t*>(mem_zalloc(sizeof(ibuf_t)));
+
+	/* At startup we intialize ibuf to have a maximum of
+	CHANGE_BUFFER_DEFAULT_SIZE in terms of percentage of the
+	buffer pool size. Once ibuf struct is initialized this
+	value is updated with the user supplied size by calling
+	ibuf_max_size_update(). */
+	ibuf->max_size = ((buf_pool_get_curr_size() / UNIV_PAGE_SIZE)
+			  * CHANGE_BUFFER_DEFAULT_SIZE) / 100;
+
+	mutex_create(ibuf_pessimistic_insert_mutex_key,
+		     &ibuf_pessimistic_insert_mutex,
+		     SYNC_IBUF_PESS_INSERT_MUTEX);
+
+	mutex_create(ibuf_mutex_key,
+		     &ibuf_mutex, SYNC_IBUF_MUTEX);
+
+	mutex_create(ibuf_bitmap_mutex_key,
+		     &ibuf_bitmap_mutex, SYNC_IBUF_BITMAP_MUTEX);
+
+	mtr_start(&mtr);
+
+	mutex_enter(&ibuf_mutex);
+
+	mtr_x_lock(fil_space_get_latch(IBUF_SPACE_ID, NULL), &mtr);
+
+	header_page = ibuf_header_page_get(&mtr);
+
+	fseg_n_reserved_pages(header_page + IBUF_HEADER + IBUF_TREE_SEG_HEADER,
+			      &n_used, &mtr);
+	ibuf_enter(&mtr);
+
+	ut_ad(n_used >= 2);
+
+	ibuf->seg_size = n_used;
+
+	{
+		buf_block_t*	block;
+
+		block = buf_page_get(
+			IBUF_SPACE_ID, 0, FSP_IBUF_TREE_ROOT_PAGE_NO,
+			RW_X_LATCH, &mtr);
+		buf_block_dbg_add_level(block, SYNC_IBUF_TREE_NODE);
+
+		root = buf_block_get_frame(block);
+	}
+
+	ibuf_size_update(root, &mtr);
+	mutex_exit(&ibuf_mutex);
+
+	ibuf->empty = page_is_empty(root);
+	ibuf_mtr_commit(&mtr);
+
+	heap = mem_heap_create(450);
+
+	/* Use old-style record format for the insert buffer. */
+	table = dict_mem_table_create(IBUF_TABLE_NAME, IBUF_SPACE_ID, 1, 0, 0);
+
+	dict_mem_table_add_col(table, heap, "DUMMY_COLUMN", DATA_BINARY, 0, 0);
+
+	table->id = DICT_IBUF_ID_MIN + IBUF_SPACE_ID;
+
+	dict_table_add_to_cache(table, FALSE, heap);
+	mem_heap_free(heap);
+
+	index = dict_mem_index_create(
+		IBUF_TABLE_NAME, "CLUST_IND",
+		IBUF_SPACE_ID, DICT_CLUSTERED | DICT_UNIVERSAL | DICT_IBUF, 1);
+
+	dict_mem_index_add_field(index, "DUMMY_COLUMN", 0);
+
+	index->id = DICT_IBUF_ID_MIN + IBUF_SPACE_ID;
+
+	error = dict_index_add_to_cache(table, index,
+					FSP_IBUF_TREE_ROOT_PAGE_NO, FALSE);
+	ut_a(error == DB_SUCCESS);
+
+	ibuf->index = dict_table_get_first_index(table);
+}
+
+/*********************************************************************//**
+Updates the max_size value for ibuf. */
+UNIV_INTERN
+void
+ibuf_max_size_update(
+/*=================*/
+	ulint	new_val)	/*!< in: new value in terms of
+				percentage of the buffer pool size */
+{
+	ulint	new_size = ((buf_pool_get_curr_size() / UNIV_PAGE_SIZE)
+			    * new_val) / 100;
+	mutex_enter(&ibuf_mutex);
+	ibuf->max_size = new_size;
+	mutex_exit(&ibuf_mutex);
+}
+
+
+#endif /* !UNIV_HOTBACKUP */
+/*********************************************************************//**
+Initializes an ibuf bitmap page. */
+UNIV_INTERN
+void
+ibuf_bitmap_page_init(
+/*==================*/
+	buf_block_t*	block,	/*!< in: bitmap page */
+	mtr_t*		mtr)	/*!< in: mtr */
+{
+	page_t*	page;
+	ulint	byte_offset;
+	ulint	zip_size = buf_block_get_zip_size(block);
+
+	ut_a(ut_is_2pow(zip_size));
+
+	page = buf_block_get_frame(block);
+	fil_page_set_type(page, FIL_PAGE_IBUF_BITMAP);
+
+	/* Write all zeros to the bitmap */
+
+	if (!zip_size) {
+		byte_offset = UT_BITS_IN_BYTES(UNIV_PAGE_SIZE
+					       * IBUF_BITS_PER_PAGE);
+	} else {
+		byte_offset = UT_BITS_IN_BYTES(zip_size * IBUF_BITS_PER_PAGE);
+	}
+
+	memset(page + IBUF_BITMAP, 0, byte_offset);
+
+	/* The remaining area (up to the page trailer) is uninitialized. */
+
+#ifndef UNIV_HOTBACKUP
+	mlog_write_initial_log_record(page, MLOG_IBUF_BITMAP_INIT, mtr);
+#endif /* !UNIV_HOTBACKUP */
+}
+
+/*********************************************************************//**
+Parses a redo log record of an ibuf bitmap page init.
+@return	end of log record or NULL */
+UNIV_INTERN
+byte*
+ibuf_parse_bitmap_init(
+/*===================*/
+	byte*		ptr,	/*!< in: buffer */
+	byte*		end_ptr __attribute__((unused)), /*!< in: buffer end */
+	buf_block_t*	block,	/*!< in: block or NULL */
+	mtr_t*		mtr)	/*!< in: mtr or NULL */
+{
+	ut_ad(ptr && end_ptr);
+
+	if (block) {
+		ibuf_bitmap_page_init(block, mtr);
+	}
+
+	return(ptr);
+}
+#ifndef UNIV_HOTBACKUP
+# ifdef UNIV_DEBUG
+/** Gets the desired bits for a given page from a bitmap page.
+@param page	in: bitmap page
+@param offset	in: page whose bits to get
+@param zs	in: compressed page size in bytes; 0 for uncompressed pages
+@param bit	in: IBUF_BITMAP_FREE, IBUF_BITMAP_BUFFERED, ...
+@param mtr	in: mini-transaction holding an x-latch on the bitmap page
+@return	value of bits */
+#  define ibuf_bitmap_page_get_bits(page, offset, zs, bit, mtr)	\
+	ibuf_bitmap_page_get_bits_low(page, offset, zs,	\
+				      MTR_MEMO_PAGE_X_FIX, mtr, bit)
+# else /* UNIV_DEBUG */
+/** Gets the desired bits for a given page from a bitmap page.
+@param page	in: bitmap page
+@param offset	in: page whose bits to get
+@param zs	in: compressed page size in bytes; 0 for uncompressed pages
+@param bit	in: IBUF_BITMAP_FREE, IBUF_BITMAP_BUFFERED, ...
+@param mtr	in: mini-transaction holding an x-latch on the bitmap page
+@return	value of bits */
+#  define ibuf_bitmap_page_get_bits(page, offset, zs, bit, mtr)		\
+	ibuf_bitmap_page_get_bits_low(page, offset, zs, bit)
+# endif /* UNIV_DEBUG */
+
+/********************************************************************//**
+Gets the desired bits for a given page from a bitmap page.
+@return	value of bits */
+UNIV_INLINE
+ulint
+ibuf_bitmap_page_get_bits_low(
+/*==========================*/
+	const page_t*	page,	/*!< in: bitmap page */
+	ulint		page_no,/*!< in: page whose bits to get */
+	ulint		zip_size,/*!< in: compressed page size in bytes;
+				0 for uncompressed pages */
+#ifdef UNIV_DEBUG
+	ulint		latch_type,
+				/*!< in: MTR_MEMO_PAGE_X_FIX,
+				MTR_MEMO_BUF_FIX, ... */
+	mtr_t*		mtr,	/*!< in: mini-transaction holding latch_type
+				on the bitmap page */
+#endif /* UNIV_DEBUG */
+	ulint		bit)	/*!< in: IBUF_BITMAP_FREE,
+				IBUF_BITMAP_BUFFERED, ... */
+{
+	ulint	byte_offset;
+	ulint	bit_offset;
+	ulint	map_byte;
+	ulint	value;
+
+	ut_ad(bit < IBUF_BITS_PER_PAGE);
+#if IBUF_BITS_PER_PAGE % 2
+# error "IBUF_BITS_PER_PAGE % 2 != 0"
+#endif
+	ut_ad(ut_is_2pow(zip_size));
+	ut_ad(mtr_memo_contains_page(mtr, page, latch_type));
+
+	if (!zip_size) {
+		bit_offset = (page_no % UNIV_PAGE_SIZE) * IBUF_BITS_PER_PAGE
+			+ bit;
+	} else {
+		bit_offset = (page_no & (zip_size - 1)) * IBUF_BITS_PER_PAGE
+			+ bit;
+	}
+
+	byte_offset = bit_offset / 8;
+	bit_offset = bit_offset % 8;
+
+	ut_ad(byte_offset + IBUF_BITMAP < UNIV_PAGE_SIZE);
+
+	map_byte = mach_read_from_1(page + IBUF_BITMAP + byte_offset);
+
+	value = ut_bit_get_nth(map_byte, bit_offset);
+
+	if (bit == IBUF_BITMAP_FREE) {
+		ut_ad(bit_offset + 1 < 8);
+
+		value = value * 2 + ut_bit_get_nth(map_byte, bit_offset + 1);
+	}
+
+	return(value);
+}
+
+/********************************************************************//**
+Sets the desired bit for a given page in a bitmap page. */
+static
+void
+ibuf_bitmap_page_set_bits(
+/*======================*/
+	page_t*	page,	/*!< in: bitmap page */
+	ulint	page_no,/*!< in: page whose bits to set */
+	ulint	zip_size,/*!< in: compressed page size in bytes;
+			0 for uncompressed pages */
+	ulint	bit,	/*!< in: IBUF_BITMAP_FREE, IBUF_BITMAP_BUFFERED, ... */
+	ulint	val,	/*!< in: value to set */
+	mtr_t*	mtr)	/*!< in: mtr containing an x-latch to the bitmap page */
+{
+	ulint	byte_offset;
+	ulint	bit_offset;
+	ulint	map_byte;
+
+	ut_ad(bit < IBUF_BITS_PER_PAGE);
+#if IBUF_BITS_PER_PAGE % 2
+# error "IBUF_BITS_PER_PAGE % 2 != 0"
+#endif
+	ut_ad(ut_is_2pow(zip_size));
+	ut_ad(mtr_memo_contains_page(mtr, page, MTR_MEMO_PAGE_X_FIX));
+#ifdef UNIV_IBUF_COUNT_DEBUG
+	ut_a((bit != IBUF_BITMAP_BUFFERED) || (val != FALSE)
+	     || (0 == ibuf_count_get(page_get_space_id(page),
+				     page_no)));
+#endif
+	if (!zip_size) {
+		bit_offset = (page_no % UNIV_PAGE_SIZE) * IBUF_BITS_PER_PAGE
+			+ bit;
+	} else {
+		bit_offset = (page_no & (zip_size - 1)) * IBUF_BITS_PER_PAGE
+			+ bit;
+	}
+
+	byte_offset = bit_offset / 8;
+	bit_offset = bit_offset % 8;
+
+	ut_ad(byte_offset + IBUF_BITMAP < UNIV_PAGE_SIZE);
+
+	map_byte = mach_read_from_1(page + IBUF_BITMAP + byte_offset);
+
+	if (bit == IBUF_BITMAP_FREE) {
+		ut_ad(bit_offset + 1 < 8);
+		ut_ad(val <= 3);
+
+		map_byte = ut_bit_set_nth(map_byte, bit_offset, val / 2);
+		map_byte = ut_bit_set_nth(map_byte, bit_offset + 1, val % 2);
+	} else {
+		ut_ad(val <= 1);
+		map_byte = ut_bit_set_nth(map_byte, bit_offset, val);
+	}
+
+	mlog_write_ulint(page + IBUF_BITMAP + byte_offset, map_byte,
+			 MLOG_1BYTE, mtr);
+}
+
+/********************************************************************//**
+Calculates the bitmap page number for a given page number.
+@return	the bitmap page number where the file page is mapped */
+UNIV_INLINE
+ulint
+ibuf_bitmap_page_no_calc(
+/*=====================*/
+	ulint	zip_size,	/*!< in: compressed page size in bytes;
+				0 for uncompressed pages */
+	ulint	page_no)	/*!< in: tablespace page number */
+{
+	ut_ad(ut_is_2pow(zip_size));
+
+	if (!zip_size) {
+		return(FSP_IBUF_BITMAP_OFFSET
+		       + (page_no & ~(UNIV_PAGE_SIZE - 1)));
+	} else {
+		return(FSP_IBUF_BITMAP_OFFSET
+		       + (page_no & ~(zip_size - 1)));
+	}
+}
+
+/********************************************************************//**
+Gets the ibuf bitmap page where the bits describing a given file page are
+stored.
+@return bitmap page where the file page is mapped, that is, the bitmap
+page containing the descriptor bits for the file page; the bitmap page
+is x-latched */
+static
+page_t*
+ibuf_bitmap_get_map_page_func(
+/*==========================*/
+	ulint		space,	/*!< in: space id of the file page */
+	ulint		page_no,/*!< in: page number of the file page */
+	ulint		zip_size,/*!< in: compressed page size in bytes;
+				0 for uncompressed pages */
+	const char*	file,	/*!< in: file name */
+	ulint		line,	/*!< in: line where called */
+	mtr_t*		mtr)	/*!< in: mtr */
+{
+	buf_block_t*	block;
+
+	block = buf_page_get_gen(space, zip_size,
+				 ibuf_bitmap_page_no_calc(zip_size, page_no),
+				 RW_X_LATCH, NULL, BUF_GET,
+				 file, line, mtr);
+	buf_block_dbg_add_level(block, SYNC_IBUF_BITMAP);
+
+	return(buf_block_get_frame(block));
+}
+
+/********************************************************************//**
+Gets the ibuf bitmap page where the bits describing a given file page are
+stored.
+@return bitmap page where the file page is mapped, that is, the bitmap
+page containing the descriptor bits for the file page; the bitmap page
+is x-latched
+@param space	in: space id of the file page
+@param page_no	in: page number of the file page
+@param zip_size	in: compressed page size in bytes; 0 for uncompressed pages
+@param mtr	in: mini-transaction */
+#define ibuf_bitmap_get_map_page(space, page_no, zip_size, mtr)		\
+	ibuf_bitmap_get_map_page_func(space, page_no, zip_size,		\
+				      __FILE__, __LINE__, mtr)
+
+/************************************************************************//**
+Sets the free bits of the page in the ibuf bitmap. This is done in a separate
+mini-transaction, hence this operation does not restrict further work to only
+ibuf bitmap operations, which would result if the latch to the bitmap page
+were kept. */
+UNIV_INLINE
+void
+ibuf_set_free_bits_low(
+/*===================*/
+	ulint			zip_size,/*!< in: compressed page size in bytes;
+					0 for uncompressed pages */
+	const buf_block_t*	block,	/*!< in: index page; free bits are set if
+					the index is non-clustered and page
+					level is 0 */
+	ulint			val,	/*!< in: value to set: < 4 */
+	mtr_t*			mtr)	/*!< in/out: mtr */
+{
+	page_t*	bitmap_page;
+	ulint	space;
+	ulint	page_no;
+
+	if (!page_is_leaf(buf_block_get_frame(block))) {
+
+		return;
+	}
+
+	space = buf_block_get_space(block);
+	page_no = buf_block_get_page_no(block);
+	bitmap_page = ibuf_bitmap_get_map_page(space, page_no, zip_size, mtr);
+#ifdef UNIV_IBUF_DEBUG
+# if 0
+	fprintf(stderr,
+		"Setting space %lu page %lu free bits to %lu should be %lu\n",
+		space, page_no, val,
+		ibuf_index_page_calc_free(zip_size, block));
+# endif
+
+	ut_a(val <= ibuf_index_page_calc_free(zip_size, block));
+#endif /* UNIV_IBUF_DEBUG */
+	ibuf_bitmap_page_set_bits(bitmap_page, page_no, zip_size,
+				  IBUF_BITMAP_FREE, val, mtr);
+}
+
+/************************************************************************//**
+Sets the free bit of the page in the ibuf bitmap. This is done in a separate
+mini-transaction, hence this operation does not restrict further work to only
+ibuf bitmap operations, which would result if the latch to the bitmap page
+were kept. */
+UNIV_INTERN
+void
+ibuf_set_free_bits_func(
+/*====================*/
+	buf_block_t*	block,	/*!< in: index page of a non-clustered index;
+				free bit is reset if page level is 0 */
+#ifdef UNIV_IBUF_DEBUG
+	ulint		max_val,/*!< in: ULINT_UNDEFINED or a maximum
+				value which the bits must have before
+				setting; this is for debugging */
+#endif /* UNIV_IBUF_DEBUG */
+	ulint		val)	/*!< in: value to set: < 4 */
+{
+	mtr_t	mtr;
+	page_t*	page;
+	page_t*	bitmap_page;
+	ulint	space;
+	ulint	page_no;
+	ulint	zip_size;
+
+	page = buf_block_get_frame(block);
+
+	if (!page_is_leaf(page)) {
+
+		return;
+	}
+
+	mtr_start(&mtr);
+
+	space = buf_block_get_space(block);
+	page_no = buf_block_get_page_no(block);
+	zip_size = buf_block_get_zip_size(block);
+	bitmap_page = ibuf_bitmap_get_map_page(space, page_no, zip_size, &mtr);
+
+#ifdef UNIV_IBUF_DEBUG
+	if (max_val != ULINT_UNDEFINED) {
+		ulint	old_val;
+
+		old_val = ibuf_bitmap_page_get_bits(
+			bitmap_page, page_no, zip_size,
+			IBUF_BITMAP_FREE, &mtr);
+# if 0
+		if (old_val != max_val) {
+			fprintf(stderr,
+				"Ibuf: page %lu old val %lu max val %lu\n",
+				page_get_page_no(page),
+				old_val, max_val);
+		}
+# endif
+
+		ut_a(old_val <= max_val);
+	}
+# if 0
+	fprintf(stderr, "Setting page no %lu free bits to %lu should be %lu\n",
+		page_get_page_no(page), val,
+		ibuf_index_page_calc_free(zip_size, block));
+# endif
+
+	ut_a(val <= ibuf_index_page_calc_free(zip_size, block));
+#endif /* UNIV_IBUF_DEBUG */
+	ibuf_bitmap_page_set_bits(bitmap_page, page_no, zip_size,
+				  IBUF_BITMAP_FREE, val, &mtr);
+	mtr_commit(&mtr);
+}
+
+/************************************************************************//**
+Resets the free bits of the page in the ibuf bitmap. This is done in a
+separate mini-transaction, hence this operation does not restrict
+further work to only ibuf bitmap operations, which would result if the
+latch to the bitmap page were kept.  NOTE: The free bits in the insert
+buffer bitmap must never exceed the free space on a page.  It is safe
+to decrement or reset the bits in the bitmap in a mini-transaction
+that is committed before the mini-transaction that affects the free
+space. */
+UNIV_INTERN
+void
+ibuf_reset_free_bits(
+/*=================*/
+	buf_block_t*	block)	/*!< in: index page; free bits are set to 0
+				if the index is a non-clustered
+				non-unique, and page level is 0 */
+{
+	ibuf_set_free_bits(block, 0, ULINT_UNDEFINED);
+}
+
+/**********************************************************************//**
+Updates the free bits for an uncompressed page to reflect the present
+state.  Does this in the mtr given, which means that the latching
+order rules virtually prevent any further operations for this OS
+thread until mtr is committed.  NOTE: The free bits in the insert
+buffer bitmap must never exceed the free space on a page.  It is safe
+to set the free bits in the same mini-transaction that updated the
+page. */
+UNIV_INTERN
+void
+ibuf_update_free_bits_low(
+/*======================*/
+	const buf_block_t*	block,		/*!< in: index page */
+	ulint			max_ins_size,	/*!< in: value of
+						maximum insert size
+						with reorganize before
+						the latest operation
+						performed to the page */
+	mtr_t*			mtr)		/*!< in/out: mtr */
+{
+	ulint	before;
+	ulint	after;
+
+	ut_a(!buf_block_get_page_zip(block));
+
+	before = ibuf_index_page_calc_free_bits(0, max_ins_size);
+
+	after = ibuf_index_page_calc_free(0, block);
+
+	/* This approach cannot be used on compressed pages, since the
+	computed value of "before" often does not match the current
+	state of the bitmap.  This is because the free space may
+	increase or decrease when a compressed page is reorganized. */
+	if (before != after) {
+		ibuf_set_free_bits_low(0, block, after, mtr);
+	}
+}
+
+/**********************************************************************//**
+Updates the free bits for a compressed page to reflect the present
+state.  Does this in the mtr given, which means that the latching
+order rules virtually prevent any further operations for this OS
+thread until mtr is committed.  NOTE: The free bits in the insert
+buffer bitmap must never exceed the free space on a page.  It is safe
+to set the free bits in the same mini-transaction that updated the
+page. */
+UNIV_INTERN
+void
+ibuf_update_free_bits_zip(
+/*======================*/
+	buf_block_t*	block,	/*!< in/out: index page */
+	mtr_t*		mtr)	/*!< in/out: mtr */
+{
+	page_t*	bitmap_page;
+	ulint	space;
+	ulint	page_no;
+	ulint	zip_size;
+	ulint	after;
+
+	space = buf_block_get_space(block);
+	page_no = buf_block_get_page_no(block);
+	zip_size = buf_block_get_zip_size(block);
+
+	ut_a(page_is_leaf(buf_block_get_frame(block)));
+	ut_a(zip_size);
+
+	bitmap_page = ibuf_bitmap_get_map_page(space, page_no, zip_size, mtr);
+
+	after = ibuf_index_page_calc_free_zip(zip_size, block);
+
+	if (after == 0) {
+		/* We move the page to the front of the buffer pool LRU list:
+		the purpose of this is to prevent those pages to which we
+		cannot make inserts using the insert buffer from slipping
+		out of the buffer pool */
+
+		buf_page_make_young(&block->page);
+	}
+
+	ibuf_bitmap_page_set_bits(bitmap_page, page_no, zip_size,
+				  IBUF_BITMAP_FREE, after, mtr);
+}
+
+/**********************************************************************//**
+Updates the free bits for the two pages to reflect the present state.
+Does this in the mtr given, which means that the latching order rules
+virtually prevent any further operations until mtr is committed.
+NOTE: The free bits in the insert buffer bitmap must never exceed the
+free space on a page.  It is safe to set the free bits in the same
+mini-transaction that updated the pages. */
+UNIV_INTERN
+void
+ibuf_update_free_bits_for_two_pages_low(
+/*====================================*/
+	ulint		zip_size,/*!< in: compressed page size in bytes;
+				0 for uncompressed pages */
+	buf_block_t*	block1,	/*!< in: index page */
+	buf_block_t*	block2,	/*!< in: index page */
+	mtr_t*		mtr)	/*!< in: mtr */
+{
+	ulint	state;
+
+	/* As we have to x-latch two random bitmap pages, we have to acquire
+	the bitmap mutex to prevent a deadlock with a similar operation
+	performed by another OS thread. */
+
+	mutex_enter(&ibuf_bitmap_mutex);
+
+	state = ibuf_index_page_calc_free(zip_size, block1);
+
+	ibuf_set_free_bits_low(zip_size, block1, state, mtr);
+
+	state = ibuf_index_page_calc_free(zip_size, block2);
+
+	ibuf_set_free_bits_low(zip_size, block2, state, mtr);
+
+	mutex_exit(&ibuf_bitmap_mutex);
+}
+
+/**********************************************************************//**
+Returns TRUE if the page is one of the fixed address ibuf pages.
+@return	TRUE if a fixed address ibuf i/o page */
+UNIV_INLINE
+ibool
+ibuf_fixed_addr_page(
+/*=================*/
+	ulint	space,	/*!< in: space id */
+	ulint	zip_size,/*!< in: compressed page size in bytes;
+			0 for uncompressed pages */
+	ulint	page_no)/*!< in: page number */
+{
+	return((space == IBUF_SPACE_ID && page_no == IBUF_TREE_ROOT_PAGE_NO)
+	       || ibuf_bitmap_page(zip_size, page_no));
+}
+
+/***********************************************************************//**
+Checks if a page is a level 2 or 3 page in the ibuf hierarchy of pages.
+Must not be called when recv_no_ibuf_operations==TRUE.
+@return	TRUE if level 2 or level 3 page */
+UNIV_INTERN
+ibool
+ibuf_page_low(
+/*==========*/
+	ulint		space,	/*!< in: space id */
+	ulint		zip_size,/*!< in: compressed page size in bytes, or 0 */
+	ulint		page_no,/*!< in: page number */
+#ifdef UNIV_DEBUG
+	ibool		x_latch,/*!< in: FALSE if relaxed check
+				(avoid latching the bitmap page) */
+#endif /* UNIV_DEBUG */
+	const char*	file,	/*!< in: file name */
+	ulint		line,	/*!< in: line where called */
+	mtr_t*		mtr)	/*!< in: mtr which will contain an
+				x-latch to the bitmap page if the page
+				is not one of the fixed address ibuf
+				pages, or NULL, in which case a new
+				transaction is created. */
+{
+	ibool	ret;
+	mtr_t	local_mtr;
+	page_t*	bitmap_page;
+
+	ut_ad(!recv_no_ibuf_operations);
+	ut_ad(x_latch || mtr == NULL);
+
+	if (ibuf_fixed_addr_page(space, zip_size, page_no)) {
+
+		return(TRUE);
+	} else if (space != IBUF_SPACE_ID) {
+
+		return(FALSE);
+	}
+
+	ut_ad(fil_space_get_type(IBUF_SPACE_ID) == FIL_TABLESPACE);
+
+#ifdef UNIV_DEBUG
+	if (!x_latch) {
+		mtr_start(&local_mtr);
+
+		/* Get the bitmap page without a page latch, so that
+		we will not be violating the latching order when
+		another bitmap page has already been latched by this
+		thread. The page will be buffer-fixed, and thus it
+		cannot be removed or relocated while we are looking at
+		it. The contents of the page could change, but the
+		IBUF_BITMAP_IBUF bit that we are interested in should
+		not be modified by any other thread. Nobody should be
+		calling ibuf_add_free_page() or ibuf_remove_free_page()
+		while the page is linked to the insert buffer b-tree. */
+
+		bitmap_page = buf_block_get_frame(
+			buf_page_get_gen(
+				space, zip_size,
+				ibuf_bitmap_page_no_calc(zip_size, page_no),
+				RW_NO_LATCH, NULL, BUF_GET_NO_LATCH,
+				file, line, &local_mtr));
+
+		ret = ibuf_bitmap_page_get_bits_low(
+			bitmap_page, page_no, zip_size,
+			MTR_MEMO_BUF_FIX, &local_mtr, IBUF_BITMAP_IBUF);
+
+		mtr_commit(&local_mtr);
+		return(ret);
+	}
+#endif /* UNIV_DEBUG */
+
+	if (mtr == NULL) {
+		mtr = &local_mtr;
+		mtr_start(mtr);
+	}
+
+	bitmap_page = ibuf_bitmap_get_map_page_func(space, page_no, zip_size,
+						    file, line, mtr);
+
+	ret = ibuf_bitmap_page_get_bits(bitmap_page, page_no, zip_size,
+					IBUF_BITMAP_IBUF, mtr);
+
+	if (mtr == &local_mtr) {
+		mtr_commit(mtr);
+	}
+
+	return(ret);
+}
+
+#ifdef UNIV_DEBUG
+# define ibuf_rec_get_page_no(mtr,rec) ibuf_rec_get_page_no_func(mtr,rec)
+#else /* UNIV_DEBUG */
+# define ibuf_rec_get_page_no(mtr,rec) ibuf_rec_get_page_no_func(rec)
+#endif /* UNIV_DEBUG */
+
+/********************************************************************//**
+Returns the page number field of an ibuf record.
+@return	page number */
+static
+ulint
+ibuf_rec_get_page_no_func(
+/*======================*/
+#ifdef UNIV_DEBUG
+	mtr_t*		mtr,	/*!< in: mini-transaction owning rec */
+#endif /* UNIV_DEBUG */
+	const rec_t*	rec)	/*!< in: ibuf record */
+{
+	const byte*	field;
+	ulint		len;
+
+	ut_ad(mtr_memo_contains_page(mtr, rec, MTR_MEMO_PAGE_X_FIX)
+	      || mtr_memo_contains_page(mtr, rec, MTR_MEMO_PAGE_S_FIX));
+	ut_ad(ibuf_inside(mtr));
+	ut_ad(rec_get_n_fields_old(rec) > 2);
+
+	field = rec_get_nth_field_old(rec, IBUF_REC_FIELD_MARKER, &len);
+
+	ut_a(len == 1);
+
+	field = rec_get_nth_field_old(rec, IBUF_REC_FIELD_PAGE, &len);
+
+	ut_a(len == 4);
+
+	return(mach_read_from_4(field));
+}
+
+#ifdef UNIV_DEBUG
+# define ibuf_rec_get_space(mtr,rec) ibuf_rec_get_space_func(mtr,rec)
+#else /* UNIV_DEBUG */
+# define ibuf_rec_get_space(mtr,rec) ibuf_rec_get_space_func(rec)
+#endif /* UNIV_DEBUG */
+
+/********************************************************************//**
+Returns the space id field of an ibuf record. For < 4.1.x format records
+returns 0.
+@return	space id */
+static
+ulint
+ibuf_rec_get_space_func(
+/*====================*/
+#ifdef UNIV_DEBUG
+	mtr_t*		mtr,	/*!< in: mini-transaction owning rec */
+#endif /* UNIV_DEBUG */
+	const rec_t*	rec)	/*!< in: ibuf record */
+{
+	const byte*	field;
+	ulint		len;
+
+	ut_ad(mtr_memo_contains_page(mtr, rec, MTR_MEMO_PAGE_X_FIX)
+	      || mtr_memo_contains_page(mtr, rec, MTR_MEMO_PAGE_S_FIX));
+	ut_ad(ibuf_inside(mtr));
+	ut_ad(rec_get_n_fields_old(rec) > 2);
+
+	field = rec_get_nth_field_old(rec, IBUF_REC_FIELD_MARKER, &len);
+
+	ut_a(len == 1);
+
+	field = rec_get_nth_field_old(rec, IBUF_REC_FIELD_SPACE, &len);
+
+	ut_a(len == 4);
+
+	return(mach_read_from_4(field));
+}
+
+#ifdef UNIV_DEBUG
+# define ibuf_rec_get_info(mtr,rec,op,comp,info_len,counter)	\
+	ibuf_rec_get_info_func(mtr,rec,op,comp,info_len,counter)
+#else /* UNIV_DEBUG */
+# define ibuf_rec_get_info(mtr,rec,op,comp,info_len,counter)	\
+	ibuf_rec_get_info_func(rec,op,comp,info_len,counter)
+#endif
+/****************************************************************//**
+Get various information about an ibuf record in >= 4.1.x format. */
+static
+void
+ibuf_rec_get_info_func(
+/*===================*/
+#ifdef UNIV_DEBUG
+	mtr_t*		mtr,	/*!< in: mini-transaction owning rec */
+#endif /* UNIV_DEBUG */
+	const rec_t*	rec,		/*!< in: ibuf record */
+	ibuf_op_t*	op,		/*!< out: operation type, or NULL */
+	ibool*		comp,		/*!< out: compact flag, or NULL */
+	ulint*		info_len,	/*!< out: length of info fields at the
+					start of the fourth field, or
+					NULL */
+	ulint*		counter)	/*!< in: counter value, or NULL */
+{
+	const byte*	types;
+	ulint		fields;
+	ulint		len;
+
+	/* Local variables to shadow arguments. */
+	ibuf_op_t	op_local;
+	ibool		comp_local;
+	ulint		info_len_local;
+	ulint		counter_local;
+
+	ut_ad(mtr_memo_contains_page(mtr, rec, MTR_MEMO_PAGE_X_FIX)
+	      || mtr_memo_contains_page(mtr, rec, MTR_MEMO_PAGE_S_FIX));
+	ut_ad(ibuf_inside(mtr));
+	fields = rec_get_n_fields_old(rec);
+	ut_a(fields > IBUF_REC_FIELD_USER);
+
+	types = rec_get_nth_field_old(rec, IBUF_REC_FIELD_METADATA, &len);
+
+	info_len_local = len % DATA_NEW_ORDER_NULL_TYPE_BUF_SIZE;
+
+	switch (info_len_local) {
+	case 0:
+	case 1:
+		op_local = IBUF_OP_INSERT;
+		comp_local = info_len_local;
+		ut_ad(!counter);
+		counter_local = ULINT_UNDEFINED;
+		break;
+
+	case IBUF_REC_INFO_SIZE:
+		op_local = (ibuf_op_t) types[IBUF_REC_OFFSET_TYPE];
+		comp_local = types[IBUF_REC_OFFSET_FLAGS] & IBUF_REC_COMPACT;
+		counter_local = mach_read_from_2(
+			types + IBUF_REC_OFFSET_COUNTER);
+		break;
+
+	default:
+		ut_error;
+	}
+
+	ut_a(op_local < IBUF_OP_COUNT);
+	ut_a((len - info_len_local) ==
+	     (fields - IBUF_REC_FIELD_USER)
+	     * DATA_NEW_ORDER_NULL_TYPE_BUF_SIZE);
+
+	if (op) {
+		*op = op_local;
+	}
+
+	if (comp) {
+		*comp = comp_local;
+	}
+
+	if (info_len) {
+		*info_len = info_len_local;
+	}
+
+	if (counter) {
+		*counter = counter_local;
+	}
+}
+
+#ifdef UNIV_DEBUG
+# define ibuf_rec_get_op_type(mtr,rec) ibuf_rec_get_op_type_func(mtr,rec)
+#else /* UNIV_DEBUG */
+# define ibuf_rec_get_op_type(mtr,rec) ibuf_rec_get_op_type_func(rec)
+#endif
+
+/****************************************************************//**
+Returns the operation type field of an ibuf record.
+@return	operation type */
+static
+ibuf_op_t
+ibuf_rec_get_op_type_func(
+/*======================*/
+#ifdef UNIV_DEBUG
+	mtr_t*		mtr,	/*!< in: mini-transaction owning rec */
+#endif /* UNIV_DEBUG */
+	const rec_t*	rec)	/*!< in: ibuf record */
+{
+	ulint		len;
+
+	ut_ad(mtr_memo_contains_page(mtr, rec, MTR_MEMO_PAGE_X_FIX)
+	      || mtr_memo_contains_page(mtr, rec, MTR_MEMO_PAGE_S_FIX));
+	ut_ad(ibuf_inside(mtr));
+	ut_ad(rec_get_n_fields_old(rec) > 2);
+
+	(void) rec_get_nth_field_old(rec, IBUF_REC_FIELD_MARKER, &len);
+
+	if (len > 1) {
+		/* This is a < 4.1.x format record */
+
+		return(IBUF_OP_INSERT);
+	} else {
+		ibuf_op_t	op;
+
+		ibuf_rec_get_info(mtr, rec, &op, NULL, NULL, NULL);
+
+		return(op);
+	}
+}
+
+/****************************************************************//**
+Read the first two bytes from a record's fourth field (counter field in new
+records; something else in older records).
+@return "counter" field, or ULINT_UNDEFINED if for some reason it
+can't be read */
+UNIV_INTERN
+ulint
+ibuf_rec_get_counter(
+/*=================*/
+	const rec_t*	rec)	/*!< in: ibuf record */
+{
+	const byte*	ptr;
+	ulint		len;
+
+	if (rec_get_n_fields_old(rec) <= IBUF_REC_FIELD_METADATA) {
+
+		return(ULINT_UNDEFINED);
+	}
+
+	ptr = rec_get_nth_field_old(rec, IBUF_REC_FIELD_METADATA, &len);
+
+	if (len >= 2) {
+
+		return(mach_read_from_2(ptr));
+	} else {
+
+		return(ULINT_UNDEFINED);
+	}
+}
+
+/****************************************************************//**
+Add accumulated operation counts to a permanent array. Both arrays must be
+of size IBUF_OP_COUNT. */
+static
+void
+ibuf_add_ops(
+/*=========*/
+	ulint*		arr,	/*!< in/out: array to modify */
+	const ulint*	ops)	/*!< in: operation counts */
+
+{
+	ulint	i;
+
+#ifndef HAVE_ATOMIC_BUILTINS
+	ut_ad(mutex_own(&ibuf_mutex));
+#endif /* !HAVE_ATOMIC_BUILTINS */
+
+	for (i = 0; i < IBUF_OP_COUNT; i++) {
+#ifdef HAVE_ATOMIC_BUILTINS
+		os_atomic_increment_ulint(&arr[i], ops[i]);
+#else /* HAVE_ATOMIC_BUILTINS */
+		arr[i] += ops[i];
+#endif /* HAVE_ATOMIC_BUILTINS */
+	}
+}
+
+/****************************************************************//**
+Print operation counts. The array must be of size IBUF_OP_COUNT. */
+static
+void
+ibuf_print_ops(
+/*===========*/
+	const ulint*	ops,	/*!< in: operation counts */
+	FILE*		file)	/*!< in: file where to print */
+{
+	static const char* op_names[] = {
+		"insert",
+		"delete mark",
+		"delete"
+	};
+	ulint	i;
+
+	ut_a(UT_ARR_SIZE(op_names) == IBUF_OP_COUNT);
+
+	for (i = 0; i < IBUF_OP_COUNT; i++) {
+		fprintf(file, "%s %lu%s", op_names[i],
+			(ulong) ops[i], (i < (IBUF_OP_COUNT - 1)) ? ", " : "");
+	}
+
+	putc('\n', file);
+}
+
+/********************************************************************//**
+Creates a dummy index for inserting a record to a non-clustered index.
+@return	dummy index */
+static
+dict_index_t*
+ibuf_dummy_index_create(
+/*====================*/
+	ulint		n,	/*!< in: number of fields */
+	ibool		comp)	/*!< in: TRUE=use compact record format */
+{
+	dict_table_t*	table;
+	dict_index_t*	index;
+
+	table = dict_mem_table_create("IBUF_DUMMY",
+				      DICT_HDR_SPACE, n,
+				      comp ? DICT_TF_COMPACT : 0, 0);
+
+	index = dict_mem_index_create("IBUF_DUMMY", "IBUF_DUMMY",
+				      DICT_HDR_SPACE, 0, n);
+
+	index->table = table;
+
+	/* avoid ut_ad(index->cached) in dict_index_get_n_unique_in_tree */
+	index->cached = TRUE;
+
+	return(index);
+}
+/********************************************************************//**
+Add a column to the dummy index */
+static
+void
+ibuf_dummy_index_add_col(
+/*=====================*/
+	dict_index_t*	index,	/*!< in: dummy index */
+	const dtype_t*	type,	/*!< in: the data type of the column */
+	ulint		len)	/*!< in: length of the column */
+{
+	ulint	i	= index->table->n_def;
+	dict_mem_table_add_col(index->table, NULL, NULL,
+			       dtype_get_mtype(type),
+			       dtype_get_prtype(type),
+			       dtype_get_len(type));
+	dict_index_add_col(index, index->table,
+			   dict_table_get_nth_col(index->table, i), len);
+}
+/********************************************************************//**
+Deallocates a dummy index for inserting a record to a non-clustered index. */
+static
+void
+ibuf_dummy_index_free(
+/*==================*/
+	dict_index_t*	index)	/*!< in, own: dummy index */
+{
+	dict_table_t*	table = index->table;
+
+	dict_mem_index_free(index);
+	dict_mem_table_free(table);
+}
+
+#ifdef UNIV_DEBUG
+# define ibuf_build_entry_from_ibuf_rec(mtr,ibuf_rec,heap,pindex)	\
+	ibuf_build_entry_from_ibuf_rec_func(mtr,ibuf_rec,heap,pindex)
+#else /* UNIV_DEBUG */
+# define ibuf_build_entry_from_ibuf_rec(mtr,ibuf_rec,heap,pindex)	\
+	ibuf_build_entry_from_ibuf_rec_func(ibuf_rec,heap,pindex)
+#endif
+
+/*********************************************************************//**
+Builds the entry used to
+
+1) IBUF_OP_INSERT: insert into a non-clustered index
+
+2) IBUF_OP_DELETE_MARK: find the record whose delete-mark flag we need to
+   activate
+
+3) IBUF_OP_DELETE: find the record we need to delete
+
+when we have the corresponding record in an ibuf index.
+
+NOTE that as we copy pointers to fields in ibuf_rec, the caller must
+hold a latch to the ibuf_rec page as long as the entry is used!
+
+@return own: entry to insert to a non-clustered index */
+static
+dtuple_t*
+ibuf_build_entry_from_ibuf_rec_func(
+/*================================*/
+#ifdef UNIV_DEBUG
+	mtr_t*		mtr,	/*!< in: mini-transaction owning rec */
+#endif /* UNIV_DEBUG */
+	const rec_t*	ibuf_rec,	/*!< in: record in an insert buffer */
+	mem_heap_t*	heap,		/*!< in: heap where built */
+	dict_index_t**	pindex)		/*!< out, own: dummy index that
+					describes the entry */
+{
+	dtuple_t*	tuple;
+	dfield_t*	field;
+	ulint		n_fields;
+	const byte*	types;
+	const byte*	data;
+	ulint		len;
+	ulint		info_len;
+	ulint		i;
+	ulint		comp;
+	dict_index_t*	index;
+
+	ut_ad(mtr_memo_contains_page(mtr, ibuf_rec, MTR_MEMO_PAGE_X_FIX)
+	      || mtr_memo_contains_page(mtr, ibuf_rec, MTR_MEMO_PAGE_S_FIX));
+	ut_ad(ibuf_inside(mtr));
+
+	data = rec_get_nth_field_old(ibuf_rec, IBUF_REC_FIELD_MARKER, &len);
+
+	ut_a(len == 1);
+	ut_a(*data == 0);
+	ut_a(rec_get_n_fields_old(ibuf_rec) > IBUF_REC_FIELD_USER);
+
+	n_fields = rec_get_n_fields_old(ibuf_rec) - IBUF_REC_FIELD_USER;
+
+	tuple = dtuple_create(heap, n_fields);
+
+	types = rec_get_nth_field_old(ibuf_rec, IBUF_REC_FIELD_METADATA, &len);
+
+	ibuf_rec_get_info(mtr, ibuf_rec, NULL, &comp, &info_len, NULL);
+
+	index = ibuf_dummy_index_create(n_fields, comp);
+
+	len -= info_len;
+	types += info_len;
+
+	ut_a(len == n_fields * DATA_NEW_ORDER_NULL_TYPE_BUF_SIZE);
+
+	for (i = 0; i < n_fields; i++) {
+		field = dtuple_get_nth_field(tuple, i);
+
+		data = rec_get_nth_field_old(
+			ibuf_rec, i + IBUF_REC_FIELD_USER, &len);
+
+		dfield_set_data(field, data, len);
+
+		dtype_new_read_for_order_and_null_size(
+			dfield_get_type(field),
+			types + i * DATA_NEW_ORDER_NULL_TYPE_BUF_SIZE);
+
+		ibuf_dummy_index_add_col(index, dfield_get_type(field), len);
+	}
+
+	/* Prevent an ut_ad() failure in page_zip_write_rec() by
+	adding system columns to the dummy table pointed to by the
+	dummy secondary index.  The insert buffer is only used for
+	secondary indexes, whose records never contain any system
+	columns, such as DB_TRX_ID. */
+	ut_d(dict_table_add_system_columns(index->table, index->table->heap));
+
+	*pindex = index;
+
+	return(tuple);
+}
+
+/******************************************************************//**
+Get the data size.
+@return	size of fields */
+UNIV_INLINE
+ulint
+ibuf_rec_get_size(
+/*==============*/
+	const rec_t*	rec,			/*!< in: ibuf record */
+	const byte*	types,			/*!< in: fields */
+	ulint		n_fields,		/*!< in: number of fields */
+	ulint		comp)			/*!< in: 0=ROW_FORMAT=REDUNDANT,
+						nonzero=ROW_FORMAT=COMPACT */
+{
+	ulint	i;
+	ulint	field_offset;
+	ulint	types_offset;
+	ulint	size = 0;
+
+	field_offset = IBUF_REC_FIELD_USER;
+	types_offset = DATA_NEW_ORDER_NULL_TYPE_BUF_SIZE;
+
+	for (i = 0; i < n_fields; i++) {
+		ulint		len;
+		dtype_t		dtype;
+
+		rec_get_nth_field_offs_old(rec, i + field_offset, &len);
+
+		if (len != UNIV_SQL_NULL) {
+			size += len;
+		} else {
+			dtype_new_read_for_order_and_null_size(&dtype, types);
+
+			size += dtype_get_sql_null_size(&dtype, comp);
+		}
+
+		types += types_offset;
+	}
+
+	return(size);
+}
+
+#ifdef UNIV_DEBUG
+# define ibuf_rec_get_volume(mtr,rec) ibuf_rec_get_volume_func(mtr,rec)
+#else /* UNIV_DEBUG */
+# define ibuf_rec_get_volume(mtr,rec) ibuf_rec_get_volume_func(rec)
+#endif
+
+/********************************************************************//**
+Returns the space taken by a stored non-clustered index entry if converted to
+an index record.
+@return size of index record in bytes + an upper limit of the space
+taken in the page directory */
+static
+ulint
+ibuf_rec_get_volume_func(
+/*=====================*/
+#ifdef UNIV_DEBUG
+	mtr_t*		mtr,	/*!< in: mini-transaction owning rec */
+#endif /* UNIV_DEBUG */
+	const rec_t*	ibuf_rec)/*!< in: ibuf record */
+{
+	ulint		len;
+	const byte*	data;
+	const byte*	types;
+	ulint		n_fields;
+	ulint		data_size;
+	ulint		comp;
+	ibuf_op_t	op;
+	ulint		info_len;
+
+	ut_ad(mtr_memo_contains_page(mtr, ibuf_rec, MTR_MEMO_PAGE_X_FIX)
+	      || mtr_memo_contains_page(mtr, ibuf_rec, MTR_MEMO_PAGE_S_FIX));
+	ut_ad(ibuf_inside(mtr));
+	ut_ad(rec_get_n_fields_old(ibuf_rec) > 2);
+
+	data = rec_get_nth_field_old(ibuf_rec, IBUF_REC_FIELD_MARKER, &len);
+	ut_a(len == 1);
+	ut_a(*data == 0);
+
+	types = rec_get_nth_field_old(
+		ibuf_rec, IBUF_REC_FIELD_METADATA, &len);
+
+	ibuf_rec_get_info(mtr, ibuf_rec, &op, &comp, &info_len, NULL);
+
+	if (op == IBUF_OP_DELETE_MARK || op == IBUF_OP_DELETE) {
+		/* Delete-marking a record doesn't take any
+		additional space, and while deleting a record
+		actually frees up space, we have to play it safe and
+		pretend it takes no additional space (the record
+		might not exist, etc.).  */
+
+		return(0);
+	} else if (comp) {
+		dtuple_t*	entry;
+		ulint		volume;
+		dict_index_t*	dummy_index;
+		mem_heap_t*	heap = mem_heap_create(500);
+
+		entry = ibuf_build_entry_from_ibuf_rec(mtr, ibuf_rec,
+			heap, &dummy_index);
+
+		volume = rec_get_converted_size(dummy_index, entry, 0);
+
+		ibuf_dummy_index_free(dummy_index);
+		mem_heap_free(heap);
+
+		return(volume + page_dir_calc_reserved_space(1));
+	}
+
+	types += info_len;
+	n_fields = rec_get_n_fields_old(ibuf_rec)
+		- IBUF_REC_FIELD_USER;
+
+	data_size = ibuf_rec_get_size(ibuf_rec, types, n_fields, comp);
+
+	return(data_size + rec_get_converted_extra_size(data_size, n_fields, 0)
+	       + page_dir_calc_reserved_space(1));
+}
+
+/*********************************************************************//**
+Builds the tuple to insert to an ibuf tree when we have an entry for a
+non-clustered index.
+
+NOTE that the original entry must be kept because we copy pointers to
+its fields.
+
+@return	own: entry to insert into an ibuf index tree */
+static
+dtuple_t*
+ibuf_entry_build(
+/*=============*/
+	ibuf_op_t	op,	/*!< in: operation type */
+	dict_index_t*	index,	/*!< in: non-clustered index */
+	const dtuple_t*	entry,	/*!< in: entry for a non-clustered index */
+	ulint		space,	/*!< in: space id */
+	ulint		page_no,/*!< in: index page number where entry should
+				be inserted */
+	ulint		counter,/*!< in: counter value;
+				ULINT_UNDEFINED=not used */
+	mem_heap_t*	heap)	/*!< in: heap into which to build */
+{
+	dtuple_t*	tuple;
+	dfield_t*	field;
+	const dfield_t*	entry_field;
+	ulint		n_fields;
+	byte*		buf;
+	byte*		ti;
+	byte*		type_info;
+	ulint		i;
+
+	ut_ad(counter != ULINT_UNDEFINED || op == IBUF_OP_INSERT);
+	ut_ad(counter == ULINT_UNDEFINED || counter <= 0xFFFF);
+	ut_ad(op < IBUF_OP_COUNT);
+
+	/* We have to build a tuple with the following fields:
+
+	1-4) These are described at the top of this file.
+
+	5) The rest of the fields are copied from the entry.
+
+	All fields in the tuple are ordered like the type binary in our
+	insert buffer tree. */
+
+	n_fields = dtuple_get_n_fields(entry);
+
+	tuple = dtuple_create(heap, n_fields + IBUF_REC_FIELD_USER);
+
+	/* 1) Space Id */
+
+	field = dtuple_get_nth_field(tuple, IBUF_REC_FIELD_SPACE);
+
+	buf = static_cast<byte*>(mem_heap_alloc(heap, 4));
+
+	mach_write_to_4(buf, space);
+
+	dfield_set_data(field, buf, 4);
+
+	/* 2) Marker byte */
+
+	field = dtuple_get_nth_field(tuple, IBUF_REC_FIELD_MARKER);
+
+	buf = static_cast<byte*>(mem_heap_alloc(heap, 1));
+
+	/* We set the marker byte zero */
+
+	mach_write_to_1(buf, 0);
+
+	dfield_set_data(field, buf, 1);
+
+	/* 3) Page number */
+
+	field = dtuple_get_nth_field(tuple, IBUF_REC_FIELD_PAGE);
+
+	buf = static_cast<byte*>(mem_heap_alloc(heap, 4));
+
+	mach_write_to_4(buf, page_no);
+
+	dfield_set_data(field, buf, 4);
+
+	/* 4) Type info, part #1 */
+
+	if (counter == ULINT_UNDEFINED) {
+		i = dict_table_is_comp(index->table) ? 1 : 0;
+	} else {
+		ut_ad(counter <= 0xFFFF);
+		i = IBUF_REC_INFO_SIZE;
+	}
+
+	ti = type_info = static_cast<byte*>(
+		mem_heap_alloc(
+			heap,
+			i + n_fields * DATA_NEW_ORDER_NULL_TYPE_BUF_SIZE));
+
+	switch (i) {
+	default:
+		ut_error;
+		break;
+	case 1:
+		/* set the flag for ROW_FORMAT=COMPACT */
+		*ti++ = 0;
+		/* fall through */
+	case 0:
+		/* the old format does not allow delete buffering */
+		ut_ad(op == IBUF_OP_INSERT);
+		break;
+	case IBUF_REC_INFO_SIZE:
+		mach_write_to_2(ti + IBUF_REC_OFFSET_COUNTER, counter);
+
+		ti[IBUF_REC_OFFSET_TYPE] = (byte) op;
+		ti[IBUF_REC_OFFSET_FLAGS] = dict_table_is_comp(index->table)
+			? IBUF_REC_COMPACT : 0;
+		ti += IBUF_REC_INFO_SIZE;
+		break;
+	}
+
+	/* 5+) Fields from the entry */
+
+	for (i = 0; i < n_fields; i++) {
+		ulint			fixed_len;
+		const dict_field_t*	ifield;
+
+		field = dtuple_get_nth_field(tuple, i + IBUF_REC_FIELD_USER);
+		entry_field = dtuple_get_nth_field(entry, i);
+		dfield_copy(field, entry_field);
+
+		ifield = dict_index_get_nth_field(index, i);
+		/* Prefix index columns of fixed-length columns are of
+		fixed length.  However, in the function call below,
+		dfield_get_type(entry_field) contains the fixed length
+		of the column in the clustered index.  Replace it with
+		the fixed length of the secondary index column. */
+		fixed_len = ifield->fixed_len;
+
+#ifdef UNIV_DEBUG
+		if (fixed_len) {
+			/* dict_index_add_col() should guarantee these */
+			ut_ad(fixed_len <= (ulint)
+			      dfield_get_type(entry_field)->len);
+			if (ifield->prefix_len) {
+				ut_ad(ifield->prefix_len == fixed_len);
+			} else {
+				ut_ad(fixed_len == (ulint)
+				      dfield_get_type(entry_field)->len);
+			}
+		}
+#endif /* UNIV_DEBUG */
+
+		dtype_new_store_for_order_and_null_size(
+			ti, dfield_get_type(entry_field), fixed_len);
+		ti += DATA_NEW_ORDER_NULL_TYPE_BUF_SIZE;
+	}
+
+	/* 4) Type info, part #2 */
+
+	field = dtuple_get_nth_field(tuple, IBUF_REC_FIELD_METADATA);
+
+	dfield_set_data(field, type_info, ti - type_info);
+
+	/* Set all the types in the new tuple binary */
+
+	dtuple_set_types_binary(tuple, n_fields + IBUF_REC_FIELD_USER);
+
+	return(tuple);
+}
+
+/*********************************************************************//**
+Builds a search tuple used to search buffered inserts for an index page.
+This is for >= 4.1.x format records.
+@return	own: search tuple */
+static
+dtuple_t*
+ibuf_search_tuple_build(
+/*====================*/
+	ulint		space,	/*!< in: space id */
+	ulint		page_no,/*!< in: index page number */
+	mem_heap_t*	heap)	/*!< in: heap into which to build */
+{
+	dtuple_t*	tuple;
+	dfield_t*	field;
+	byte*		buf;
+
+	tuple = dtuple_create(heap, IBUF_REC_FIELD_METADATA);
+
+	/* Store the space id in tuple */
+
+	field = dtuple_get_nth_field(tuple, IBUF_REC_FIELD_SPACE);
+
+	buf = static_cast<byte*>(mem_heap_alloc(heap, 4));
+
+	mach_write_to_4(buf, space);
+
+	dfield_set_data(field, buf, 4);
+
+	/* Store the new format record marker byte */
+
+	field = dtuple_get_nth_field(tuple, IBUF_REC_FIELD_MARKER);
+
+	buf = static_cast<byte*>(mem_heap_alloc(heap, 1));
+
+	mach_write_to_1(buf, 0);
+
+	dfield_set_data(field, buf, 1);
+
+	/* Store the page number in tuple */
+
+	field = dtuple_get_nth_field(tuple, IBUF_REC_FIELD_PAGE);
+
+	buf = static_cast<byte*>(mem_heap_alloc(heap, 4));
+
+	mach_write_to_4(buf, page_no);
+
+	dfield_set_data(field, buf, 4);
+
+	dtuple_set_types_binary(tuple, IBUF_REC_FIELD_METADATA);
+
+	return(tuple);
+}
+
+/*********************************************************************//**
+Checks if there are enough pages in the free list of the ibuf tree that we
+dare to start a pessimistic insert to the insert buffer.
+@return	TRUE if enough free pages in list */
+UNIV_INLINE
+ibool
+ibuf_data_enough_free_for_insert(void)
+/*==================================*/
+{
+	ut_ad(mutex_own(&ibuf_mutex));
+
+	/* We want a big margin of free pages, because a B-tree can sometimes
+	grow in size also if records are deleted from it, as the node pointers
+	can change, and we must make sure that we are able to delete the
+	inserts buffered for pages that we read to the buffer pool, without
+	any risk of running out of free space in the insert buffer. */
+
+	return(ibuf->free_list_len >= (ibuf->size / 2) + 3 * ibuf->height);
+}
+
+/*********************************************************************//**
+Checks if there are enough pages in the free list of the ibuf tree that we
+should remove them and free to the file space management.
+@return	TRUE if enough free pages in list */
+UNIV_INLINE
+ibool
+ibuf_data_too_much_free(void)
+/*=========================*/
+{
+	ut_ad(mutex_own(&ibuf_mutex));
+
+	return(ibuf->free_list_len >= 3 + (ibuf->size / 2) + 3 * ibuf->height);
+}
+
+/*********************************************************************//**
+Allocates a new page from the ibuf file segment and adds it to the free
+list.
+@return	TRUE on success, FALSE if no space left */
+static
+ibool
+ibuf_add_free_page(void)
+/*====================*/
+{
+	mtr_t		mtr;
+	page_t*		header_page;
+	ulint		flags;
+	ulint		zip_size;
+	buf_block_t*	block;
+	page_t*		page;
+	page_t*		root;
+	page_t*		bitmap_page;
+
+	mtr_start(&mtr);
+
+	/* Acquire the fsp latch before the ibuf header, obeying the latching
+	order */
+	mtr_x_lock(fil_space_get_latch(IBUF_SPACE_ID, &flags), &mtr);
+	zip_size = fsp_flags_get_zip_size(flags);
+
+	header_page = ibuf_header_page_get(&mtr);
+
+	/* Allocate a new page: NOTE that if the page has been a part of a
+	non-clustered index which has subsequently been dropped, then the
+	page may have buffered inserts in the insert buffer, and these
+	should be deleted from there. These get deleted when the page
+	allocation creates the page in buffer. Thus the call below may end
+	up calling the insert buffer routines and, as we yet have no latches
+	to insert buffer tree pages, these routines can run without a risk
+	of a deadlock. This is the reason why we created a special ibuf
+	header page apart from the ibuf tree. */
+
+	block = fseg_alloc_free_page(
+		header_page + IBUF_HEADER + IBUF_TREE_SEG_HEADER, 0, FSP_UP,
+		&mtr);
+
+	if (block == NULL) {
+		mtr_commit(&mtr);
+
+		return(FALSE);
+	}
+
+	ut_ad(rw_lock_get_x_lock_count(&block->lock) == 1);
+	ibuf_enter(&mtr);
+	mutex_enter(&ibuf_mutex);
+	root = ibuf_tree_root_get(&mtr);
+
+	buf_block_dbg_add_level(block, SYNC_IBUF_TREE_NODE_NEW);
+	page = buf_block_get_frame(block);
+
+	/* Add the page to the free list and update the ibuf size data */
+
+	flst_add_last(root + PAGE_HEADER + PAGE_BTR_IBUF_FREE_LIST,
+		      page + PAGE_HEADER + PAGE_BTR_IBUF_FREE_LIST_NODE, &mtr);
+
+	mlog_write_ulint(page + FIL_PAGE_TYPE, FIL_PAGE_IBUF_FREE_LIST,
+			 MLOG_2BYTES, &mtr);
+
+	ibuf->seg_size++;
+	ibuf->free_list_len++;
+
+	/* Set the bit indicating that this page is now an ibuf tree page
+	(level 2 page) */
+
+	bitmap_page = ibuf_bitmap_get_map_page(
+		IBUF_SPACE_ID, buf_block_get_page_no(block), zip_size, &mtr);
+
+	mutex_exit(&ibuf_mutex);
+
+	ibuf_bitmap_page_set_bits(
+		bitmap_page, buf_block_get_page_no(block), zip_size,
+		IBUF_BITMAP_IBUF, TRUE, &mtr);
+
+	ibuf_mtr_commit(&mtr);
+
+	return(TRUE);
+}
+
+/*********************************************************************//**
+Removes a page from the free list and frees it to the fsp system. */
+static
+void
+ibuf_remove_free_page(void)
+/*=======================*/
+{
+	mtr_t	mtr;
+	mtr_t	mtr2;
+	page_t*	header_page;
+	ulint	flags;
+	ulint	zip_size;
+	ulint	page_no;
+	page_t*	page;
+	page_t*	root;
+	page_t*	bitmap_page;
+
+	mtr_start(&mtr);
+
+	/* Acquire the fsp latch before the ibuf header, obeying the latching
+	order */
+	mtr_x_lock(fil_space_get_latch(IBUF_SPACE_ID, &flags), &mtr);
+	zip_size = fsp_flags_get_zip_size(flags);
+
+	header_page = ibuf_header_page_get(&mtr);
+
+	/* Prevent pessimistic inserts to insert buffer trees for a while */
+	ibuf_enter(&mtr);
+	mutex_enter(&ibuf_pessimistic_insert_mutex);
+	mutex_enter(&ibuf_mutex);
+
+	if (!ibuf_data_too_much_free()) {
+
+		mutex_exit(&ibuf_mutex);
+		mutex_exit(&ibuf_pessimistic_insert_mutex);
+
+		ibuf_mtr_commit(&mtr);
+
+		return;
+	}
+
+	ibuf_mtr_start(&mtr2);
+
+	root = ibuf_tree_root_get(&mtr2);
+
+	mutex_exit(&ibuf_mutex);
+
+	page_no = flst_get_last(root + PAGE_HEADER + PAGE_BTR_IBUF_FREE_LIST,
+				&mtr2).page;
+
+	/* NOTE that we must release the latch on the ibuf tree root
+	because in fseg_free_page we access level 1 pages, and the root
+	is a level 2 page. */
+
+	ibuf_mtr_commit(&mtr2);
+	ibuf_exit(&mtr);
+
+	/* Since pessimistic inserts were prevented, we know that the
+	page is still in the free list. NOTE that also deletes may take
+	pages from the free list, but they take them from the start, and
+	the free list was so long that they cannot have taken the last
+	page from it. */
+
+	fseg_free_page(header_page + IBUF_HEADER + IBUF_TREE_SEG_HEADER,
+		       IBUF_SPACE_ID, page_no, &mtr);
+
+#if defined UNIV_DEBUG_FILE_ACCESSES || defined UNIV_DEBUG
+	buf_page_reset_file_page_was_freed(IBUF_SPACE_ID, page_no);
+#endif /* UNIV_DEBUG_FILE_ACCESSES || UNIV_DEBUG */
+
+	ibuf_enter(&mtr);
+
+	mutex_enter(&ibuf_mutex);
+
+	root = ibuf_tree_root_get(&mtr);
+
+	ut_ad(page_no == flst_get_last(root + PAGE_HEADER
+				       + PAGE_BTR_IBUF_FREE_LIST, &mtr).page);
+
+	{
+		buf_block_t*	block;
+
+		block = buf_page_get(
+			IBUF_SPACE_ID, 0, page_no, RW_X_LATCH, &mtr);
+
+		buf_block_dbg_add_level(block, SYNC_IBUF_TREE_NODE);
+
+		page = buf_block_get_frame(block);
+	}
+
+	/* Remove the page from the free list and update the ibuf size data */
+
+	flst_remove(root + PAGE_HEADER + PAGE_BTR_IBUF_FREE_LIST,
+		    page + PAGE_HEADER + PAGE_BTR_IBUF_FREE_LIST_NODE, &mtr);
+
+	mutex_exit(&ibuf_pessimistic_insert_mutex);
+
+	ibuf->seg_size--;
+	ibuf->free_list_len--;
+
+	/* Set the bit indicating that this page is no more an ibuf tree page
+	(level 2 page) */
+
+	bitmap_page = ibuf_bitmap_get_map_page(
+		IBUF_SPACE_ID, page_no, zip_size, &mtr);
+
+	mutex_exit(&ibuf_mutex);
+
+	ibuf_bitmap_page_set_bits(
+		bitmap_page, page_no, zip_size, IBUF_BITMAP_IBUF, FALSE, &mtr);
+
+#if defined UNIV_DEBUG_FILE_ACCESSES || defined UNIV_DEBUG
+	buf_page_set_file_page_was_freed(IBUF_SPACE_ID, page_no);
+#endif /* UNIV_DEBUG_FILE_ACCESSES || UNIV_DEBUG */
+	ibuf_mtr_commit(&mtr);
+}
+
+/***********************************************************************//**
+Frees excess pages from the ibuf free list. This function is called when an OS
+thread calls fsp services to allocate a new file segment, or a new page to a
+file segment, and the thread did not own the fsp latch before this call. */
+UNIV_INTERN
+void
+ibuf_free_excess_pages(void)
+/*========================*/
+{
+	ulint		i;
+
+#ifdef UNIV_SYNC_DEBUG
+	ut_ad(rw_lock_own(fil_space_get_latch(IBUF_SPACE_ID, NULL),
+			  RW_LOCK_EX));
+#endif /* UNIV_SYNC_DEBUG */
+
+	ut_ad(rw_lock_get_x_lock_count(
+		fil_space_get_latch(IBUF_SPACE_ID, NULL)) == 1);
+
+	/* NOTE: We require that the thread did not own the latch before,
+	because then we know that we can obey the correct latching order
+	for ibuf latches */
+
+	if (!ibuf) {
+		/* Not yet initialized; not sure if this is possible, but
+		does no harm to check for it. */
+
+		return;
+	}
+
+	/* Free at most a few pages at a time, so that we do not delay the
+	requested service too much */
+
+	for (i = 0; i < 4; i++) {
+
+		ibool	too_much_free;
+
+		mutex_enter(&ibuf_mutex);
+		too_much_free = ibuf_data_too_much_free();
+		mutex_exit(&ibuf_mutex);
+
+		if (!too_much_free) {
+			return;
+		}
+
+		ibuf_remove_free_page();
+	}
+}
+
+#ifdef UNIV_DEBUG
+# define ibuf_get_merge_page_nos(contract,rec,mtr,ids,vers,pages,n_stored) \
+	ibuf_get_merge_page_nos_func(contract,rec,mtr,ids,vers,pages,n_stored)
+#else /* UNIV_DEBUG */
+# define ibuf_get_merge_page_nos(contract,rec,mtr,ids,vers,pages,n_stored) \
+	ibuf_get_merge_page_nos_func(contract,rec,ids,vers,pages,n_stored)
+#endif /* UNIV_DEBUG */
+
+/*********************************************************************//**
+Reads page numbers from a leaf in an ibuf tree.
+@return a lower limit for the combined volume of records which will be
+merged */
+static
+ulint
+ibuf_get_merge_page_nos_func(
+/*=========================*/
+	ibool		contract,/*!< in: TRUE if this function is called to
+				contract the tree, FALSE if this is called
+				when a single page becomes full and we look
+				if it pays to read also nearby pages */
+	const rec_t*	rec,	/*!< in: insert buffer record */
+#ifdef UNIV_DEBUG
+	mtr_t*		mtr,	/*!< in: mini-transaction holding rec */
+#endif /* UNIV_DEBUG */
+	ulint*		space_ids,/*!< in/out: space id's of the pages */
+	ib_int64_t*	space_versions,/*!< in/out: tablespace version
+				timestamps; used to prevent reading in old
+				pages after DISCARD + IMPORT tablespace */
+	ulint*		page_nos,/*!< in/out: buffer for at least
+				IBUF_MAX_N_PAGES_MERGED many page numbers;
+				the page numbers are in an ascending order */
+	ulint*		n_stored)/*!< out: number of page numbers stored to
+				page_nos in this function */
+{
+	ulint	prev_page_no;
+	ulint	prev_space_id;
+	ulint	first_page_no;
+	ulint	first_space_id;
+	ulint	rec_page_no;
+	ulint	rec_space_id;
+	ulint	sum_volumes;
+	ulint	volume_for_page;
+	ulint	rec_volume;
+	ulint	limit;
+	ulint	n_pages;
+
+	ut_ad(mtr_memo_contains_page(mtr, rec, MTR_MEMO_PAGE_X_FIX)
+	      || mtr_memo_contains_page(mtr, rec, MTR_MEMO_PAGE_S_FIX));
+	ut_ad(ibuf_inside(mtr));
+
+	*n_stored = 0;
+
+	limit = ut_min(IBUF_MAX_N_PAGES_MERGED, buf_pool_get_curr_size() / 4);
+
+	if (page_rec_is_supremum(rec)) {
+
+		rec = page_rec_get_prev_const(rec);
+	}
+
+	if (page_rec_is_infimum(rec)) {
+
+		rec = page_rec_get_next_const(rec);
+	}
+
+	if (page_rec_is_supremum(rec)) {
+
+		return(0);
+	}
+
+	first_page_no = ibuf_rec_get_page_no(mtr, rec);
+	first_space_id = ibuf_rec_get_space(mtr, rec);
+	n_pages = 0;
+	prev_page_no = 0;
+	prev_space_id = 0;
+
+	/* Go backwards from the first rec until we reach the border of the
+	'merge area', or the page start or the limit of storeable pages is
+	reached */
+
+	while (!page_rec_is_infimum(rec) && UNIV_LIKELY(n_pages < limit)) {
+
+		rec_page_no = ibuf_rec_get_page_no(mtr, rec);
+		rec_space_id = ibuf_rec_get_space(mtr, rec);
+
+		if (rec_space_id != first_space_id
+		    || (rec_page_no / IBUF_MERGE_AREA)
+		    != (first_page_no / IBUF_MERGE_AREA)) {
+
+			break;
+		}
+
+		if (rec_page_no != prev_page_no
+		    || rec_space_id != prev_space_id) {
+			n_pages++;
+		}
+
+		prev_page_no = rec_page_no;
+		prev_space_id = rec_space_id;
+
+		rec = page_rec_get_prev_const(rec);
+	}
+
+	rec = page_rec_get_next_const(rec);
+
+	/* At the loop start there is no prev page; we mark this with a pair
+	of space id, page no (0, 0) for which there can never be entries in
+	the insert buffer */
+
+	prev_page_no = 0;
+	prev_space_id = 0;
+	sum_volumes = 0;
+	volume_for_page = 0;
+
+	while (*n_stored < limit) {
+		if (page_rec_is_supremum(rec)) {
+			/* When no more records available, mark this with
+			another 'impossible' pair of space id, page no */
+			rec_page_no = 1;
+			rec_space_id = 0;
+		} else {
+			rec_page_no = ibuf_rec_get_page_no(mtr, rec);
+			rec_space_id = ibuf_rec_get_space(mtr, rec);
+			/* In the system tablespace, the smallest
+			possible secondary index leaf page number is
+			bigger than IBUF_TREE_ROOT_PAGE_NO (4). In
+			other tablespaces, the clustered index tree is
+			created at page 3, which makes page 4 the
+			smallest possible secondary index leaf page
+			(and that only after DROP INDEX). */
+			ut_ad(rec_page_no
+			      > (ulint) IBUF_TREE_ROOT_PAGE_NO
+			      - (rec_space_id != 0));
+		}
+
+#ifdef UNIV_IBUF_DEBUG
+		ut_a(*n_stored < IBUF_MAX_N_PAGES_MERGED);
+#endif
+		if ((rec_space_id != prev_space_id
+		     || rec_page_no != prev_page_no)
+		    && (prev_space_id != 0 || prev_page_no != 0)) {
+
+			if (contract
+			    || (prev_page_no == first_page_no
+				&& prev_space_id == first_space_id)
+			    || (volume_for_page
+				> ((IBUF_MERGE_THRESHOLD - 1)
+				   * 4 * UNIV_PAGE_SIZE
+				   / IBUF_PAGE_SIZE_PER_FREE_SPACE)
+				/ IBUF_MERGE_THRESHOLD)) {
+
+				space_ids[*n_stored] = prev_space_id;
+				space_versions[*n_stored]
+					= fil_space_get_version(prev_space_id);
+				page_nos[*n_stored] = prev_page_no;
+
+				(*n_stored)++;
+
+				sum_volumes += volume_for_page;
+			}
+
+			if (rec_space_id != first_space_id
+			    || rec_page_no / IBUF_MERGE_AREA
+			    != first_page_no / IBUF_MERGE_AREA) {
+
+				break;
+			}
+
+			volume_for_page = 0;
+		}
+
+		if (rec_page_no == 1 && rec_space_id == 0) {
+			/* Supremum record */
+
+			break;
+		}
+
+		rec_volume = ibuf_rec_get_volume(mtr, rec);
+
+		volume_for_page += rec_volume;
+
+		prev_page_no = rec_page_no;
+		prev_space_id = rec_space_id;
+
+		rec = page_rec_get_next_const(rec);
+	}
+
+#ifdef UNIV_IBUF_DEBUG
+	ut_a(*n_stored <= IBUF_MAX_N_PAGES_MERGED);
+#endif
+#if 0
+	fprintf(stderr, "Ibuf merge batch %lu pages %lu volume\n",
+		*n_stored, sum_volumes);
+#endif
+	return(sum_volumes);
+}
+
+/*******************************************************************//**
+Get the matching records for space id.
+@return	current rec or NULL */
+static	__attribute__((nonnull, warn_unused_result))
+const rec_t*
+ibuf_get_user_rec(
+/*===============*/
+	btr_pcur_t*	pcur,		/*!< in: the current cursor */
+	mtr_t*		mtr)		/*!< in: mini transaction */
+{
+	do {
+		const rec_t* rec = btr_pcur_get_rec(pcur);
+
+		if (page_rec_is_user_rec(rec)) {
+			return(rec);
+		}
+	} while (btr_pcur_move_to_next(pcur, mtr));
+
+	return(NULL);
+}
+
+/*********************************************************************//**
+Reads page numbers for a space id from an ibuf tree.
+@return a lower limit for the combined volume of records which will be
+merged */
+static	__attribute__((nonnull, warn_unused_result))
+ulint
+ibuf_get_merge_pages(
+/*=================*/
+	btr_pcur_t*	pcur,	/*!< in/out: cursor */
+	ulint		space,	/*!< in: space for which to merge */
+	ulint		limit,	/*!< in: max page numbers to read */
+	ulint*		pages,	/*!< out: pages read */
+	ulint*		spaces,	/*!< out: spaces read */
+	ib_int64_t*	versions,/*!< out: space versions read */
+	ulint*		n_pages,/*!< out: number of pages read */
+	mtr_t*		mtr)	/*!< in: mini transaction */
+{
+	const rec_t*	rec;
+	ulint		volume = 0;
+	ib_int64_t	version = fil_space_get_version(space);
+
+	ut_a(space != ULINT_UNDEFINED);
+
+	*n_pages = 0;
+
+	while ((rec = ibuf_get_user_rec(pcur, mtr)) != 0
+	       && ibuf_rec_get_space(mtr, rec) == space
+	       && *n_pages < limit) {
+
+		ulint	page_no = ibuf_rec_get_page_no(mtr, rec);
+
+		if (*n_pages == 0 || pages[*n_pages - 1] != page_no) {
+			spaces[*n_pages] = space;
+			pages[*n_pages] = page_no;
+			versions[*n_pages] = version;
+			++*n_pages;
+		}
+
+		volume += ibuf_rec_get_volume(mtr, rec);
+
+		btr_pcur_move_to_next(pcur, mtr);
+	}
+
+	return(volume);
+}
+
+/*********************************************************************//**
+Contracts insert buffer trees by reading pages to the buffer pool.
+@return a lower limit for the combined size in bytes of entries which
+will be merged from ibuf trees to the pages read, 0 if ibuf is
+empty */
+static
+ulint
+ibuf_merge_pages(
+/*=============*/
+	ulint*	n_pages,	/*!< out: number of pages to which merged */
+	bool	sync)		/*!< in: true if the caller wants to wait for
+				the issued read with the highest tablespace
+				address to complete */
+{
+	mtr_t		mtr;
+	btr_pcur_t	pcur;
+	ulint		sum_sizes;
+	ulint		page_nos[IBUF_MAX_N_PAGES_MERGED];
+	ulint		space_ids[IBUF_MAX_N_PAGES_MERGED];
+	ib_int64_t	space_versions[IBUF_MAX_N_PAGES_MERGED];
+
+	*n_pages = 0;
+
+	ibuf_mtr_start(&mtr);
+
+	/* Open a cursor to a randomly chosen leaf of the tree, at a random
+	position within the leaf */
+
+	btr_pcur_open_at_rnd_pos(ibuf->index, BTR_SEARCH_LEAF, &pcur, &mtr);
+
+	ut_ad(page_validate(btr_pcur_get_page(&pcur), ibuf->index));
+
+	if (page_is_empty(btr_pcur_get_page(&pcur))) {
+		/* If a B-tree page is empty, it must be the root page
+		and the whole B-tree must be empty. InnoDB does not
+		allow empty B-tree pages other than the root. */
+		ut_ad(ibuf->empty);
+		ut_ad(page_get_space_id(btr_pcur_get_page(&pcur))
+		      == IBUF_SPACE_ID);
+		ut_ad(page_get_page_no(btr_pcur_get_page(&pcur))
+		      == FSP_IBUF_TREE_ROOT_PAGE_NO);
+
+		ibuf_mtr_commit(&mtr);
+		btr_pcur_close(&pcur);
+
+		return(0);
+	}
+
+	sum_sizes = ibuf_get_merge_page_nos(TRUE,
+					    btr_pcur_get_rec(&pcur), &mtr,
+					    space_ids, space_versions,
+					    page_nos, n_pages);
+#if 0 /* defined UNIV_IBUF_DEBUG */
+	fprintf(stderr, "Ibuf contract sync %lu pages %lu volume %lu\n",
+		sync, *n_pages, sum_sizes);
+#endif
+	ibuf_mtr_commit(&mtr);
+	btr_pcur_close(&pcur);
+
+	buf_read_ibuf_merge_pages(
+		sync, space_ids, space_versions, page_nos, *n_pages);
+
+	return(sum_sizes + 1);
+}
+
+/*********************************************************************//**
+Get the table instance from the table id.
+@return table instance */
+static __attribute__((warn_unused_result))
+dict_table_t*
+ibuf_get_table(
+/*===========*/
+	table_id_t	table_id)	/*!< in: valid table id */
+{
+	rw_lock_s_lock_func(&dict_operation_lock, 0, __FILE__, __LINE__);
+
+	dict_table_t*	table = dict_table_open_on_id(
+		table_id, FALSE, DICT_TABLE_OP_NORMAL);
+
+	rw_lock_s_unlock_gen(&dict_operation_lock, 0);
+
+	return(table);
+}
+
+/*********************************************************************//**
+Contracts insert buffer trees by reading pages to the buffer pool.
+@return a lower limit for the combined size in bytes of entries which
+will be merged from ibuf trees to the pages read, 0 if ibuf is
+empty */
+static
+ulint
+ibuf_merge_space(
+/*=============*/
+	ulint		space,	/*!< in: tablespace id to merge */
+	ulint*		n_pages)/*!< out: number of pages to which merged */
+{
+	mtr_t		mtr;
+	btr_pcur_t	pcur;
+	mem_heap_t*	heap = mem_heap_create(512);
+	dtuple_t*	tuple = ibuf_search_tuple_build(space, 0, heap);
+
+	ibuf_mtr_start(&mtr);
+
+	/* Position the cursor on the first matching record. */
+
+	btr_pcur_open(
+		ibuf->index, tuple, PAGE_CUR_GE, BTR_SEARCH_LEAF, &pcur,
+		&mtr);
+
+	mem_heap_free(heap);
+
+	ut_ad(page_validate(btr_pcur_get_page(&pcur), ibuf->index));
+
+	ulint		sum_sizes = 0;
+	ulint		pages[IBUF_MAX_N_PAGES_MERGED];
+	ulint		spaces[IBUF_MAX_N_PAGES_MERGED];
+	ib_int64_t	versions[IBUF_MAX_N_PAGES_MERGED];
+
+	if (page_is_empty(btr_pcur_get_page(&pcur))) {
+		/* If a B-tree page is empty, it must be the root page
+		and the whole B-tree must be empty. InnoDB does not
+		allow empty B-tree pages other than the root. */
+		ut_ad(ibuf->empty);
+		ut_ad(page_get_space_id(btr_pcur_get_page(&pcur))
+		      == IBUF_SPACE_ID);
+		ut_ad(page_get_page_no(btr_pcur_get_page(&pcur))
+		      == FSP_IBUF_TREE_ROOT_PAGE_NO);
+
+	} else {
+
+		sum_sizes = ibuf_get_merge_pages(
+			&pcur, space, IBUF_MAX_N_PAGES_MERGED,
+			&pages[0], &spaces[0], &versions[0], n_pages,
+			&mtr);
+
+		++sum_sizes;
+	}
+
+	ibuf_mtr_commit(&mtr);
+
+	btr_pcur_close(&pcur);
+
+	if (sum_sizes > 0) {
+
+		ut_a(*n_pages > 0 || sum_sizes == 1);
+
+#ifdef UNIV_DEBUG
+		ut_ad(*n_pages <= UT_ARR_SIZE(pages));
+
+		for (ulint i = 0; i < *n_pages; ++i) {
+			ut_ad(spaces[i] == space);
+			ut_ad(i == 0 || versions[i] == versions[i - 1]);
+		}
+#endif /* UNIV_DEBUG */
+
+		buf_read_ibuf_merge_pages(
+			true, spaces, versions, pages, *n_pages);
+	}
+
+	return(sum_sizes);
+}
+
+/*********************************************************************//**
+Contracts insert buffer trees by reading pages to the buffer pool.
+@return a lower limit for the combined size in bytes of entries which
+will be merged from ibuf trees to the pages read, 0 if ibuf is
+empty */
+static __attribute__((nonnull, warn_unused_result))
+ulint
+ibuf_merge(
+/*=======*/
+	table_id_t	table_id,	/*!< in: if merge should be
+					done only for a specific
+					table, for all tables this
+					should be 0 */
+	ulint*		n_pages,	/*!< out: number of pages to
+					which merged */
+	bool		sync)		/*!< in: TRUE if the caller
+					wants to wait for the issued
+					read with the highest
+					tablespace address to complete */
+{
+	dict_table_t*	table;
+
+	*n_pages = 0;
+
+	/* We perform a dirty read of ibuf->empty, without latching
+	the insert buffer root page. We trust this dirty read except
+	when a slow shutdown is being executed. During a slow
+	shutdown, the insert buffer merge must be completed. */
+
+	if (ibuf->empty && !srv_shutdown_state) {
+		return(0);
+#if defined UNIV_DEBUG || defined UNIV_IBUF_DEBUG
+	} else if (ibuf_debug) {
+		return(0);
+#endif /* UNIV_DEBUG || UNIV_IBUF_DEBUG */
+	} else if (table_id == 0) {
+		return(ibuf_merge_pages(n_pages, sync));
+	} else if ((table = ibuf_get_table(table_id)) == 0) {
+		/* Table has been dropped. */
+		return(0);
+	}
+
+	ulint	volume = ibuf_merge_space(table->space, n_pages);
+
+	dict_table_close(table, FALSE, FALSE);
+
+	return(volume);
+}
+
+/*********************************************************************//**
+Contracts insert buffer trees by reading pages to the buffer pool.
+@return a lower limit for the combined size in bytes of entries which
+will be merged from ibuf trees to the pages read, 0 if ibuf is
+empty */
+static
+ulint
+ibuf_contract(
+/*==========*/
+	ibool	sync)	/*!< in: TRUE if the caller wants to wait for the
+			issued read with the highest tablespace address
+			to complete */
+{
+	ulint	n_pages;
+
+	return(ibuf_merge(0, &n_pages, sync));
+}
+
+/*********************************************************************//**
+Contracts insert buffer trees by reading pages to the buffer pool.
+@return a lower limit for the combined size in bytes of entries which
+will be merged from ibuf trees to the pages read, 0 if ibuf is
+empty */
+UNIV_INTERN
+ulint
+ibuf_contract_in_background(
+/*========================*/
+	table_id_t	table_id,	/*!< in: if merge should be done only
+					for a specific table, for all tables
+					this should be 0 */
+	ibool		full)		/*!< in: TRUE if the caller wants to
+					do a full contract based on PCT_IO(100).
+					If FALSE then the size of contract
+					batch is determined based on the
+					current size of the ibuf tree. */
+{
+	ulint	sum_bytes	= 0;
+	ulint	sum_pages	= 0;
+	ulint	n_pag2;
+	ulint	n_pages;
+
+#if defined UNIV_DEBUG || defined UNIV_IBUF_DEBUG
+	if (srv_ibuf_disable_background_merge && table_id == 0) {
+		return(0);
+	}
+#endif /* UNIV_DEBUG || UNIV_IBUF_DEBUG */
+
+	if (full) {
+		/* Caller has requested a full batch */
+		n_pages = PCT_IO(100);
+	} else {
+		/* By default we do a batch of 5% of the io_capacity */
+		n_pages = PCT_IO(5);
+
+		mutex_enter(&ibuf_mutex);
+
+		/* If the ibuf->size is more than half the max_size
+		then we make more agreesive contraction.
+		+1 is to avoid division by zero. */
+		if (ibuf->size > ibuf->max_size / 2) {
+			ulint diff = ibuf->size - ibuf->max_size / 2;
+			n_pages += PCT_IO((diff * 100)
+					   / (ibuf->max_size + 1));
+		}
+
+		mutex_exit(&ibuf_mutex);
+	}
+
+	while (sum_pages < n_pages) {
+		ulint	n_bytes;
+
+		n_bytes = ibuf_merge(table_id, &n_pag2, FALSE);
+
+		if (n_bytes == 0) {
+			return(sum_bytes);
+		}
+
+		sum_bytes += n_bytes;
+		sum_pages += n_pag2;
+	}
+
+	return(sum_bytes);
+}
+
+/*********************************************************************//**
+Contract insert buffer trees after insert if they are too big. */
+UNIV_INLINE
+void
+ibuf_contract_after_insert(
+/*=======================*/
+	ulint	entry_size)	/*!< in: size of a record which was inserted
+				into an ibuf tree */
+{
+	ibool	sync;
+	ulint	sum_sizes;
+	ulint	size;
+	ulint	max_size;
+
+	/* Perform dirty reads of ibuf->size and ibuf->max_size, to
+	reduce ibuf_mutex contention. ibuf->max_size remains constant
+	after ibuf_init_at_db_start(), but ibuf->size should be
+	protected by ibuf_mutex. Given that ibuf->size fits in a
+	machine word, this should be OK; at worst we are doing some
+	excessive ibuf_contract() or occasionally skipping a
+	ibuf_contract(). */
+	size = ibuf->size;
+	max_size = ibuf->max_size;
+
+	if (size < max_size + IBUF_CONTRACT_ON_INSERT_NON_SYNC) {
+		return;
+	}
+
+	sync = (size >= max_size + IBUF_CONTRACT_ON_INSERT_SYNC);
+
+	/* Contract at least entry_size many bytes */
+	sum_sizes = 0;
+	size = 1;
+
+	do {
+
+		size = ibuf_contract(sync);
+		sum_sizes += size;
+	} while (size > 0 && sum_sizes < entry_size);
+}
+
+/*********************************************************************//**
+Determine if an insert buffer record has been encountered already.
+@return	TRUE if a new record, FALSE if possible duplicate */
+static
+ibool
+ibuf_get_volume_buffered_hash(
+/*==========================*/
+	const rec_t*	rec,	/*!< in: ibuf record in post-4.1 format */
+	const byte*	types,	/*!< in: fields */
+	const byte*	data,	/*!< in: start of user record data */
+	ulint		comp,	/*!< in: 0=ROW_FORMAT=REDUNDANT,
+				nonzero=ROW_FORMAT=COMPACT */
+	ulint*		hash,	/*!< in/out: hash array */
+	ulint		size)	/*!< in: number of elements in hash array */
+{
+	ulint		len;
+	ulint		fold;
+	ulint		bitmask;
+
+	len = ibuf_rec_get_size(
+		rec, types,
+		rec_get_n_fields_old(rec) - IBUF_REC_FIELD_USER, comp);
+	fold = ut_fold_binary(data, len);
+
+	hash += (fold / (CHAR_BIT * sizeof *hash)) % size;
+	bitmask = static_cast<ulint>(
+		1 << (fold % (CHAR_BIT * sizeof(*hash))));
+
+	if (*hash & bitmask) {
+
+		return(FALSE);
+	}
+
+	/* We have not seen this record yet.  Insert it. */
+	*hash |= bitmask;
+
+	return(TRUE);
+}
+
+#ifdef UNIV_DEBUG
+# define ibuf_get_volume_buffered_count(mtr,rec,hash,size,n_recs)	\
+	ibuf_get_volume_buffered_count_func(mtr,rec,hash,size,n_recs)
+#else /* UNIV_DEBUG */
+# define ibuf_get_volume_buffered_count(mtr,rec,hash,size,n_recs)	\
+	ibuf_get_volume_buffered_count_func(rec,hash,size,n_recs)
+#endif
+/*********************************************************************//**
+Update the estimate of the number of records on a page, and
+get the space taken by merging the buffered record to the index page.
+@return size of index record in bytes + an upper limit of the space
+taken in the page directory */
+static
+ulint
+ibuf_get_volume_buffered_count_func(
+/*================================*/
+#ifdef UNIV_DEBUG
+	mtr_t*		mtr,	/*!< in: mini-transaction owning rec */
+#endif /* UNIV_DEBUG */
+	const rec_t*	rec,	/*!< in: insert buffer record */
+	ulint*		hash,	/*!< in/out: hash array */
+	ulint		size,	/*!< in: number of elements in hash array */
+	lint*		n_recs)	/*!< in/out: estimated number of records
+				on the page that rec points to */
+{
+	ulint		len;
+	ibuf_op_t	ibuf_op;
+	const byte*	types;
+	ulint		n_fields;
+
+	ut_ad(mtr_memo_contains_page(mtr, rec, MTR_MEMO_PAGE_X_FIX)
+	      || mtr_memo_contains_page(mtr, rec, MTR_MEMO_PAGE_S_FIX));
+	ut_ad(ibuf_inside(mtr));
+
+	n_fields = rec_get_n_fields_old(rec);
+	ut_ad(n_fields > IBUF_REC_FIELD_USER);
+	n_fields -= IBUF_REC_FIELD_USER;
+
+	rec_get_nth_field_offs_old(rec, 1, &len);
+	/* This function is only invoked when buffering new
+	operations.  All pre-4.1 records should have been merged
+	when the database was started up. */
+	ut_a(len == 1);
+
+	if (rec_get_deleted_flag(rec, 0)) {
+		/* This record has been merged already,
+		but apparently the system crashed before
+		the change was discarded from the buffer.
+		Pretend that the record does not exist. */
+		return(0);
+	}
+
+	types = rec_get_nth_field_old(rec, IBUF_REC_FIELD_METADATA, &len);
+
+	switch (UNIV_EXPECT(len % DATA_NEW_ORDER_NULL_TYPE_BUF_SIZE,
+			    IBUF_REC_INFO_SIZE)) {
+	default:
+		ut_error;
+	case 0:
+		/* This ROW_TYPE=REDUNDANT record does not include an
+		operation counter.  Exclude it from the *n_recs,
+		because deletes cannot be buffered if there are
+		old-style inserts buffered for the page. */
+
+		len = ibuf_rec_get_size(rec, types, n_fields, 0);
+
+		return(len
+		       + rec_get_converted_extra_size(len, n_fields, 0)
+		       + page_dir_calc_reserved_space(1));
+	case 1:
+		/* This ROW_TYPE=COMPACT record does not include an
+		operation counter.  Exclude it from the *n_recs,
+		because deletes cannot be buffered if there are
+		old-style inserts buffered for the page. */
+		goto get_volume_comp;
+
+	case IBUF_REC_INFO_SIZE:
+		ibuf_op = (ibuf_op_t) types[IBUF_REC_OFFSET_TYPE];
+		break;
+	}
+
+	switch (ibuf_op) {
+	case IBUF_OP_INSERT:
+		/* Inserts can be done by updating a delete-marked record.
+		Because delete-mark and insert operations can be pointing to
+		the same records, we must not count duplicates. */
+	case IBUF_OP_DELETE_MARK:
+		/* There must be a record to delete-mark.
+		See if this record has been already buffered. */
+		if (n_recs && ibuf_get_volume_buffered_hash(
+			    rec, types + IBUF_REC_INFO_SIZE,
+			    types + len,
+			    types[IBUF_REC_OFFSET_FLAGS] & IBUF_REC_COMPACT,
+			    hash, size)) {
+			(*n_recs)++;
+		}
+
+		if (ibuf_op == IBUF_OP_DELETE_MARK) {
+			/* Setting the delete-mark flag does not
+			affect the available space on the page. */
+			return(0);
+		}
+		break;
+	case IBUF_OP_DELETE:
+		/* A record will be removed from the page. */
+		if (n_recs) {
+			(*n_recs)--;
+		}
+		/* While deleting a record actually frees up space,
+		we have to play it safe and pretend that it takes no
+		additional space (the record might not exist, etc.). */
+		return(0);
+	default:
+		ut_error;
+	}
+
+	ut_ad(ibuf_op == IBUF_OP_INSERT);
+
+get_volume_comp:
+	{
+		dtuple_t*	entry;
+		ulint		volume;
+		dict_index_t*	dummy_index;
+		mem_heap_t*	heap = mem_heap_create(500);
+
+		entry = ibuf_build_entry_from_ibuf_rec(
+			mtr, rec, heap, &dummy_index);
+
+		volume = rec_get_converted_size(dummy_index, entry, 0);
+
+		ibuf_dummy_index_free(dummy_index);
+		mem_heap_free(heap);
+
+		return(volume + page_dir_calc_reserved_space(1));
+	}
+}
+
+/*********************************************************************//**
+Gets an upper limit for the combined size of entries buffered in the insert
+buffer for a given page.
+@return upper limit for the volume of buffered inserts for the index
+page, in bytes; UNIV_PAGE_SIZE, if the entries for the index page span
+several pages in the insert buffer */
+static
+ulint
+ibuf_get_volume_buffered(
+/*=====================*/
+	const btr_pcur_t*pcur,	/*!< in: pcur positioned at a place in an
+				insert buffer tree where we would insert an
+				entry for the index page whose number is
+				page_no, latch mode has to be BTR_MODIFY_PREV
+				or BTR_MODIFY_TREE */
+	ulint		space,	/*!< in: space id */
+	ulint		page_no,/*!< in: page number of an index page */
+	lint*		n_recs,	/*!< in/out: minimum number of records on the
+				page after the buffered changes have been
+				applied, or NULL to disable the counting */
+	mtr_t*		mtr)	/*!< in: mini-transaction of pcur */
+{
+	ulint		volume;
+	const rec_t*	rec;
+	const page_t*	page;
+	ulint		prev_page_no;
+	const page_t*	prev_page;
+	ulint		next_page_no;
+	const page_t*	next_page;
+	/* bitmap of buffered recs */
+	ulint		hash_bitmap[128 / sizeof(ulint)];
+
+	ut_ad((pcur->latch_mode == BTR_MODIFY_PREV)
+	      || (pcur->latch_mode == BTR_MODIFY_TREE));
+
+	/* Count the volume of inserts earlier in the alphabetical order than
+	pcur */
+
+	volume = 0;
+
+	if (n_recs) {
+		memset(hash_bitmap, 0, sizeof hash_bitmap);
+	}
+
+	rec = btr_pcur_get_rec(pcur);
+	page = page_align(rec);
+	ut_ad(page_validate(page, ibuf->index));
+
+	if (page_rec_is_supremum(rec)) {
+		rec = page_rec_get_prev_const(rec);
+	}
+
+	for (; !page_rec_is_infimum(rec);
+	     rec = page_rec_get_prev_const(rec)) {
+		ut_ad(page_align(rec) == page);
+
+		if (page_no != ibuf_rec_get_page_no(mtr, rec)
+		    || space != ibuf_rec_get_space(mtr, rec)) {
+
+			goto count_later;
+		}
+
+		volume += ibuf_get_volume_buffered_count(
+			mtr, rec,
+			hash_bitmap, UT_ARR_SIZE(hash_bitmap), n_recs);
+	}
+
+	/* Look at the previous page */
+
+	prev_page_no = btr_page_get_prev(page, mtr);
+
+	if (prev_page_no == FIL_NULL) {
+
+		goto count_later;
+	}
+
+	{
+		buf_block_t*	block;
+
+		block = buf_page_get(
+			IBUF_SPACE_ID, 0, prev_page_no, RW_X_LATCH,
+			mtr);
+
+		buf_block_dbg_add_level(block, SYNC_IBUF_TREE_NODE);
+
+
+		prev_page = buf_block_get_frame(block);
+		ut_ad(page_validate(prev_page, ibuf->index));
+	}
+
+#ifdef UNIV_BTR_DEBUG
+	ut_a(btr_page_get_next(prev_page, mtr) == page_get_page_no(page));
+#endif /* UNIV_BTR_DEBUG */
+
+	rec = page_get_supremum_rec(prev_page);
+	rec = page_rec_get_prev_const(rec);
+
+	for (;; rec = page_rec_get_prev_const(rec)) {
+		ut_ad(page_align(rec) == prev_page);
+
+		if (page_rec_is_infimum(rec)) {
+
+			/* We cannot go to yet a previous page, because we
+			do not have the x-latch on it, and cannot acquire one
+			because of the latching order: we have to give up */
+
+			return(UNIV_PAGE_SIZE);
+		}
+
+		if (page_no != ibuf_rec_get_page_no(mtr, rec)
+		    || space != ibuf_rec_get_space(mtr, rec)) {
+
+			goto count_later;
+		}
+
+		volume += ibuf_get_volume_buffered_count(
+			mtr, rec,
+			hash_bitmap, UT_ARR_SIZE(hash_bitmap), n_recs);
+	}
+
+count_later:
+	rec = btr_pcur_get_rec(pcur);
+
+	if (!page_rec_is_supremum(rec)) {
+		rec = page_rec_get_next_const(rec);
+	}
+
+	for (; !page_rec_is_supremum(rec);
+	     rec = page_rec_get_next_const(rec)) {
+		if (page_no != ibuf_rec_get_page_no(mtr, rec)
+		    || space != ibuf_rec_get_space(mtr, rec)) {
+
+			return(volume);
+		}
+
+		volume += ibuf_get_volume_buffered_count(
+			mtr, rec,
+			hash_bitmap, UT_ARR_SIZE(hash_bitmap), n_recs);
+	}
+
+	/* Look at the next page */
+
+	next_page_no = btr_page_get_next(page, mtr);
+
+	if (next_page_no == FIL_NULL) {
+
+		return(volume);
+	}
+
+	{
+		buf_block_t*	block;
+
+		block = buf_page_get(
+			IBUF_SPACE_ID, 0, next_page_no, RW_X_LATCH,
+			mtr);
+
+		buf_block_dbg_add_level(block, SYNC_IBUF_TREE_NODE);
+
+
+		next_page = buf_block_get_frame(block);
+		ut_ad(page_validate(next_page, ibuf->index));
+	}
+
+#ifdef UNIV_BTR_DEBUG
+	ut_a(btr_page_get_prev(next_page, mtr) == page_get_page_no(page));
+#endif /* UNIV_BTR_DEBUG */
+
+	rec = page_get_infimum_rec(next_page);
+	rec = page_rec_get_next_const(rec);
+
+	for (;; rec = page_rec_get_next_const(rec)) {
+		ut_ad(page_align(rec) == next_page);
+
+		if (page_rec_is_supremum(rec)) {
+
+			/* We give up */
+
+			return(UNIV_PAGE_SIZE);
+		}
+
+		if (page_no != ibuf_rec_get_page_no(mtr, rec)
+		    || space != ibuf_rec_get_space(mtr, rec)) {
+
+			return(volume);
+		}
+
+		volume += ibuf_get_volume_buffered_count(
+			mtr, rec,
+			hash_bitmap, UT_ARR_SIZE(hash_bitmap), n_recs);
+	}
+}
+
+/*********************************************************************//**
+Reads the biggest tablespace id from the high end of the insert buffer
+tree and updates the counter in fil_system. */
+UNIV_INTERN
+void
+ibuf_update_max_tablespace_id(void)
+/*===============================*/
+{
+	ulint		max_space_id;
+	const rec_t*	rec;
+	const byte*	field;
+	ulint		len;
+	btr_pcur_t	pcur;
+	mtr_t		mtr;
+
+	ut_a(!dict_table_is_comp(ibuf->index->table));
+
+	ibuf_mtr_start(&mtr);
+
+	btr_pcur_open_at_index_side(
+		false, ibuf->index, BTR_SEARCH_LEAF, &pcur, true, 0, &mtr);
+
+	ut_ad(page_validate(btr_pcur_get_page(&pcur), ibuf->index));
+
+	btr_pcur_move_to_prev(&pcur, &mtr);
+
+	if (btr_pcur_is_before_first_on_page(&pcur)) {
+		/* The tree is empty */
+
+		max_space_id = 0;
+	} else {
+		rec = btr_pcur_get_rec(&pcur);
+
+		field = rec_get_nth_field_old(rec, IBUF_REC_FIELD_SPACE, &len);
+
+		ut_a(len == 4);
+
+		max_space_id = mach_read_from_4(field);
+	}
+
+	ibuf_mtr_commit(&mtr);
+
+	/* printf("Maximum space id in insert buffer %lu\n", max_space_id); */
+
+	fil_set_max_space_id_if_bigger(max_space_id);
+}
+
+#ifdef UNIV_DEBUG
+# define ibuf_get_entry_counter_low(mtr,rec,space,page_no)	\
+	ibuf_get_entry_counter_low_func(mtr,rec,space,page_no)
+#else /* UNIV_DEBUG */
+# define ibuf_get_entry_counter_low(mtr,rec,space,page_no)	\
+	ibuf_get_entry_counter_low_func(rec,space,page_no)
+#endif
+/****************************************************************//**
+Helper function for ibuf_get_entry_counter_func. Checks if rec is for
+(space, page_no), and if so, reads counter value from it and returns
+that + 1.
+@retval ULINT_UNDEFINED if the record does not contain any counter
+@retval 0 if the record is not for (space, page_no)
+@retval 1 + previous counter value, otherwise */
+static
+ulint
+ibuf_get_entry_counter_low_func(
+/*============================*/
+#ifdef UNIV_DEBUG
+	mtr_t*		mtr,		/*!< in: mini-transaction of rec */
+#endif /* UNIV_DEBUG */
+	const rec_t*	rec,		/*!< in: insert buffer record */
+	ulint		space,		/*!< in: space id */
+	ulint		page_no)	/*!< in: page number */
+{
+	ulint		counter;
+	const byte*	field;
+	ulint		len;
+
+	ut_ad(ibuf_inside(mtr));
+	ut_ad(mtr_memo_contains_page(mtr, rec, MTR_MEMO_PAGE_X_FIX)
+	      || mtr_memo_contains_page(mtr, rec, MTR_MEMO_PAGE_S_FIX));
+	ut_ad(rec_get_n_fields_old(rec) > 2);
+
+	field = rec_get_nth_field_old(rec, IBUF_REC_FIELD_MARKER, &len);
+
+	ut_a(len == 1);
+
+	/* Check the tablespace identifier. */
+	field = rec_get_nth_field_old(rec, IBUF_REC_FIELD_SPACE, &len);
+
+	ut_a(len == 4);
+
+	if (mach_read_from_4(field) != space) {
+
+		return(0);
+	}
+
+	/* Check the page offset. */
+	field = rec_get_nth_field_old(rec, IBUF_REC_FIELD_PAGE, &len);
+	ut_a(len == 4);
+
+	if (mach_read_from_4(field) != page_no) {
+
+		return(0);
+	}
+
+	/* Check if the record contains a counter field. */
+	field = rec_get_nth_field_old(rec, IBUF_REC_FIELD_METADATA, &len);
+
+	switch (len % DATA_NEW_ORDER_NULL_TYPE_BUF_SIZE) {
+	default:
+		ut_error;
+	case 0: /* ROW_FORMAT=REDUNDANT */
+	case 1: /* ROW_FORMAT=COMPACT */
+		return(ULINT_UNDEFINED);
+
+	case IBUF_REC_INFO_SIZE:
+		counter = mach_read_from_2(field + IBUF_REC_OFFSET_COUNTER);
+		ut_a(counter < 0xFFFF);
+		return(counter + 1);
+	}
+}
+
+#ifdef UNIV_DEBUG
+# define ibuf_get_entry_counter(space,page_no,rec,mtr,exact_leaf) \
+	ibuf_get_entry_counter_func(space,page_no,rec,mtr,exact_leaf)
+#else /* UNIV_DEBUG */
+# define ibuf_get_entry_counter(space,page_no,rec,mtr,exact_leaf) \
+	ibuf_get_entry_counter_func(space,page_no,rec,exact_leaf)
+#endif
+
+/****************************************************************//**
+Calculate the counter field for an entry based on the current
+last record in ibuf for (space, page_no).
+@return	the counter field, or ULINT_UNDEFINED
+if we should abort this insertion to ibuf */
+static
+ulint
+ibuf_get_entry_counter_func(
+/*========================*/
+	ulint		space,		/*!< in: space id of entry */
+	ulint		page_no,	/*!< in: page number of entry */
+	const rec_t*	rec,		/*!< in: the record preceding the
+					insertion point */
+#ifdef UNIV_DEBUG
+	mtr_t*		mtr,		/*!< in: mini-transaction */
+#endif /* UNIV_DEBUG */
+	ibool		only_leaf)	/*!< in: TRUE if this is the only
+					leaf page that can contain entries
+					for (space,page_no), that is, there
+					was no exact match for (space,page_no)
+					in the node pointer */
+{
+	ut_ad(ibuf_inside(mtr));
+	ut_ad(mtr_memo_contains_page(mtr, rec, MTR_MEMO_PAGE_X_FIX));
+	ut_ad(page_validate(page_align(rec), ibuf->index));
+
+	if (page_rec_is_supremum(rec)) {
+		/* This is just for safety. The record should be a
+		page infimum or a user record. */
+		ut_ad(0);
+		return(ULINT_UNDEFINED);
+	} else if (!page_rec_is_infimum(rec)) {
+		return(ibuf_get_entry_counter_low(mtr, rec, space, page_no));
+	} else if (only_leaf
+		   || fil_page_get_prev(page_align(rec)) == FIL_NULL) {
+		/* The parent node pointer did not contain the
+		searched for (space, page_no), which means that the
+		search ended on the correct page regardless of the
+		counter value, and since we're at the infimum record,
+		there are no existing records. */
+		return(0);
+	} else {
+		/* We used to read the previous page here. It would
+		break the latching order, because the caller has
+		buffer-fixed an insert buffer bitmap page. */
+		return(ULINT_UNDEFINED);
+	}
+}
+
+/*********************************************************************//**
+Buffer an operation in the insert/delete buffer, instead of doing it
+directly to the disk page, if this is possible.
+@return	DB_SUCCESS, DB_STRONG_FAIL or other error */
+static __attribute__((nonnull, warn_unused_result))
+dberr_t
+ibuf_insert_low(
+/*============*/
+	ulint		mode,	/*!< in: BTR_MODIFY_PREV or BTR_MODIFY_TREE */
+	ibuf_op_t	op,	/*!< in: operation type */
+	ibool		no_counter,
+				/*!< in: TRUE=use 5.0.3 format;
+				FALSE=allow delete buffering */
+	const dtuple_t*	entry,	/*!< in: index entry to insert */
+	ulint		entry_size,
+				/*!< in: rec_get_converted_size(index, entry) */
+	dict_index_t*	index,	/*!< in: index where to insert; must not be
+				unique or clustered */
+	ulint		space,	/*!< in: space id where to insert */
+	ulint		zip_size,/*!< in: compressed page size in bytes, or 0 */
+	ulint		page_no,/*!< in: page number where to insert */
+	que_thr_t*	thr)	/*!< in: query thread */
+{
+	big_rec_t*	dummy_big_rec;
+	btr_pcur_t	pcur;
+	btr_cur_t*	cursor;
+	dtuple_t*	ibuf_entry;
+	mem_heap_t*	offsets_heap	= NULL;
+	mem_heap_t*	heap;
+	ulint*		offsets		= NULL;
+	ulint		buffered;
+	lint		min_n_recs;
+	rec_t*		ins_rec;
+	ibool		old_bit_value;
+	page_t*		bitmap_page;
+	buf_block_t*	block;
+	page_t*		root;
+	dberr_t		err;
+	ibool		do_merge;
+	ulint		space_ids[IBUF_MAX_N_PAGES_MERGED];
+	ib_int64_t	space_versions[IBUF_MAX_N_PAGES_MERGED];
+	ulint		page_nos[IBUF_MAX_N_PAGES_MERGED];
+	ulint		n_stored;
+	mtr_t		mtr;
+	mtr_t		bitmap_mtr;
+
+	ut_a(!dict_index_is_clust(index));
+	ut_ad(dtuple_check_typed(entry));
+	ut_ad(ut_is_2pow(zip_size));
+	ut_ad(!no_counter || op == IBUF_OP_INSERT);
+	ut_a(op < IBUF_OP_COUNT);
+
+	do_merge = FALSE;
+
+	/* Perform dirty reads of ibuf->size and ibuf->max_size, to
+	reduce ibuf_mutex contention. Given that ibuf->max_size and
+	ibuf->size fit in a machine word, this should be OK; at worst
+	we are doing some excessive ibuf_contract() or occasionally
+	skipping an ibuf_contract(). */
+	if (ibuf->max_size == 0) {
+		return(DB_STRONG_FAIL);
+	}
+
+	if (ibuf->size >= ibuf->max_size + IBUF_CONTRACT_DO_NOT_INSERT) {
+		/* Insert buffer is now too big, contract it but do not try
+		to insert */
+
+
+#ifdef UNIV_IBUF_DEBUG
+		fputs("Ibuf too big\n", stderr);
+#endif
+		/* Use synchronous contract (== TRUE) */
+		ibuf_contract(TRUE);
+
+		return(DB_STRONG_FAIL);
+	}
+
+	heap = mem_heap_create(1024);
+
+	/* Build the entry which contains the space id and the page number
+	as the first fields and the type information for other fields, and
+	which will be inserted to the insert buffer. Using a counter value
+	of 0xFFFF we find the last record for (space, page_no), from which
+	we can then read the counter value N and use N + 1 in the record we
+	insert. (We patch the ibuf_entry's counter field to the correct
+	value just before actually inserting the entry.) */
+
+	ibuf_entry = ibuf_entry_build(
+		op, index, entry, space, page_no,
+		no_counter ? ULINT_UNDEFINED : 0xFFFF, heap);
+
+	/* Open a cursor to the insert buffer tree to calculate if we can add
+	the new entry to it without exceeding the free space limit for the
+	page. */
+
+	if (mode == BTR_MODIFY_TREE) {
+		for (;;) {
+			mutex_enter(&ibuf_pessimistic_insert_mutex);
+			mutex_enter(&ibuf_mutex);
+
+			if (UNIV_LIKELY(ibuf_data_enough_free_for_insert())) {
+
+				break;
+			}
+
+			mutex_exit(&ibuf_mutex);
+			mutex_exit(&ibuf_pessimistic_insert_mutex);
+
+			if (UNIV_UNLIKELY(!ibuf_add_free_page())) {
+
+				mem_heap_free(heap);
+				return(DB_STRONG_FAIL);
+			}
+		}
+	}
+
+	ibuf_mtr_start(&mtr);
+
+	btr_pcur_open(ibuf->index, ibuf_entry, PAGE_CUR_LE, mode, &pcur, &mtr);
+	ut_ad(page_validate(btr_pcur_get_page(&pcur), ibuf->index));
+
+	/* Find out the volume of already buffered inserts for the same index
+	page */
+	min_n_recs = 0;
+	buffered = ibuf_get_volume_buffered(&pcur, space, page_no,
+					    op == IBUF_OP_DELETE
+					    ? &min_n_recs
+					    : NULL, &mtr);
+
+	if (op == IBUF_OP_DELETE
+	    && (min_n_recs < 2
+		|| buf_pool_watch_occurred(space, page_no))) {
+		/* The page could become empty after the record is
+		deleted, or the page has been read in to the buffer
+		pool.  Refuse to buffer the operation. */
+
+		/* The buffer pool watch is needed for IBUF_OP_DELETE
+		because of latching order considerations.  We can
+		check buf_pool_watch_occurred() only after latching
+		the insert buffer B-tree pages that contain buffered
+		changes for the page.  We never buffer IBUF_OP_DELETE,
+		unless some IBUF_OP_INSERT or IBUF_OP_DELETE_MARK have
+		been previously buffered for the page.  Because there
+		are buffered operations for the page, the insert
+		buffer B-tree page latches held by mtr will guarantee
+		that no changes for the user page will be merged
+		before mtr_commit(&mtr).  We must not mtr_commit(&mtr)
+		until after the IBUF_OP_DELETE has been buffered. */
+
+fail_exit:
+		if (mode == BTR_MODIFY_TREE) {
+			mutex_exit(&ibuf_mutex);
+			mutex_exit(&ibuf_pessimistic_insert_mutex);
+		}
+
+		err = DB_STRONG_FAIL;
+		goto func_exit;
+	}
+
+	/* After this point, the page could still be loaded to the
+	buffer pool, but we do not have to care about it, since we are
+	holding a latch on the insert buffer leaf page that contains
+	buffered changes for (space, page_no).  If the page enters the
+	buffer pool, buf_page_io_complete() for (space, page_no) will
+	have to acquire a latch on the same insert buffer leaf page,
+	which it cannot do until we have buffered the IBUF_OP_DELETE
+	and done mtr_commit(&mtr) to release the latch. */
+
+#ifdef UNIV_IBUF_COUNT_DEBUG
+	ut_a((buffered == 0) || ibuf_count_get(space, page_no));
+#endif
+	ibuf_mtr_start(&bitmap_mtr);
+
+	bitmap_page = ibuf_bitmap_get_map_page(space, page_no,
+					       zip_size, &bitmap_mtr);
+
+	/* We check if the index page is suitable for buffered entries */
+
+	if (buf_page_peek(space, page_no)
+	    || lock_rec_expl_exist_on_page(space, page_no)) {
+
+		ibuf_mtr_commit(&bitmap_mtr);
+		goto fail_exit;
+	}
+
+	if (op == IBUF_OP_INSERT) {
+		ulint	bits = ibuf_bitmap_page_get_bits(
+			bitmap_page, page_no, zip_size, IBUF_BITMAP_FREE,
+			&bitmap_mtr);
+
+		if (buffered + entry_size + page_dir_calc_reserved_space(1)
+		    > ibuf_index_page_calc_free_from_bits(zip_size, bits)) {
+			/* Release the bitmap page latch early. */
+			ibuf_mtr_commit(&bitmap_mtr);
+
+			/* It may not fit */
+			do_merge = TRUE;
+
+			ibuf_get_merge_page_nos(FALSE,
+						btr_pcur_get_rec(&pcur), &mtr,
+						space_ids, space_versions,
+						page_nos, &n_stored);
+
+			goto fail_exit;
+		}
+	}
+
+	if (!no_counter) {
+		/* Patch correct counter value to the entry to
+		insert. This can change the insert position, which can
+		result in the need to abort in some cases. */
+		ulint		counter = ibuf_get_entry_counter(
+			space, page_no, btr_pcur_get_rec(&pcur), &mtr,
+			btr_pcur_get_btr_cur(&pcur)->low_match
+			< IBUF_REC_FIELD_METADATA);
+		dfield_t*	field;
+
+		if (counter == ULINT_UNDEFINED) {
+			ibuf_mtr_commit(&bitmap_mtr);
+			goto fail_exit;
+		}
+
+		field = dtuple_get_nth_field(
+			ibuf_entry, IBUF_REC_FIELD_METADATA);
+		mach_write_to_2(
+			(byte*) dfield_get_data(field)
+			+ IBUF_REC_OFFSET_COUNTER, counter);
+	}
+
+	/* Set the bitmap bit denoting that the insert buffer contains
+	buffered entries for this index page, if the bit is not set yet */
+
+	old_bit_value = ibuf_bitmap_page_get_bits(
+		bitmap_page, page_no, zip_size,
+		IBUF_BITMAP_BUFFERED, &bitmap_mtr);
+
+	if (!old_bit_value) {
+		ibuf_bitmap_page_set_bits(bitmap_page, page_no, zip_size,
+					  IBUF_BITMAP_BUFFERED, TRUE,
+					  &bitmap_mtr);
+	}
+
+	ibuf_mtr_commit(&bitmap_mtr);
+
+	cursor = btr_pcur_get_btr_cur(&pcur);
+
+	if (mode == BTR_MODIFY_PREV) {
+		err = btr_cur_optimistic_insert(
+			BTR_NO_LOCKING_FLAG,
+			cursor, &offsets, &offsets_heap,
+			ibuf_entry, &ins_rec,
+			&dummy_big_rec, 0, thr, &mtr);
+		block = btr_cur_get_block(cursor);
+		ut_ad(buf_block_get_space(block) == IBUF_SPACE_ID);
+
+		/* If this is the root page, update ibuf->empty. */
+		if (UNIV_UNLIKELY(buf_block_get_page_no(block)
+				  == FSP_IBUF_TREE_ROOT_PAGE_NO)) {
+			const page_t*	root = buf_block_get_frame(block);
+
+			ut_ad(page_get_space_id(root) == IBUF_SPACE_ID);
+			ut_ad(page_get_page_no(root)
+			      == FSP_IBUF_TREE_ROOT_PAGE_NO);
+
+			ibuf->empty = page_is_empty(root);
+		}
+	} else {
+		ut_ad(mode == BTR_MODIFY_TREE);
+
+		/* We acquire an x-latch to the root page before the insert,
+		because a pessimistic insert releases the tree x-latch,
+		which would cause the x-latching of the root after that to
+		break the latching order. */
+
+		root = ibuf_tree_root_get(&mtr);
+
+		err = btr_cur_optimistic_insert(
+			BTR_NO_LOCKING_FLAG | BTR_NO_UNDO_LOG_FLAG,
+			cursor, &offsets, &offsets_heap,
+			ibuf_entry, &ins_rec,
+			&dummy_big_rec, 0, thr, &mtr);
+
+		if (err == DB_FAIL) {
+			err = btr_cur_pessimistic_insert(
+				BTR_NO_LOCKING_FLAG | BTR_NO_UNDO_LOG_FLAG,
+				cursor, &offsets, &offsets_heap,
+				ibuf_entry, &ins_rec,
+				&dummy_big_rec, 0, thr, &mtr);
+		}
+
+		mutex_exit(&ibuf_pessimistic_insert_mutex);
+		ibuf_size_update(root, &mtr);
+		mutex_exit(&ibuf_mutex);
+		ibuf->empty = page_is_empty(root);
+
+		block = btr_cur_get_block(cursor);
+		ut_ad(buf_block_get_space(block) == IBUF_SPACE_ID);
+	}
+
+	if (offsets_heap) {
+		mem_heap_free(offsets_heap);
+	}
+
+	if (err == DB_SUCCESS && op != IBUF_OP_DELETE) {
+		/* Update the page max trx id field */
+		page_update_max_trx_id(block, NULL,
+				       thr_get_trx(thr)->id, &mtr);
+	}
+
+func_exit:
+#ifdef UNIV_IBUF_COUNT_DEBUG
+	if (err == DB_SUCCESS) {
+		fprintf(stderr,
+			"Incrementing ibuf count of space %lu page %lu\n"
+			"from %lu by 1\n", space, page_no,
+			ibuf_count_get(space, page_no));
+
+		ibuf_count_set(space, page_no,
+			       ibuf_count_get(space, page_no) + 1);
+	}
+#endif
+
+	ibuf_mtr_commit(&mtr);
+	btr_pcur_close(&pcur);
+
+	mem_heap_free(heap);
+
+	if (err == DB_SUCCESS && mode == BTR_MODIFY_TREE) {
+		ibuf_contract_after_insert(entry_size);
+	}
+
+	if (do_merge) {
+#ifdef UNIV_IBUF_DEBUG
+		ut_a(n_stored <= IBUF_MAX_N_PAGES_MERGED);
+#endif
+		buf_read_ibuf_merge_pages(false, space_ids, space_versions,
+					  page_nos, n_stored);
+	}
+
+	return(err);
+}
+
+/*********************************************************************//**
+Buffer an operation in the insert/delete buffer, instead of doing it
+directly to the disk page, if this is possible. Does not do it if the index
+is clustered or unique.
+@return	TRUE if success */
+UNIV_INTERN
+ibool
+ibuf_insert(
+/*========*/
+	ibuf_op_t	op,	/*!< in: operation type */
+	const dtuple_t*	entry,	/*!< in: index entry to insert */
+	dict_index_t*	index,	/*!< in: index where to insert */
+	ulint		space,	/*!< in: space id where to insert */
+	ulint		zip_size,/*!< in: compressed page size in bytes, or 0 */
+	ulint		page_no,/*!< in: page number where to insert */
+	que_thr_t*	thr)	/*!< in: query thread */
+{
+	dberr_t		err;
+	ulint		entry_size;
+	ibool		no_counter;
+	/* Read the settable global variable ibuf_use only once in
+	this function, so that we will have a consistent view of it. */
+	ibuf_use_t	use		= ibuf_use;
+	DBUG_ENTER("ibuf_insert");
+
+	DBUG_PRINT("ibuf", ("op: %d, space: %ld, page_no: %ld",
+			    op, space, page_no));
+
+	ut_ad(dtuple_check_typed(entry));
+	ut_ad(ut_is_2pow(zip_size));
+
+	ut_a(!dict_index_is_clust(index));
+
+	no_counter = use <= IBUF_USE_INSERT;
+
+	switch (op) {
+	case IBUF_OP_INSERT:
+		switch (use) {
+		case IBUF_USE_NONE:
+		case IBUF_USE_DELETE:
+		case IBUF_USE_DELETE_MARK:
+			DBUG_RETURN(FALSE);
+		case IBUF_USE_INSERT:
+		case IBUF_USE_INSERT_DELETE_MARK:
+		case IBUF_USE_ALL:
+			goto check_watch;
+		case IBUF_USE_COUNT:
+			break;
+		}
+		break;
+	case IBUF_OP_DELETE_MARK:
+		switch (use) {
+		case IBUF_USE_NONE:
+		case IBUF_USE_INSERT:
+			DBUG_RETURN(FALSE);
+		case IBUF_USE_DELETE_MARK:
+		case IBUF_USE_DELETE:
+		case IBUF_USE_INSERT_DELETE_MARK:
+		case IBUF_USE_ALL:
+			ut_ad(!no_counter);
+			goto check_watch;
+		case IBUF_USE_COUNT:
+			break;
+		}
+		break;
+	case IBUF_OP_DELETE:
+		switch (use) {
+		case IBUF_USE_NONE:
+		case IBUF_USE_INSERT:
+		case IBUF_USE_INSERT_DELETE_MARK:
+			DBUG_RETURN(FALSE);
+		case IBUF_USE_DELETE_MARK:
+		case IBUF_USE_DELETE:
+		case IBUF_USE_ALL:
+			ut_ad(!no_counter);
+			goto skip_watch;
+		case IBUF_USE_COUNT:
+			break;
+		}
+		break;
+	case IBUF_OP_COUNT:
+		break;
+	}
+
+	/* unknown op or use */
+	ut_error;
+
+check_watch:
+	/* If a thread attempts to buffer an insert on a page while a
+	purge is in progress on the same page, the purge must not be
+	buffered, because it could remove a record that was
+	re-inserted later.  For simplicity, we block the buffering of
+	all operations on a page that has a purge pending.
+
+	We do not check this in the IBUF_OP_DELETE case, because that
+	would always trigger the buffer pool watch during purge and
+	thus prevent the buffering of delete operations.  We assume
+	that the issuer of IBUF_OP_DELETE has called
+	buf_pool_watch_set(space, page_no). */
+
+	{
+		buf_page_t*	bpage;
+		buf_pool_t*	buf_pool = buf_pool_get(space, page_no);
+		bpage = buf_page_get_also_watch(buf_pool, space, page_no);
+
+		if (UNIV_LIKELY_NULL(bpage)) {
+			/* A buffer pool watch has been set or the
+			page has been read into the buffer pool.
+			Do not buffer the request.  If a purge operation
+			is being buffered, have this request executed
+			directly on the page in the buffer pool after the
+			buffered entries for this page have been merged. */
+			DBUG_RETURN(FALSE);
+		}
+	}
+
+skip_watch:
+	entry_size = rec_get_converted_size(index, entry, 0);
+
+	if (entry_size
+	    >= page_get_free_space_of_empty(dict_table_is_comp(index->table))
+	    / 2) {
+
+		DBUG_RETURN(FALSE);
+	}
+
+	err = ibuf_insert_low(BTR_MODIFY_PREV, op, no_counter,
+			      entry, entry_size,
+			      index, space, zip_size, page_no, thr);
+	if (err == DB_FAIL) {
+		err = ibuf_insert_low(BTR_MODIFY_TREE, op, no_counter,
+				      entry, entry_size,
+				      index, space, zip_size, page_no, thr);
+	}
+
+	if (err == DB_SUCCESS) {
+#ifdef UNIV_IBUF_DEBUG
+		/* fprintf(stderr, "Ibuf insert for page no %lu of index %s\n",
+		page_no, index->name); */
+#endif
+		DBUG_RETURN(TRUE);
+
+	} else {
+		ut_a(err == DB_STRONG_FAIL || err == DB_TOO_BIG_RECORD);
+
+		DBUG_RETURN(FALSE);
+	}
+}
+
+/********************************************************************//**
+During merge, inserts to an index page a secondary index entry extracted
+from the insert buffer.
+@return	newly inserted record */
+static __attribute__((nonnull))
+rec_t*
+ibuf_insert_to_index_page_low(
+/*==========================*/
+	const dtuple_t*	entry,	/*!< in: buffered entry to insert */
+	buf_block_t*	block,	/*!< in/out: index page where the buffered
+				entry should be placed */
+	dict_index_t*	index,	/*!< in: record descriptor */
+	ulint**		offsets,/*!< out: offsets on *rec */
+	mem_heap_t*	heap,	/*!< in/out: memory heap */
+	mtr_t*		mtr,	/*!< in/out: mtr */
+	page_cur_t*	page_cur)/*!< in/out: cursor positioned on the record
+				after which to insert the buffered entry */
+{
+	const page_t*	page;
+	ulint		space;
+	ulint		page_no;
+	ulint		zip_size;
+	const page_t*	bitmap_page;
+	ulint		old_bits;
+	rec_t*		rec;
+	DBUG_ENTER("ibuf_insert_to_index_page_low");
+
+	rec = page_cur_tuple_insert(page_cur, entry, index,
+				    offsets, &heap, 0, mtr);
+	if (rec != NULL) {
+		DBUG_RETURN(rec);
+	}
+
+	/* Page reorganization or recompression should already have
+	been attempted by page_cur_tuple_insert(). Besides, per
+	ibuf_index_page_calc_free_zip() the page should not have been
+	recompressed or reorganized. */
+	ut_ad(!buf_block_get_page_zip(block));
+
+	/* If the record did not fit, reorganize */
+
+	btr_page_reorganize(page_cur, index, mtr);
+
+	/* This time the record must fit */
+
+	rec = page_cur_tuple_insert(page_cur, entry, index,
+				    offsets, &heap, 0, mtr);
+	if (rec != NULL) {
+		DBUG_RETURN(rec);
+	}
+
+	page = buf_block_get_frame(block);
+
+	ut_print_timestamp(stderr);
+
+	fprintf(stderr,
+		"  InnoDB: Error: Insert buffer insert fails;"
+		" page free %lu, dtuple size %lu\n",
+		(ulong) page_get_max_insert_size(page, 1),
+		(ulong) rec_get_converted_size(index, entry, 0));
+	fputs("InnoDB: Cannot insert index record ", stderr);
+	dtuple_print(stderr, entry);
+	fputs("\nInnoDB: The table where this index record belongs\n"
+	      "InnoDB: is now probably corrupt. Please run CHECK TABLE on\n"
+	      "InnoDB: that table.\n", stderr);
+
+	space = page_get_space_id(page);
+	zip_size = buf_block_get_zip_size(block);
+	page_no = page_get_page_no(page);
+
+	bitmap_page = ibuf_bitmap_get_map_page(space, page_no, zip_size, mtr);
+	old_bits = ibuf_bitmap_page_get_bits(bitmap_page, page_no, zip_size,
+					     IBUF_BITMAP_FREE, mtr);
+
+	fprintf(stderr,
+		"InnoDB: space %lu, page %lu, zip_size %lu, bitmap bits %lu\n",
+		(ulong) space, (ulong) page_no,
+		(ulong) zip_size, (ulong) old_bits);
+
+	fputs("InnoDB: Submit a detailed bug report"
+	      " to http://bugs.mysql.com\n", stderr);
+	ut_ad(0);
+	DBUG_RETURN(NULL);
+}
+
+/************************************************************************
+During merge, inserts to an index page a secondary index entry extracted
+from the insert buffer. */
+static
+void
+ibuf_insert_to_index_page(
+/*======================*/
+	const dtuple_t*	entry,	/*!< in: buffered entry to insert */
+	buf_block_t*	block,	/*!< in/out: index page where the buffered entry
+				should be placed */
+	dict_index_t*	index,	/*!< in: record descriptor */
+	mtr_t*		mtr)	/*!< in: mtr */
+{
+	page_cur_t	page_cur;
+	ulint		low_match;
+	page_t*		page		= buf_block_get_frame(block);
+	rec_t*		rec;
+	ulint*		offsets;
+	mem_heap_t*	heap;
+
+	DBUG_ENTER("ibuf_insert_to_index_page");
+
+	DBUG_PRINT("ibuf", ("page_no: %ld", buf_block_get_page_no(block)));
+	DBUG_PRINT("ibuf", ("index name: %s", index->name));
+	DBUG_PRINT("ibuf", ("online status: %d",
+			    dict_index_get_online_status(index)));
+
+	ut_ad(ibuf_inside(mtr));
+	ut_ad(dtuple_check_typed(entry));
+	ut_ad(!buf_block_align(page)->index);
+
+	if (UNIV_UNLIKELY(dict_table_is_comp(index->table)
+			  != (ibool)!!page_is_comp(page))) {
+		fputs("InnoDB: Trying to insert a record from"
+		      " the insert buffer to an index page\n"
+		      "InnoDB: but the 'compact' flag does not match!\n",
+		      stderr);
+		goto dump;
+	}
+
+	rec = page_rec_get_next(page_get_infimum_rec(page));
+
+	if (page_rec_is_supremum(rec)) {
+		fputs("InnoDB: Trying to insert a record from"
+		      " the insert buffer to an index page\n"
+		      "InnoDB: but the index page is empty!\n",
+		      stderr);
+		goto dump;
+	}
+
+	if (UNIV_UNLIKELY(rec_get_n_fields(rec, index)
+			  != dtuple_get_n_fields(entry))) {
+		fputs("InnoDB: Trying to insert a record from"
+		      " the insert buffer to an index page\n"
+		      "InnoDB: but the number of fields does not match!\n",
+		      stderr);
+dump:
+		buf_page_print(page, 0, BUF_PAGE_PRINT_NO_CRASH);
+
+		dtuple_print(stderr, entry);
+		ut_ad(0);
+
+		fputs("InnoDB: The table where where"
+		      " this index record belongs\n"
+		      "InnoDB: is now probably corrupt."
+		      " Please run CHECK TABLE on\n"
+		      "InnoDB: your tables.\n"
+		      "InnoDB: Submit a detailed bug report to"
+		      " http://bugs.mysql.com!\n", stderr);
+
+		DBUG_VOID_RETURN;
+	}
+
+	low_match = page_cur_search(block, index, entry,
+				    PAGE_CUR_LE, &page_cur);
+
+	heap = mem_heap_create(
+		sizeof(upd_t)
+		+ REC_OFFS_HEADER_SIZE * sizeof(*offsets)
+		+ dtuple_get_n_fields(entry)
+		* (sizeof(upd_field_t) + sizeof *offsets));
+
+	if (UNIV_UNLIKELY(low_match == dtuple_get_n_fields(entry))) {
+		upd_t*		update;
+		page_zip_des_t*	page_zip;
+
+		rec = page_cur_get_rec(&page_cur);
+
+		/* This is based on
+		row_ins_sec_index_entry_by_modify(BTR_MODIFY_LEAF). */
+		ut_ad(rec_get_deleted_flag(rec, page_is_comp(page)));
+
+		offsets = rec_get_offsets(rec, index, NULL, ULINT_UNDEFINED,
+					  &heap);
+		update = row_upd_build_sec_rec_difference_binary(
+			rec, index, offsets, entry, heap);
+
+		page_zip = buf_block_get_page_zip(block);
+
+		if (update->n_fields == 0) {
+			/* The records only differ in the delete-mark.
+			Clear the delete-mark, like we did before
+			Bug #56680 was fixed. */
+			btr_cur_set_deleted_flag_for_ibuf(
+				rec, page_zip, FALSE, mtr);
+			goto updated_in_place;
+		}
+
+		/* Copy the info bits. Clear the delete-mark. */
+		update->info_bits = rec_get_info_bits(rec, page_is_comp(page));
+		update->info_bits &= ~REC_INFO_DELETED_FLAG;
+
+		/* We cannot invoke btr_cur_optimistic_update() here,
+		because we do not have a btr_cur_t or que_thr_t,
+		as the insert buffer merge occurs at a very low level. */
+		if (!row_upd_changes_field_size_or_external(index, offsets,
+							    update)
+		    && (!page_zip || btr_cur_update_alloc_zip(
+				page_zip, &page_cur, index, offsets,
+				rec_offs_size(offsets), false, mtr))) {
+			/* This is the easy case. Do something similar
+			to btr_cur_update_in_place(). */
+			rec = page_cur_get_rec(&page_cur);
+			row_upd_rec_in_place(rec, index, offsets,
+					     update, page_zip);
+
+			/* Log the update in place operation. During recovery
+			MLOG_COMP_REC_UPDATE_IN_PLACE/MLOG_REC_UPDATE_IN_PLACE
+			expects trx_id, roll_ptr for secondary indexes. So we
+			just write dummy trx_id(0), roll_ptr(0) */
+			btr_cur_update_in_place_log(BTR_KEEP_SYS_FLAG, rec,
+						    index, update, 0, 0, mtr);
+			DBUG_EXECUTE_IF(
+				"crash_after_log_ibuf_upd_inplace",
+				log_buffer_flush_to_disk();
+				ib_logf(IB_LOG_LEVEL_INFO,
+					"Wrote log record for ibuf update in "
+					"place operation");
+				DBUG_SUICIDE();
+			);
+
+			goto updated_in_place;
+		}
+
+		/* btr_cur_update_alloc_zip() may have changed this */
+		rec = page_cur_get_rec(&page_cur);
+
+		/* A collation may identify values that differ in
+		storage length.
+		Some examples (1 or 2 bytes):
+		utf8_turkish_ci: I = U+0131 LATIN SMALL LETTER DOTLESS I
+		utf8_general_ci: S = U+00DF LATIN SMALL LETTER SHARP S
+		utf8_general_ci: A = U+00E4 LATIN SMALL LETTER A WITH DIAERESIS
+
+		latin1_german2_ci: SS = U+00DF LATIN SMALL LETTER SHARP S
+
+		Examples of a character (3-byte UTF-8 sequence)
+		identified with 2 or 4 characters (1-byte UTF-8 sequences):
+
+		utf8_unicode_ci: 'II' = U+2171 SMALL ROMAN NUMERAL TWO
+		utf8_unicode_ci: '(10)' = U+247D PARENTHESIZED NUMBER TEN
+		*/
+
+		/* Delete the different-length record, and insert the
+		buffered one. */
+
+		lock_rec_store_on_page_infimum(block, rec);
+		page_cur_delete_rec(&page_cur, index, offsets, mtr);
+		page_cur_move_to_prev(&page_cur);
+		rec = ibuf_insert_to_index_page_low(entry, block, index,
+				      		    &offsets, heap, mtr,
+						    &page_cur);
+
+		ut_ad(!cmp_dtuple_rec(entry, rec, offsets));
+		lock_rec_restore_from_page_infimum(block, rec, block);
+	} else {
+		offsets = NULL;
+		ibuf_insert_to_index_page_low(entry, block, index,
+					      &offsets, heap, mtr,
+					      &page_cur);
+	}
+updated_in_place:
+	mem_heap_free(heap);
+
+	DBUG_VOID_RETURN;
+}
+
+/****************************************************************//**
+During merge, sets the delete mark on a record for a secondary index
+entry. */
+static
+void
+ibuf_set_del_mark(
+/*==============*/
+	const dtuple_t*		entry,	/*!< in: entry */
+	buf_block_t*		block,	/*!< in/out: block */
+	const dict_index_t*	index,	/*!< in: record descriptor */
+	mtr_t*			mtr)	/*!< in: mtr */
+{
+	page_cur_t	page_cur;
+	ulint		low_match;
+
+	ut_ad(ibuf_inside(mtr));
+	ut_ad(dtuple_check_typed(entry));
+
+	low_match = page_cur_search(
+		block, index, entry, PAGE_CUR_LE, &page_cur);
+
+	if (low_match == dtuple_get_n_fields(entry)) {
+		rec_t*		rec;
+		page_zip_des_t*	page_zip;
+
+		rec = page_cur_get_rec(&page_cur);
+		page_zip = page_cur_get_page_zip(&page_cur);
+
+		/* Delete mark the old index record. According to a
+		comment in row_upd_sec_index_entry(), it can already
+		have been delete marked if a lock wait occurred in
+		row_ins_sec_index_entry() in a previous invocation of
+		row_upd_sec_index_entry(). */
+
+		if (UNIV_LIKELY
+		    (!rec_get_deleted_flag(
+			    rec, dict_table_is_comp(index->table)))) {
+			btr_cur_set_deleted_flag_for_ibuf(rec, page_zip,
+							  TRUE, mtr);
+		}
+	} else {
+		const page_t*		page
+			= page_cur_get_page(&page_cur);
+		const buf_block_t*	block
+			= page_cur_get_block(&page_cur);
+
+		ut_print_timestamp(stderr);
+		fputs("  InnoDB: unable to find a record to delete-mark\n",
+		      stderr);
+		fputs("InnoDB: tuple ", stderr);
+		dtuple_print(stderr, entry);
+		fputs("\n"
+		      "InnoDB: record ", stderr);
+		rec_print(stderr, page_cur_get_rec(&page_cur), index);
+		fprintf(stderr, "\nspace %u offset %u"
+			" (%u records, index id %llu)\n"
+			"InnoDB: Submit a detailed bug report"
+			" to http://bugs.mysql.com\n",
+			(unsigned) buf_block_get_space(block),
+			(unsigned) buf_block_get_page_no(block),
+			(unsigned) page_get_n_recs(page),
+			(ulonglong) btr_page_get_index_id(page));
+		ut_ad(0);
+	}
+}
+
+/****************************************************************//**
+During merge, delete a record for a secondary index entry. */
+static
+void
+ibuf_delete(
+/*========*/
+	const dtuple_t*	entry,	/*!< in: entry */
+	buf_block_t*	block,	/*!< in/out: block */
+	dict_index_t*	index,	/*!< in: record descriptor */
+	mtr_t*		mtr)	/*!< in/out: mtr; must be committed
+				before latching any further pages */
+{
+	page_cur_t	page_cur;
+	ulint		low_match;
+
+	ut_ad(ibuf_inside(mtr));
+	ut_ad(dtuple_check_typed(entry));
+
+	low_match = page_cur_search(
+		block, index, entry, PAGE_CUR_LE, &page_cur);
+
+	if (low_match == dtuple_get_n_fields(entry)) {
+		page_zip_des_t*	page_zip= buf_block_get_page_zip(block);
+		page_t*		page	= buf_block_get_frame(block);
+		rec_t*		rec	= page_cur_get_rec(&page_cur);
+
+		/* TODO: the below should probably be a separate function,
+		it's a bastardized version of btr_cur_optimistic_delete. */
+
+		ulint		offsets_[REC_OFFS_NORMAL_SIZE];
+		ulint*		offsets	= offsets_;
+		mem_heap_t*	heap = NULL;
+		ulint		max_ins_size = 0;
+
+		rec_offs_init(offsets_);
+
+		offsets = rec_get_offsets(
+			rec, index, offsets, ULINT_UNDEFINED, &heap);
+
+		if (page_get_n_recs(page) <= 1
+		    || !(REC_INFO_DELETED_FLAG
+			 & rec_get_info_bits(rec, page_is_comp(page)))) {
+			/* Refuse to purge the last record or a
+			record that has not been marked for deletion. */
+			ut_print_timestamp(stderr);
+			fputs("  InnoDB: unable to purge a record\n",
+			      stderr);
+			fputs("InnoDB: tuple ", stderr);
+			dtuple_print(stderr, entry);
+			fputs("\n"
+			      "InnoDB: record ", stderr);
+			rec_print_new(stderr, rec, offsets);
+			fprintf(stderr, "\nspace %u offset %u"
+				" (%u records, index id %llu)\n"
+				"InnoDB: Submit a detailed bug report"
+				" to http://bugs.mysql.com\n",
+				(unsigned) buf_block_get_space(block),
+				(unsigned) buf_block_get_page_no(block),
+				(unsigned) page_get_n_recs(page),
+				(ulonglong) btr_page_get_index_id(page));
+
+			ut_ad(0);
+			return;
+		}
+
+		lock_update_delete(block, rec);
+
+		if (!page_zip) {
+			max_ins_size
+				= page_get_max_insert_size_after_reorganize(
+					page, 1);
+		}
+#ifdef UNIV_ZIP_DEBUG
+		ut_a(!page_zip || page_zip_validate(page_zip, page, index));
+#endif /* UNIV_ZIP_DEBUG */
+		page_cur_delete_rec(&page_cur, index, offsets, mtr);
+#ifdef UNIV_ZIP_DEBUG
+		ut_a(!page_zip || page_zip_validate(page_zip, page, index));
+#endif /* UNIV_ZIP_DEBUG */
+
+		if (page_zip) {
+			ibuf_update_free_bits_zip(block, mtr);
+		} else {
+			ibuf_update_free_bits_low(block, max_ins_size, mtr);
+		}
+
+		if (UNIV_LIKELY_NULL(heap)) {
+			mem_heap_free(heap);
+		}
+	} else {
+		/* The record must have been purged already. */
+	}
+}
+
+/*********************************************************************//**
+Restores insert buffer tree cursor position
+@return	TRUE if the position was restored; FALSE if not */
+static __attribute__((nonnull))
+ibool
+ibuf_restore_pos(
+/*=============*/
+	ulint		space,	/*!< in: space id */
+	ulint		page_no,/*!< in: index page number where the record
+				should belong */
+	const dtuple_t*	search_tuple,
+				/*!< in: search tuple for entries of page_no */
+	ulint		mode,	/*!< in: BTR_MODIFY_LEAF or BTR_MODIFY_TREE */
+	btr_pcur_t*	pcur,	/*!< in/out: persistent cursor whose
+				position is to be restored */
+	mtr_t*		mtr)	/*!< in/out: mini-transaction */
+{
+	ut_ad(mode == BTR_MODIFY_LEAF || mode == BTR_MODIFY_TREE);
+
+	if (btr_pcur_restore_position(mode, pcur, mtr)) {
+
+		return(TRUE);
+	}
+
+	if (fil_space_get_flags(space) == ULINT_UNDEFINED) {
+		/* The tablespace has been dropped.  It is possible
+		that another thread has deleted the insert buffer
+		entry.  Do not complain. */
+		ibuf_btr_pcur_commit_specify_mtr(pcur, mtr);
+	} else {
+		fprintf(stderr,
+			"InnoDB: ERROR: Submit the output to"
+			" http://bugs.mysql.com\n"
+			"InnoDB: ibuf cursor restoration fails!\n"
+			"InnoDB: ibuf record inserted to page %lu:%lu\n",
+			(ulong) space, (ulong) page_no);
+		fflush(stderr);
+
+		rec_print_old(stderr, btr_pcur_get_rec(pcur));
+		rec_print_old(stderr, pcur->old_rec);
+		dtuple_print(stderr, search_tuple);
+
+		rec_print_old(stderr,
+			      page_rec_get_next(btr_pcur_get_rec(pcur)));
+		fflush(stderr);
+
+		ibuf_btr_pcur_commit_specify_mtr(pcur, mtr);
+		ut_ad(0);
+	}
+
+	return(FALSE);
+}
+
+/*********************************************************************//**
+Deletes from ibuf the record on which pcur is positioned. If we have to
+resort to a pessimistic delete, this function commits mtr and closes
+the cursor.
+@return	TRUE if mtr was committed and pcur closed in this operation */
+static __attribute__((warn_unused_result))
+ibool
+ibuf_delete_rec(
+/*============*/
+	ulint		space,	/*!< in: space id */
+	ulint		page_no,/*!< in: index page number that the record
+				should belong to */
+	btr_pcur_t*	pcur,	/*!< in: pcur positioned on the record to
+				delete, having latch mode BTR_MODIFY_LEAF */
+	const dtuple_t*	search_tuple,
+				/*!< in: search tuple for entries of page_no */
+	mtr_t*		mtr)	/*!< in: mtr */
+{
+	ibool		success;
+	page_t*		root;
+	dberr_t		err;
+
+	ut_ad(ibuf_inside(mtr));
+	ut_ad(page_rec_is_user_rec(btr_pcur_get_rec(pcur)));
+	ut_ad(ibuf_rec_get_page_no(mtr, btr_pcur_get_rec(pcur)) == page_no);
+	ut_ad(ibuf_rec_get_space(mtr, btr_pcur_get_rec(pcur)) == space);
+
+#if defined UNIV_DEBUG || defined UNIV_IBUF_DEBUG
+	if (ibuf_debug == 2) {
+		/* Inject a fault (crash). We do this before trying
+		optimistic delete, because a pessimistic delete in the
+		change buffer would require a larger test case. */
+
+		/* Flag the buffered record as processed, to avoid
+		an assertion failure after crash recovery. */
+		btr_cur_set_deleted_flag_for_ibuf(
+			btr_pcur_get_rec(pcur), NULL, TRUE, mtr);
+		ibuf_mtr_commit(mtr);
+		log_write_up_to(LSN_MAX, LOG_WAIT_ALL_GROUPS, TRUE);
+		DBUG_SUICIDE();
+	}
+#endif /* UNIV_DEBUG || UNIV_IBUF_DEBUG */
+
+	success = btr_cur_optimistic_delete(btr_pcur_get_btr_cur(pcur),
+					    0, mtr);
+
+	if (success) {
+		if (page_is_empty(btr_pcur_get_page(pcur))) {
+			/* If a B-tree page is empty, it must be the root page
+			and the whole B-tree must be empty. InnoDB does not
+			allow empty B-tree pages other than the root. */
+			root = btr_pcur_get_page(pcur);
+
+			ut_ad(page_get_space_id(root) == IBUF_SPACE_ID);
+			ut_ad(page_get_page_no(root)
+			      == FSP_IBUF_TREE_ROOT_PAGE_NO);
+
+			/* ibuf->empty is protected by the root page latch.
+			Before the deletion, it had to be FALSE. */
+			ut_ad(!ibuf->empty);
+			ibuf->empty = true;
+		}
+
+#ifdef UNIV_IBUF_COUNT_DEBUG
+		fprintf(stderr,
+			"Decrementing ibuf count of space %lu page %lu\n"
+			"from %lu by 1\n", space, page_no,
+			ibuf_count_get(space, page_no));
+		ibuf_count_set(space, page_no,
+			       ibuf_count_get(space, page_no) - 1);
+#endif
+		return(FALSE);
+	}
+
+	ut_ad(page_rec_is_user_rec(btr_pcur_get_rec(pcur)));
+	ut_ad(ibuf_rec_get_page_no(mtr, btr_pcur_get_rec(pcur)) == page_no);
+	ut_ad(ibuf_rec_get_space(mtr, btr_pcur_get_rec(pcur)) == space);
+
+	/* We have to resort to a pessimistic delete from ibuf.
+	Delete-mark the record so that it will not be applied again,
+	in case the server crashes before the pessimistic delete is
+	made persistent. */
+	btr_cur_set_deleted_flag_for_ibuf(
+		btr_pcur_get_rec(pcur), NULL, TRUE, mtr);
+
+	btr_pcur_store_position(pcur, mtr);
+	ibuf_btr_pcur_commit_specify_mtr(pcur, mtr);
+
+	ibuf_mtr_start(mtr);
+	mutex_enter(&ibuf_mutex);
+
+	if (!ibuf_restore_pos(space, page_no, search_tuple,
+			      BTR_MODIFY_TREE, pcur, mtr)) {
+
+		mutex_exit(&ibuf_mutex);
+		ut_ad(mtr->state == MTR_COMMITTED);
+		goto func_exit;
+	}
+
+	root = ibuf_tree_root_get(mtr);
+
+	btr_cur_pessimistic_delete(&err, TRUE, btr_pcur_get_btr_cur(pcur), 0,
+				   RB_NONE, mtr);
+	ut_a(err == DB_SUCCESS);
+
+#ifdef UNIV_IBUF_COUNT_DEBUG
+	ibuf_count_set(space, page_no, ibuf_count_get(space, page_no) - 1);
+#endif
+	ibuf_size_update(root, mtr);
+	mutex_exit(&ibuf_mutex);
+
+	ibuf->empty = page_is_empty(root);
+	ibuf_btr_pcur_commit_specify_mtr(pcur, mtr);
+
+func_exit:
+	ut_ad(mtr->state == MTR_COMMITTED);
+	btr_pcur_close(pcur);
+
+	return(TRUE);
+}
+
+/*********************************************************************//**
+When an index page is read from a disk to the buffer pool, this function
+applies any buffered operations to the page and deletes the entries from the
+insert buffer. If the page is not read, but created in the buffer pool, this
+function deletes its buffered entries from the insert buffer; there can
+exist entries for such a page if the page belonged to an index which
+subsequently was dropped. */
+UNIV_INTERN
+void
+ibuf_merge_or_delete_for_page(
+/*==========================*/
+	buf_block_t*	block,	/*!< in: if page has been read from
+				disk, pointer to the page x-latched,
+				else NULL */
+	ulint		space,	/*!< in: space id of the index page */
+	ulint		page_no,/*!< in: page number of the index page */
+	ulint		zip_size,/*!< in: compressed page size in bytes,
+				or 0 */
+	ibool		update_ibuf_bitmap)/*!< in: normally this is set
+				to TRUE, but if we have deleted or are
+				deleting the tablespace, then we
+				naturally do not want to update a
+				non-existent bitmap page */
+{
+	mem_heap_t*	heap;
+	btr_pcur_t	pcur;
+	dtuple_t*	search_tuple;
+#ifdef UNIV_IBUF_DEBUG
+	ulint		volume			= 0;
+#endif
+	page_zip_des_t*	page_zip		= NULL;
+	ibool		tablespace_being_deleted = FALSE;
+	ibool		corruption_noticed	= FALSE;
+	mtr_t		mtr;
+
+	/* Counts for merged & discarded operations. */
+	ulint		mops[IBUF_OP_COUNT];
+	ulint		dops[IBUF_OP_COUNT];
+
+	ut_ad(!block || buf_block_get_space(block) == space);
+	ut_ad(!block || buf_block_get_page_no(block) == page_no);
+	ut_ad(!block || buf_block_get_zip_size(block) == zip_size);
+	ut_ad(!block || buf_block_get_io_fix(block) == BUF_IO_READ);
+
+	if (srv_force_recovery >= SRV_FORCE_NO_IBUF_MERGE
+	    || trx_sys_hdr_page(space, page_no)) {
+		return;
+	}
+
+	/* We cannot refer to zip_size in the following, because
+	zip_size is passed as ULINT_UNDEFINED (it is unknown) when
+	buf_read_ibuf_merge_pages() is merging (discarding) changes
+	for a dropped tablespace.  When block != NULL or
+	update_ibuf_bitmap is specified, the zip_size must be known.
+	That is why we will repeat the check below, with zip_size in
+	place of 0.  Passing zip_size as 0 assumes that the
+	uncompressed page size always is a power-of-2 multiple of the
+	compressed page size. */
+
+	if (ibuf_fixed_addr_page(space, 0, page_no)
+	    || fsp_descr_page(0, page_no)) {
+		return;
+	}
+
+	if (UNIV_LIKELY(update_ibuf_bitmap)) {
+		ut_a(ut_is_2pow(zip_size));
+
+		if (ibuf_fixed_addr_page(space, zip_size, page_no)
+		    || fsp_descr_page(zip_size, page_no)) {
+			return;
+		}
+
+		/* If the following returns FALSE, we get the counter
+		incremented, and must decrement it when we leave this
+		function. When the counter is > 0, that prevents tablespace
+		from being dropped. */
+
+		tablespace_being_deleted = fil_inc_pending_ops(space, true);
+
+		if (UNIV_UNLIKELY(tablespace_being_deleted)) {
+			/* Do not try to read the bitmap page from space;
+			just delete the ibuf records for the page */
+
+			block = NULL;
+			update_ibuf_bitmap = FALSE;
+		} else {
+			page_t*	bitmap_page;
+			ulint	bitmap_bits;
+
+			ibuf_mtr_start(&mtr);
+
+			bitmap_page = ibuf_bitmap_get_map_page(
+				space, page_no, zip_size, &mtr);
+			bitmap_bits = ibuf_bitmap_page_get_bits(
+				bitmap_page, page_no, zip_size,
+				IBUF_BITMAP_BUFFERED, &mtr);
+
+			ibuf_mtr_commit(&mtr);
+
+			if (!bitmap_bits) {
+				/* No inserts buffered for this page */
+
+				if (!tablespace_being_deleted) {
+					fil_decr_pending_ops(space);
+				}
+
+				return;
+			}
+		}
+	} else if (block
+		   && (ibuf_fixed_addr_page(space, zip_size, page_no)
+		      || fsp_descr_page(zip_size, page_no))) {
+
+		return;
+	}
+
+	heap = mem_heap_create(512);
+
+	search_tuple = ibuf_search_tuple_build(space, page_no, heap);
+
+	if (block) {
+		/* Move the ownership of the x-latch on the page to this OS
+		thread, so that we can acquire a second x-latch on it. This
+		is needed for the insert operations to the index page to pass
+		the debug checks. */
+
+		rw_lock_x_lock_move_ownership(&(block->lock));
+		page_zip = buf_block_get_page_zip(block);
+
+		if (UNIV_UNLIKELY(fil_page_get_type(block->frame)
+				  != FIL_PAGE_INDEX)
+		    || UNIV_UNLIKELY(!page_is_leaf(block->frame))) {
+
+			page_t*	bitmap_page;
+
+			corruption_noticed = TRUE;
+
+			ut_print_timestamp(stderr);
+
+			ibuf_mtr_start(&mtr);
+
+			fputs("  InnoDB: Dump of the ibuf bitmap page:\n",
+			      stderr);
+
+			bitmap_page = ibuf_bitmap_get_map_page(space, page_no,
+							       zip_size, &mtr);
+			buf_page_print(bitmap_page, 0,
+				       BUF_PAGE_PRINT_NO_CRASH);
+			ibuf_mtr_commit(&mtr);
+
+			fputs("\nInnoDB: Dump of the page:\n", stderr);
+
+			buf_page_print(block->frame, 0,
+				       BUF_PAGE_PRINT_NO_CRASH);
+
+			fprintf(stderr,
+				"InnoDB: Error: corruption in the tablespace."
+				" Bitmap shows insert\n"
+				"InnoDB: buffer records to page n:o %lu"
+				" though the page\n"
+				"InnoDB: type is %lu, which is"
+				" not an index leaf page!\n"
+				"InnoDB: We try to resolve the problem"
+				" by skipping the insert buffer\n"
+				"InnoDB: merge for this page."
+				" Please run CHECK TABLE on your tables\n"
+				"InnoDB: to determine if they are corrupt"
+				" after this.\n\n"
+				"InnoDB: Please submit a detailed bug report"
+				" to http://bugs.mysql.com\n\n",
+				(ulong) page_no,
+				(ulong)
+				fil_page_get_type(block->frame));
+			ut_ad(0);
+		}
+	}
+
+	memset(mops, 0, sizeof(mops));
+	memset(dops, 0, sizeof(dops));
+
+loop:
+	ibuf_mtr_start(&mtr);
+
+	/* Position pcur in the insert buffer at the first entry for this
+	index page */
+	btr_pcur_open_on_user_rec(
+		ibuf->index, search_tuple, PAGE_CUR_GE, BTR_MODIFY_LEAF,
+		&pcur, &mtr);
+
+	if (block) {
+		ibool success;
+
+		success = buf_page_get_known_nowait(
+			RW_X_LATCH, block,
+			BUF_KEEP_OLD, __FILE__, __LINE__, &mtr);
+
+		ut_a(success);
+
+		/* This is a user page (secondary index leaf page),
+		but we pretend that it is a change buffer page in
+		order to obey the latching order. This should be OK,
+		because buffered changes are applied immediately while
+		the block is io-fixed. Other threads must not try to
+		latch an io-fixed block. */
+		buf_block_dbg_add_level(block, SYNC_IBUF_TREE_NODE);
+	}
+
+	if (!btr_pcur_is_on_user_rec(&pcur)) {
+		ut_ad(btr_pcur_is_after_last_in_tree(&pcur, &mtr));
+
+		goto reset_bit;
+	}
+
+	for (;;) {
+		rec_t*	rec;
+
+		ut_ad(btr_pcur_is_on_user_rec(&pcur));
+
+		rec = btr_pcur_get_rec(&pcur);
+
+		/* Check if the entry is for this index page */
+		if (ibuf_rec_get_page_no(&mtr, rec) != page_no
+		    || ibuf_rec_get_space(&mtr, rec) != space) {
+
+			if (block) {
+				page_header_reset_last_insert(
+					block->frame, page_zip, &mtr);
+			}
+
+			goto reset_bit;
+		}
+
+		if (UNIV_UNLIKELY(corruption_noticed)) {
+			fputs("InnoDB: Discarding record\n ", stderr);
+			rec_print_old(stderr, rec);
+			fputs("\nInnoDB: from the insert buffer!\n\n", stderr);
+		} else if (block && !rec_get_deleted_flag(rec, 0)) {
+			/* Now we have at pcur a record which should be
+			applied on the index page; NOTE that the call below
+			copies pointers to fields in rec, and we must
+			keep the latch to the rec page until the
+			insertion is finished! */
+			dtuple_t*	entry;
+			trx_id_t	max_trx_id;
+			dict_index_t*	dummy_index;
+			ibuf_op_t	op = ibuf_rec_get_op_type(&mtr, rec);
+
+			max_trx_id = page_get_max_trx_id(page_align(rec));
+			page_update_max_trx_id(block, page_zip, max_trx_id,
+					       &mtr);
+
+			ut_ad(page_validate(page_align(rec), ibuf->index));
+
+			entry = ibuf_build_entry_from_ibuf_rec(
+				&mtr, rec, heap, &dummy_index);
+
+			ut_ad(page_validate(block->frame, dummy_index));
+
+			switch (op) {
+				ibool	success;
+			case IBUF_OP_INSERT:
+#ifdef UNIV_IBUF_DEBUG
+				volume += rec_get_converted_size(
+					dummy_index, entry, 0);
+
+				volume += page_dir_calc_reserved_space(1);
+
+				ut_a(volume <= 4 * UNIV_PAGE_SIZE
+					/ IBUF_PAGE_SIZE_PER_FREE_SPACE);
+#endif
+				ibuf_insert_to_index_page(
+					entry, block, dummy_index, &mtr);
+				break;
+
+			case IBUF_OP_DELETE_MARK:
+				ibuf_set_del_mark(
+					entry, block, dummy_index, &mtr);
+				break;
+
+			case IBUF_OP_DELETE:
+				ibuf_delete(entry, block, dummy_index, &mtr);
+				/* Because ibuf_delete() will latch an
+				insert buffer bitmap page, commit mtr
+				before latching any further pages.
+				Store and restore the cursor position. */
+				ut_ad(rec == btr_pcur_get_rec(&pcur));
+				ut_ad(page_rec_is_user_rec(rec));
+				ut_ad(ibuf_rec_get_page_no(&mtr, rec)
+				      == page_no);
+				ut_ad(ibuf_rec_get_space(&mtr, rec) == space);
+
+				/* Mark the change buffer record processed,
+				so that it will not be merged again in case
+				the server crashes between the following
+				mtr_commit() and the subsequent mtr_commit()
+				of deleting the change buffer record. */
+
+				btr_cur_set_deleted_flag_for_ibuf(
+					btr_pcur_get_rec(&pcur), NULL,
+					TRUE, &mtr);
+
+				btr_pcur_store_position(&pcur, &mtr);
+				ibuf_btr_pcur_commit_specify_mtr(&pcur, &mtr);
+
+				ibuf_mtr_start(&mtr);
+
+				success = buf_page_get_known_nowait(
+					RW_X_LATCH, block,
+					BUF_KEEP_OLD,
+					__FILE__, __LINE__, &mtr);
+				ut_a(success);
+
+				/* This is a user page (secondary
+				index leaf page), but it should be OK
+				to use too low latching order for it,
+				as the block is io-fixed. */
+				buf_block_dbg_add_level(
+					block, SYNC_IBUF_TREE_NODE);
+
+				if (!ibuf_restore_pos(space, page_no,
+						      search_tuple,
+						      BTR_MODIFY_LEAF,
+						      &pcur, &mtr)) {
+
+					ut_ad(mtr.state == MTR_COMMITTED);
+					mops[op]++;
+					ibuf_dummy_index_free(dummy_index);
+					goto loop;
+				}
+
+				break;
+			default:
+				ut_error;
+			}
+
+			mops[op]++;
+
+			ibuf_dummy_index_free(dummy_index);
+		} else {
+			dops[ibuf_rec_get_op_type(&mtr, rec)]++;
+		}
+
+		/* Delete the record from ibuf */
+		if (ibuf_delete_rec(space, page_no, &pcur, search_tuple,
+				    &mtr)) {
+			/* Deletion was pessimistic and mtr was committed:
+			we start from the beginning again */
+
+			ut_ad(mtr.state == MTR_COMMITTED);
+			goto loop;
+		} else if (btr_pcur_is_after_last_on_page(&pcur)) {
+			ibuf_mtr_commit(&mtr);
+			btr_pcur_close(&pcur);
+
+			goto loop;
+		}
+	}
+
+reset_bit:
+	if (UNIV_LIKELY(update_ibuf_bitmap)) {
+		page_t*	bitmap_page;
+
+		bitmap_page = ibuf_bitmap_get_map_page(
+			space, page_no, zip_size, &mtr);
+
+		ibuf_bitmap_page_set_bits(
+			bitmap_page, page_no, zip_size,
+			IBUF_BITMAP_BUFFERED, FALSE, &mtr);
+
+		if (block) {
+			ulint old_bits = ibuf_bitmap_page_get_bits(
+				bitmap_page, page_no, zip_size,
+				IBUF_BITMAP_FREE, &mtr);
+
+			ulint new_bits = ibuf_index_page_calc_free(
+				zip_size, block);
+
+			if (old_bits != new_bits) {
+				ibuf_bitmap_page_set_bits(
+					bitmap_page, page_no, zip_size,
+					IBUF_BITMAP_FREE, new_bits, &mtr);
+			}
+		}
+	}
+
+	ibuf_mtr_commit(&mtr);
+	btr_pcur_close(&pcur);
+	mem_heap_free(heap);
+
+#ifdef HAVE_ATOMIC_BUILTINS
+	os_atomic_increment_ulint(&ibuf->n_merges, 1);
+	ibuf_add_ops(ibuf->n_merged_ops, mops);
+	ibuf_add_ops(ibuf->n_discarded_ops, dops);
+#else /* HAVE_ATOMIC_BUILTINS */
+	/* Protect our statistics keeping from race conditions */
+	mutex_enter(&ibuf_mutex);
+
+	ibuf->n_merges++;
+	ibuf_add_ops(ibuf->n_merged_ops, mops);
+	ibuf_add_ops(ibuf->n_discarded_ops, dops);
+
+	mutex_exit(&ibuf_mutex);
+#endif /* HAVE_ATOMIC_BUILTINS */
+
+	if (update_ibuf_bitmap && !tablespace_being_deleted) {
+
+		fil_decr_pending_ops(space);
+	}
+
+#ifdef UNIV_IBUF_COUNT_DEBUG
+	ut_a(ibuf_count_get(space, page_no) == 0);
+#endif
+}
+
+/*********************************************************************//**
+Deletes all entries in the insert buffer for a given space id. This is used
+in DISCARD TABLESPACE and IMPORT TABLESPACE.
+NOTE: this does not update the page free bitmaps in the space. The space will
+become CORRUPT when you call this function! */
+UNIV_INTERN
+void
+ibuf_delete_for_discarded_space(
+/*============================*/
+	ulint	space)	/*!< in: space id */
+{
+	mem_heap_t*	heap;
+	btr_pcur_t	pcur;
+	dtuple_t*	search_tuple;
+	const rec_t*	ibuf_rec;
+	ulint		page_no;
+	mtr_t		mtr;
+
+	/* Counts for discarded operations. */
+	ulint		dops[IBUF_OP_COUNT];
+
+	heap = mem_heap_create(512);
+
+	/* Use page number 0 to build the search tuple so that we get the
+	cursor positioned at the first entry for this space id */
+
+	search_tuple = ibuf_search_tuple_build(space, 0, heap);
+
+	memset(dops, 0, sizeof(dops));
+loop:
+	ibuf_mtr_start(&mtr);
+
+	/* Position pcur in the insert buffer at the first entry for the
+	space */
+	btr_pcur_open_on_user_rec(
+		ibuf->index, search_tuple, PAGE_CUR_GE, BTR_MODIFY_LEAF,
+		&pcur, &mtr);
+
+	if (!btr_pcur_is_on_user_rec(&pcur)) {
+		ut_ad(btr_pcur_is_after_last_in_tree(&pcur, &mtr));
+
+		goto leave_loop;
+	}
+
+	for (;;) {
+		ut_ad(btr_pcur_is_on_user_rec(&pcur));
+
+		ibuf_rec = btr_pcur_get_rec(&pcur);
+
+		/* Check if the entry is for this space */
+		if (ibuf_rec_get_space(&mtr, ibuf_rec) != space) {
+
+			goto leave_loop;
+		}
+
+		page_no = ibuf_rec_get_page_no(&mtr, ibuf_rec);
+
+		dops[ibuf_rec_get_op_type(&mtr, ibuf_rec)]++;
+
+		/* Delete the record from ibuf */
+		if (ibuf_delete_rec(space, page_no, &pcur, search_tuple,
+				    &mtr)) {
+			/* Deletion was pessimistic and mtr was committed:
+			we start from the beginning again */
+
+			ut_ad(mtr.state == MTR_COMMITTED);
+			goto loop;
+		}
+
+		if (btr_pcur_is_after_last_on_page(&pcur)) {
+			ibuf_mtr_commit(&mtr);
+			btr_pcur_close(&pcur);
+
+			goto loop;
+		}
+	}
+
+leave_loop:
+	ibuf_mtr_commit(&mtr);
+	btr_pcur_close(&pcur);
+
+#ifdef HAVE_ATOMIC_BUILTINS
+	ibuf_add_ops(ibuf->n_discarded_ops, dops);
+#else /* HAVE_ATOMIC_BUILTINS */
+	/* Protect our statistics keeping from race conditions */
+	mutex_enter(&ibuf_mutex);
+	ibuf_add_ops(ibuf->n_discarded_ops, dops);
+	mutex_exit(&ibuf_mutex);
+#endif /* HAVE_ATOMIC_BUILTINS */
+
+	mem_heap_free(heap);
+}
+
+/******************************************************************//**
+Looks if the insert buffer is empty.
+@return	true if empty */
+UNIV_INTERN
+bool
+ibuf_is_empty(void)
+/*===============*/
+{
+	bool		is_empty;
+	const page_t*	root;
+	mtr_t		mtr;
+
+	ibuf_mtr_start(&mtr);
+
+	mutex_enter(&ibuf_mutex);
+	root = ibuf_tree_root_get(&mtr);
+	mutex_exit(&ibuf_mutex);
+
+	is_empty = page_is_empty(root);
+	ut_a(is_empty == ibuf->empty);
+	ibuf_mtr_commit(&mtr);
+
+	return(is_empty);
+}
+
+/******************************************************************//**
+Prints info of ibuf. */
+UNIV_INTERN
+void
+ibuf_print(
+/*=======*/
+	FILE*	file)	/*!< in: file where to print */
+{
+#ifdef UNIV_IBUF_COUNT_DEBUG
+	ulint		i;
+	ulint		j;
+#endif
+
+	mutex_enter(&ibuf_mutex);
+
+	fprintf(file,
+		"Ibuf: size %lu, free list len %lu,"
+		" seg size %lu, %lu merges\n",
+		(ulong) ibuf->size,
+		(ulong) ibuf->free_list_len,
+		(ulong) ibuf->seg_size,
+		(ulong) ibuf->n_merges);
+
+	fputs("merged operations:\n ", file);
+	ibuf_print_ops(ibuf->n_merged_ops, file);
+
+	fputs("discarded operations:\n ", file);
+	ibuf_print_ops(ibuf->n_discarded_ops, file);
+
+#ifdef UNIV_IBUF_COUNT_DEBUG
+	for (i = 0; i < IBUF_COUNT_N_SPACES; i++) {
+		for (j = 0; j < IBUF_COUNT_N_PAGES; j++) {
+			ulint	count = ibuf_count_get(i, j);
+
+			if (count > 0) {
+				fprintf(stderr,
+					"Ibuf count for space/page %lu/%lu"
+					" is %lu\n",
+					(ulong) i, (ulong) j, (ulong) count);
+			}
+		}
+	}
+#endif /* UNIV_IBUF_COUNT_DEBUG */
+
+	mutex_exit(&ibuf_mutex);
+}
+
+/******************************************************************//**
+Checks the insert buffer bitmaps on IMPORT TABLESPACE.
+@return DB_SUCCESS or error code */
+UNIV_INTERN
+dberr_t
+ibuf_check_bitmap_on_import(
+/*========================*/
+	const trx_t*	trx,		/*!< in: transaction */
+	ulint		space_id)	/*!< in: tablespace identifier */
+{
+	ulint	zip_size;
+	ulint	page_size;
+	ulint	size;
+	ulint	page_no;
+
+	ut_ad(space_id);
+	ut_ad(trx->mysql_thd);
+
+	zip_size = fil_space_get_zip_size(space_id);
+
+	if (zip_size == ULINT_UNDEFINED) {
+		return(DB_TABLE_NOT_FOUND);
+	}
+
+	size = fil_space_get_size(space_id);
+
+	if (size == 0) {
+		return(DB_TABLE_NOT_FOUND);
+	}
+
+	mutex_enter(&ibuf_mutex);
+
+	page_size = zip_size ? zip_size : UNIV_PAGE_SIZE;
+
+	for (page_no = 0; page_no < size; page_no += page_size) {
+		mtr_t	mtr;
+		page_t*	bitmap_page;
+		ulint	i;
+
+		if (trx_is_interrupted(trx)) {
+			mutex_exit(&ibuf_mutex);
+			return(DB_INTERRUPTED);
+		}
+
+		mtr_start(&mtr);
+
+		mtr_set_log_mode(&mtr, MTR_LOG_NO_REDO);
+
+		ibuf_enter(&mtr);
+
+		bitmap_page = ibuf_bitmap_get_map_page(
+			space_id, page_no, zip_size, &mtr);
+
+		for (i = FSP_IBUF_BITMAP_OFFSET + 1; i < page_size; i++) {
+			const ulint	offset = page_no + i;
+
+			if (ibuf_bitmap_page_get_bits(
+				    bitmap_page, offset, zip_size,
+				    IBUF_BITMAP_IBUF, &mtr)) {
+
+				mutex_exit(&ibuf_mutex);
+				ibuf_exit(&mtr);
+				mtr_commit(&mtr);
+
+				ib_errf(trx->mysql_thd,
+					IB_LOG_LEVEL_ERROR,
+					 ER_INNODB_INDEX_CORRUPT,
+					 "Space %u page %u"
+					 " is wrongly flagged to belong to the"
+					 " insert buffer",
+					 (unsigned) space_id,
+					 (unsigned) offset);
+
+				return(DB_CORRUPTION);
+			}
+
+			if (ibuf_bitmap_page_get_bits(
+				    bitmap_page, offset, zip_size,
+				    IBUF_BITMAP_BUFFERED, &mtr)) {
+
+				ib_errf(trx->mysql_thd,
+					IB_LOG_LEVEL_WARN,
+					ER_INNODB_INDEX_CORRUPT,
+					"Buffered changes"
+					" for space %u page %u are lost",
+					(unsigned) space_id,
+					(unsigned) offset);
+
+				/* Tolerate this error, so that
+				slightly corrupted tables can be
+				imported and dumped.  Clear the bit. */
+				ibuf_bitmap_page_set_bits(
+					bitmap_page, offset, zip_size,
+					IBUF_BITMAP_BUFFERED, FALSE, &mtr);
+			}
+		}
+
+		ibuf_exit(&mtr);
+		mtr_commit(&mtr);
+	}
+
+	mutex_exit(&ibuf_mutex);
+	return(DB_SUCCESS);
+}
+#endif /* !UNIV_HOTBACKUP */