Insert buffer. More...

#include "univ.i"
#include "dict0mem.h"
#include "fsp0fsp.h"
#include "mtr0mtr.h"
#include "ibuf0types.h"
#include "ibuf0ibuf.ic"

Enumerations
enum	ibuf_op_t { IBUF_OP_INSERT = 0 , IBUF_OP_DELETE_MARK = 1 , IBUF_OP_DELETE = 2 , IBUF_OP_COUNT = 3 }

enum	ibuf_use_t { IBUF_USE_NONE = 0 , IBUF_USE_INSERT , IBUF_USE_DELETE_MARK , IBUF_USE_INSERT_DELETE_MARK , IBUF_USE_DELETE , IBUF_USE_ALL }
	Combinations of operations that can be buffered. More...

Functions
void	ibuf_init_at_db_start (void)
	Creates the insert buffer data structure at a database startup. More...

void	ibuf_max_size_update (ulint new_val)
	Updates the max_size value for ibuf. More...

void	ibuf_update_max_tablespace_id (void)
	Reads the biggest tablespace id from the high end of the insert buffer tree and updates the counter in fil_system. More...

static void	ibuf_mtr_start (mtr_t *mtr)
	Starts an insert buffer mini-transaction. More...

static void	ibuf_mtr_commit (mtr_t *mtr)
	Commits an insert buffer mini-transaction. More...

void	ibuf_bitmap_page_init (buf_block_t block, mtr_t mtr)
	Initializes an ibuf bitmap page. More...

void	ibuf_reset_free_bits (buf_block_t *block)
	Resets the free bits of the page in the ibuf bitmap. More...

static void	ibuf_update_free_bits_if_full (buf_block_t *block, ulint max_ins_size, ulint increase)
	Updates the free bits of an uncompressed page in the ibuf bitmap if there is not enough free on the page any more. More...

void	ibuf_update_free_bits_low (const buf_block_t block, ulint max_ins_size, mtr_t mtr)
	Updates the free bits for an uncompressed page to reflect the present state. More...

void	ibuf_update_free_bits_zip (buf_block_t block, mtr_t mtr)
	Updates the free bits for a compressed page to reflect the present state. More...

void	ibuf_update_free_bits_for_two_pages_low (buf_block_t block1, buf_block_t block2, mtr_t *mtr)
	Updates the free bits for the two pages to reflect the present state. More...

static bool	ibuf_should_try (dict_index_t *index, ulint ignore_sec_unique)
	A basic partial test if an insert to the insert buffer could be possible and recommended. More...

static bool	ibuf_inside (const mtr_t *mtr)
	Returns true if the current OS thread is performing an insert buffer routine. More...

static bool	ibuf_bitmap_page (const page_id_t &page_id, const page_size_t &page_size)
	Checks if a page address is an ibuf bitmap page (level 3 page) address. More...

bool	ibuf_page_low (const page_id_t &page_id, const page_size_t &page_size, bool x_latch, ut::Location location, mtr_t *mtr)
	Checks if a page is a level 2 or 3 page in the ibuf hierarchy of pages. More...

bool	ibuf_page (const page_id_t &page_id, const page_size_t &page_size, ut::Location location, mtr_t *mtr)
	Checks if a page is a level 2 or 3 page in the ibuf hierarchy of pages. More...

void	ibuf_free_excess_pages (void)
	Frees excess pages from the ibuf free list. More...

bool	ibuf_insert (ibuf_op_t op, const dtuple_t entry, dict_index_t index, const page_id_t &page_id, const page_size_t &page_size, que_thr_t *thr)
	Buffer an operation in the insert/delete buffer, instead of doing it directly to the disk page, if this is possible. More...

void	ibuf_merge_or_delete_for_page (buf_block_t block, const page_id_t &page_id, const page_size_t page_size, bool update_ibuf_bitmap)
	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. More...

void	ibuf_delete_for_discarded_space (space_id_t space)
	Deletes all entries in the insert buffer for a given space id. More...

ulint	ibuf_merge_in_background (bool full)
	Contract the change buffer by reading pages to the buffer pool. More...

ulint	ibuf_merge_space (space_id_t space)
	Contracts insert buffer trees by reading pages referring to space_id to the buffer pool. More...

byte *	ibuf_parse_bitmap_init (byte ptr, byte end_ptr, buf_block_t block, mtr_t mtr)
	Parses a redo log record of an ibuf bitmap page init. More...

bool	ibuf_is_empty (void)
	Looks if the insert buffer is empty. More...

void	ibuf_print (FILE *file)
	Prints info of ibuf. More...

ulint	ibuf_rec_get_counter (const rec_t *rec)
	in: ibuf record More...

bool	ibuf_rec_has_multi_value (const rec_t *rec)
	Determine if there is any multi-value field data on the change buffer record. More...

void	ibuf_close (void)
	Closes insert buffer and frees the data structures. More...

dberr_t	ibuf_check_bitmap_on_import (const trx_t *trx, space_id_t space_id)
	Checks the insert buffer bitmaps on IMPORT TABLESPACE. More...

void	ibuf_set_bitmap_for_bulk_load (buf_block_t *block, bool reset)
	Updates free bits and buffered bits for bulk loaded page. More...

Variables
constexpr uint32_t	CHANGE_BUFFER_DEFAULT_SIZE = 25
	Default value for maximum on-disk size of change buffer in terms of percentage of the buffer pool. More...

ulong	innodb_change_buffering
	Operations that can currently be buffered. More...

ibuf_t *	ibuf
	The insert buffer control structure. More...

constexpr uint32_t	IBUF_HEADER_PAGE_NO = FSP_IBUF_HEADER_PAGE_NO

constexpr uint32_t	IBUF_TREE_ROOT_PAGE_NO = FSP_IBUF_TREE_ROOT_PAGE_NO

constexpr uint32_t	IBUF_HEADER = PAGE_DATA

constexpr uint32_t	IBUF_TREE_SEG_HEADER = 0
	fseg header for ibuf tree More...

Detailed Description

Insert buffer.

Created 7/19/1997 Heikki Tuuri

Enumeration Type Documentation

◆ ibuf_op_t

enum ibuf_op_t

Enumerator
IBUF_OP_INSERT
IBUF_OP_DELETE_MARK
IBUF_OP_DELETE
IBUF_OP_COUNT

◆ ibuf_use_t

enum ibuf_use_t

Combinations of operations that can be buffered.

See also: innodb_change_buffering_names

Enumerator
IBUF_USE_NONE
IBUF_USE_INSERT
IBUF_USE_DELETE_MARK
IBUF_USE_INSERT_DELETE_MARK
IBUF_USE_DELETE
IBUF_USE_ALL

Function Documentation

◆ ibuf_bitmap_page()

static bool ibuf_bitmap_page	(	const page_id_t &	page_id,
		const page_size_t &	page_size
	)

inlinestatic

Checks if a page address is an ibuf bitmap page (level 3 page) address.

Parameters

[in]	page_id	page id
[in]	page_size	page size

Returns: true if a bitmap page

◆ ibuf_bitmap_page_init()

void ibuf_bitmap_page_init	(	buf_block_t *	block,
		mtr_t *	mtr
	)

Initializes an ibuf bitmap page.

Parameters

block	in: bitmap page
mtr	in: mtr

◆ ibuf_check_bitmap_on_import()

dberr_t ibuf_check_bitmap_on_import	(	const trx_t *	trx,
		space_id_t	space_id
	)

Checks the insert buffer bitmaps on IMPORT TABLESPACE.

Returns: DB_SUCCESS or error code in: tablespace identifier; DB_SUCCESS or error code

Parameters

trx	in: transaction
space_id	in: tablespace identifier

◆ ibuf_close()

void ibuf_close ( void )

Closes insert buffer and frees the data structures.

◆ ibuf_delete_for_discarded_space()

void ibuf_delete_for_discarded_space ( space_id_t space )

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! in: 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!

Parameters

space in: space id

◆ ibuf_free_excess_pages()

void ibuf_free_excess_pages ( void )

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.

◆ ibuf_init_at_db_start()

void ibuf_init_at_db_start ( void )

Creates the insert buffer data structure at a database startup.

◆ ibuf_insert()

bool ibuf_insert	(	ibuf_op_t	op,
		const dtuple_t *	entry,
		dict_index_t *	index,
		const page_id_t &	page_id,
		const page_size_t &	page_size,
		que_thr_t *	thr
	)

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.

Parameters

[in]	op	operation type
[in]	entry	index entry to insert
[in,out]	index	index where to insert
[in]	page_id	page id where to insert
[in]	page_size	page size
[in,out]	thr	query thread

Returns: true if success

◆ ibuf_inside()

static bool ibuf_inside ( const mtr_t * mtr )

inlinestatic

Returns true if the current OS thread is performing an insert buffer routine.

For instance, a read-ahead of non-ibuf pages is forbidden by threads that are executing an insert buffer routine.

Returns: true if inside an insert buffer routine in: mini-transaction

◆ ibuf_is_empty()

bool ibuf_is_empty ( void )

Looks if the insert buffer is empty.

Returns: true if empty

◆ ibuf_max_size_update()

void ibuf_max_size_update ( ulint new_val )

Updates the max_size value for ibuf.

in: new value in terms of percentage of the buffer pool size

Parameters

new_val in: new value in terms of percentage of the buffer pool size

◆ ibuf_merge_in_background()

ulint ibuf_merge_in_background ( bool full )

Contract the change buffer by reading pages to the buffer pool.

Parameters

[in] full If true, do a full contraction based on PCT_IO(100). If false, the size of contract batch is determined based on the current size of the change buffer.

Returns: 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

◆ ibuf_merge_or_delete_for_page()

void ibuf_merge_or_delete_for_page	(	buf_block_t *	block,
		const page_id_t &	page_id,
		const page_size_t *	page_size,
		bool	update_ibuf_bitmap
	)

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.

Parameters

[in,out]	block	if page has been read from disk, pointer to the page x-latched, else NULL
[in]	page_id	page id of the index page
[in]	update_ibuf_bitmap	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
[in]	page_size	page size

◆ ibuf_merge_space()

ulint ibuf_merge_space ( space_id_t space )

Contracts insert buffer trees by reading pages referring to space_id to the buffer pool.

Returns: number of pages merged. in: space id; number of pages merged.

Parameters

space in: tablespace id to merge

◆ ibuf_mtr_commit()

static void ibuf_mtr_commit ( mtr_t * mtr )

inlinestatic

Commits an insert buffer mini-transaction.

in/out: mini-transaction

◆ ibuf_mtr_start()

static void ibuf_mtr_start ( mtr_t * mtr )

inlinestatic

Starts an insert buffer mini-transaction.

out: mini-transaction

◆ ibuf_page()

bool ibuf_page	(	const page_id_t &	page_id,
		const page_size_t &	page_size,
		ut::Location	location,
		mtr_t *	mtr
	)

inline

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.

Parameters

[in]	page_id	Tablespace/page identifier
[in]	page_size	Page size
[in]	location	Location where requested
[in,out]	mtr	Mini-transaction or NULL

Returns: true if level 2 or level 3 page

◆ ibuf_page_low()

bool ibuf_page_low	(	const page_id_t &	page_id,
		const page_size_t &	page_size,
		bool	x_latch,
		ut::Location	location,
		mtr_t *	mtr
	)

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.

Parameters

[in]	page_id	page id
[in]	page_size	page size
[in]	x_latch	false if relaxed check (avoid latching the bitmap page)
[in]	location	Location where called
[in,out]	mtr	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.

Returns: true if level 2 or level 3 page

◆ ibuf_parse_bitmap_init()

byte * ibuf_parse_bitmap_init	(	byte *	ptr,
		byte *	end_ptr,
		buf_block_t *	block,
		mtr_t *	mtr
	)

Parses a redo log record of an ibuf bitmap page init.

Parameters

[in]	ptr	Buffer.
[in]	end_ptr	Buffer end.
[in]	block	Block or nullptr.
[in]	mtr	MTR or nullptr.

Returns: end of log record or NULL

◆ ibuf_print()

void ibuf_print ( FILE * file )

Prints info of ibuf.

in: file where to print

Parameters

file	in: file where to print

◆ ibuf_rec_get_counter()

ulint ibuf_rec_get_counter ( const rec_t * rec )

in: ibuf record

Returns: "counter" field, or ULINT_UNDEFINED if for some reason it can't be read

Parameters

rec	in: ibuf record

◆ ibuf_rec_has_multi_value()

bool ibuf_rec_has_multi_value ( const rec_t * rec )

Determine if there is any multi-value field data on the change buffer record.

Parameters

[in] rec ibuf record

Returns: true if there is any multi-value field in the record

◆ ibuf_reset_free_bits()

void ibuf_reset_free_bits ( buf_block_t * block )

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. in: index page; free bits are set to 0 if the index is a non-clustered non-unique, and page level is 0

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.

Parameters

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_bitmap_for_bulk_load()

void ibuf_set_bitmap_for_bulk_load	(	buf_block_t *	block,
		bool	reset
	)

Updates free bits and buffered bits for bulk loaded page.

Parameters

[in]	block	index page
[in]	reset	flag if reset free val

◆ ibuf_should_try()

static bool ibuf_should_try	(	dict_index_t *	index,
		ulint	ignore_sec_unique
	)

inlinestatic

A basic partial test if an insert to the insert buffer could be possible and recommended.

Parameters

[in]	index	index where to insert
[in]	ignore_sec_unique	if != 0, we should ignore UNIQUE constraint on a secondary index when we decide

◆ ibuf_update_free_bits_for_two_pages_low()

void ibuf_update_free_bits_for_two_pages_low	(	buf_block_t *	block1,
		buf_block_t *	block2,
		mtr_t *	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. in: mtr

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.

Parameters

block1	in: index page
block2	in: index page
mtr	in: mtr

◆ ibuf_update_free_bits_if_full()

static void ibuf_update_free_bits_if_full	(	buf_block_t *	block,
		ulint	max_ins_size,
		ulint	increase
	)

inlinestatic

Updates the free bits of an uncompressed page in the ibuf bitmap if there is not enough free on the page any more.

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 unsafe to increment the bits in a separately committed mini-transaction, because in crash recovery, the free bits could momentarily be set too high. It is only safe to use this function for decrementing the free bits. Should more free space become available, we must not update the free bits here, because that would break crash recovery.

Parameters

[in]	block	index page to which we have added new records; the free bits are updated if the index is non-clustered and non-unique and the page level is 0, and the page becomes fuller
[in]	max_ins_size	value of maximum insert size with reorganize before the latest operation performed to the page
[in]	increase	upper limit for the additional space used in the latest operation, if known, or ULINT_UNDEFINED

◆ ibuf_update_free_bits_low()

void ibuf_update_free_bits_low	(	const buf_block_t *	block,
		ulint	max_ins_size,
		mtr_t *	mtr
	)

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. in/out: mtr

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.

Parameters

block	in: index page
max_ins_size	in: value of maximum insert size with reorganize before the latest operation performed to the page
mtr	in/out: mtr

◆ ibuf_update_free_bits_zip()

void ibuf_update_free_bits_zip	(	buf_block_t *	block,
		mtr_t *	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. in/out: mtr

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.

Parameters

block	in/out: index page
mtr	in/out: mtr

◆ ibuf_update_max_tablespace_id()

void ibuf_update_max_tablespace_id ( void )

Reads the biggest tablespace id from the high end of the insert buffer tree and updates the counter in fil_system.

Variable Documentation

◆ CHANGE_BUFFER_DEFAULT_SIZE

constexpr uint32_t CHANGE_BUFFER_DEFAULT_SIZE = 25

constexpr

Default value for maximum on-disk size of change buffer in terms of percentage of the buffer pool.

◆ ibuf

ibuf_t* ibuf

extern

The insert buffer control structure.

◆ IBUF_HEADER

constexpr uint32_t IBUF_HEADER = PAGE_DATA

constexpr

◆ IBUF_HEADER_PAGE_NO

constexpr uint32_t IBUF_HEADER_PAGE_NO = FSP_IBUF_HEADER_PAGE_NO

constexpr

◆ IBUF_TREE_ROOT_PAGE_NO

constexpr uint32_t IBUF_TREE_ROOT_PAGE_NO = FSP_IBUF_TREE_ROOT_PAGE_NO

constexpr

◆ IBUF_TREE_SEG_HEADER

constexpr uint32_t IBUF_TREE_SEG_HEADER = 0

constexpr

fseg header for ibuf tree

◆ innodb_change_buffering

ulong innodb_change_buffering

extern

Operations that can currently be buffered.

Enumerations

Functions

Variables

Detailed Description

Enumeration Type Documentation

◆ ibuf_op_t

◆ ibuf_use_t

Function Documentation

◆ ibuf_bitmap_page()

◆ ibuf_bitmap_page_init()

◆ ibuf_check_bitmap_on_import()

◆ ibuf_close()

◆ ibuf_delete_for_discarded_space()

◆ ibuf_free_excess_pages()

◆ ibuf_init_at_db_start()

◆ ibuf_insert()

◆ ibuf_inside()

◆ ibuf_is_empty()

◆ ibuf_max_size_update()

◆ ibuf_merge_in_background()

◆ ibuf_merge_or_delete_for_page()

◆ ibuf_merge_space()

◆ ibuf_mtr_commit()

◆ ibuf_mtr_start()

◆ ibuf_page()

◆ ibuf_page_low()

◆ ibuf_parse_bitmap_init()

◆ ibuf_print()

◆ ibuf_rec_get_counter()

◆ ibuf_rec_has_multi_value()

◆ ibuf_reset_free_bits()

◆ ibuf_set_bitmap_for_bulk_load()

◆ ibuf_should_try()

◆ ibuf_update_free_bits_for_two_pages_low()

◆ ibuf_update_free_bits_if_full()

◆ ibuf_update_free_bits_low()

◆ ibuf_update_free_bits_zip()

◆ ibuf_update_max_tablespace_id()

Variable Documentation

◆ CHANGE_BUFFER_DEFAULT_SIZE

◆ ibuf

◆ IBUF_HEADER

◆ IBUF_HEADER_PAGE_NO

◆ IBUF_TREE_ROOT_PAGE_NO

◆ IBUF_TREE_SEG_HEADER

◆ innodb_change_buffering