MySQL 8.3.0
Source Code Documentation
ibuf0ibuf.h File Reference

Insert buffer. More...

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

Go to the source code of this file.

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...
 
byteibuf_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_tibuf
 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_idpage id
[in]page_sizepage 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
blockin: bitmap page
mtrin: 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
trxin: transaction
space_idin: 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
spacein: 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.

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]opoperation type
[in]entryindex entry to insert
[in,out]indexindex where to insert
[in]page_idpage id where to insert
[in]page_sizepage size
[in,out]thrquery 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_valin: 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]fullIf 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]blockif page has been read from disk, pointer to the page x-latched, else NULL
[in]page_idpage id of the index page
[in]update_ibuf_bitmapnormally 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_sizepage 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
spacein: 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_idTablespace/page identifier
[in]page_sizePage size
[in]locationLocation where requested
[in,out]mtrMini-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_idpage id
[in]page_sizepage size
[in]x_latchfalse if relaxed check (avoid latching the bitmap page)
[in]locationLocation where called
[in,out]mtrmtr 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]ptrBuffer.
[in]end_ptrBuffer end.
[in]blockBlock or nullptr.
[in]mtrMTR 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
filein: file where to print

◆ ibuf_rec_get_counter()

ulint ibuf_rec_get_counter ( const rec_t rec)

in: ibuf record

in: ibuf record

Returns
"counter" field, or ULINT_UNDEFINED if for some reason it can't be read
Parameters
recin: 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]recibuf 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
blockin: 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]blockindex page
[in]resetflag 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]indexindex where to insert
[in]ignore_sec_uniqueif != 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
block1in: index page
block2in: index page
mtrin: 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]blockindex 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_sizevalue of maximum insert size with reorganize before the latest operation performed to the page
[in]increaseupper 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
blockin: index page
max_ins_sizein: value of maximum insert size with reorganize before the latest operation performed to the page
mtrin/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
blockin/out: index page
mtrin/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.