#include "mtr0mtr.h"
#include "buf0flu.h"
#include "buf0lru.h"
#include "buf0rea.h"

Include dependency graph for buf0buf.ic:

This graph shows which files directly or indirectly include this file:

Data Structures
struct	buf_chunk_t

Functions
UNIV_INLINE ulint	buf_pool_get_curr_size (void)
UNIV_INLINE ulint	buf_pool_index (const buf_pool_t *buf_pool)
UNIV_INLINE buf_pool_t *	buf_pool_from_bpage (const buf_page_t *bpage)
UNIV_INLINE buf_pool_t *	buf_pool_from_block (const buf_block_t *block)
UNIV_INLINE ulint	buf_pool_get_n_pages (void)
UNIV_INLINE ulint	buf_page_get_freed_page_clock (const buf_page_t *bpage)
UNIV_INLINE ulint	buf_block_get_freed_page_clock (const buf_block_t *block)
UNIV_INLINE ibool	buf_page_peek_if_young (const buf_page_t *bpage)
UNIV_INLINE ibool	buf_page_peek_if_too_old (const buf_page_t *bpage)
UNIV_INLINE enum buf_page_state	buf_page_get_state (const buf_page_t *bpage)
UNIV_INLINE enum buf_page_state	buf_block_get_state (const buf_block_t *block)
UNIV_INLINE void	buf_page_set_state (buf_page_t *bpage, enum buf_page_state state)
UNIV_INLINE void	buf_block_set_state (buf_block_t *block, enum buf_page_state state)
UNIV_INLINE ibool	buf_page_in_file (const buf_page_t *bpage)
UNIV_INLINE ibool	buf_page_belongs_to_unzip_LRU (const buf_page_t *bpage)
UNIV_INLINE ib_mutex_t *	buf_page_get_mutex (const buf_page_t *bpage)
UNIV_INLINE buf_flush_t	buf_page_get_flush_type (const buf_page_t *bpage)
UNIV_INLINE void	buf_page_set_flush_type (buf_page_t *bpage, buf_flush_t flush_type)
UNIV_INLINE void	buf_block_set_file_page (buf_block_t *block, ulint space, ulint page_no)
UNIV_INLINE enum buf_io_fix	buf_page_get_io_fix (const buf_page_t *bpage)
UNIV_INLINE enum buf_io_fix	buf_block_get_io_fix (const buf_block_t *block)
UNIV_INLINE void	buf_page_set_io_fix (buf_page_t *bpage, enum buf_io_fix io_fix)
UNIV_INLINE void	buf_block_set_io_fix (buf_block_t *block, enum buf_io_fix io_fix)
UNIV_INLINE void	buf_page_set_sticky (buf_page_t *bpage)
UNIV_INLINE void	buf_page_unset_sticky (buf_page_t *bpage)
UNIV_INLINE ibool	buf_page_can_relocate (const buf_page_t *bpage)
UNIV_INLINE ibool	buf_page_is_old (const buf_page_t *bpage)
UNIV_INLINE void	buf_page_set_old (buf_page_t *bpage, ibool old)
UNIV_INLINE unsigned	buf_page_is_accessed (const buf_page_t *bpage)
UNIV_INLINE void	buf_page_set_accessed (buf_page_t *bpage)
UNIV_INLINE buf_block_t *	buf_page_get_block (buf_page_t *bpage)
UNIV_INLINE buf_frame_t *	buf_block_get_frame (const buf_block_t *block)
UNIV_INLINE ulint	buf_page_get_space (const buf_page_t *bpage)
UNIV_INLINE ulint	buf_block_get_space (const buf_block_t *block)
UNIV_INLINE ulint	buf_page_get_page_no (const buf_page_t *bpage)
UNIV_INLINE buf_frame_t *	buf_frame_align (byte *ptr)
UNIV_INLINE ulint	buf_block_get_page_no (const buf_block_t *block)
UNIV_INLINE ulint	buf_page_get_zip_size (const buf_page_t *bpage)
UNIV_INLINE ulint	buf_block_get_zip_size (const buf_block_t *block)
UNIV_INLINE const page_zip_des_t *	buf_frame_get_page_zip (const byte *ptr)
UNIV_INLINE void	buf_ptr_get_fsp_addr (const void ptr, ulint space, fil_addr_t *addr)
UNIV_INLINE ulint	buf_block_get_lock_hash_val (const buf_block_t *block)
UNIV_INLINE buf_page_t *	buf_page_alloc_descriptor (void)
UNIV_INLINE void	buf_page_free_descriptor (buf_page_t *bpage)
UNIV_INLINE void	buf_block_free (buf_block_t *block)
UNIV_INLINE byte *	buf_frame_copy (byte buf, const buf_frame_t frame)
UNIV_INLINE ulint	buf_page_address_fold (ulint space, ulint offset)
UNIV_INLINE lsn_t	buf_page_get_newest_modification (const buf_page_t *bpage)
UNIV_INLINE void	buf_block_modify_clock_inc (buf_block_t *block)
UNIV_INLINE ib_uint64_t	buf_block_get_modify_clock (buf_block_t *block)
UNIV_INLINE void	buf_block_fix (buf_block_t *block)
UNIV_INLINE void	buf_block_buf_fix_inc_func (const char file, ulint line, buf_block_t block)
UNIV_INLINE void	buf_block_unfix (buf_block_t *block)
UNIV_INLINE void	buf_block_buf_fix_dec (buf_block_t *block)
UNIV_INLINE buf_pool_t *	buf_pool_get (ulint space, ulint offset)
UNIV_INLINE buf_pool_t *	buf_pool_from_array (ulint index)
UNIV_INLINE buf_page_t *	buf_page_hash_get_low (buf_pool_t *buf_pool, ulint space, ulint offset, ulint fold)
UNIV_INLINE buf_page_t *	buf_page_hash_get_locked (buf_pool_t buf_pool, ulint space, ulint offset, rw_lock_t *lock, ulint lock_mode, bool watch)
UNIV_INLINE buf_block_t *	buf_block_hash_get_locked (buf_pool_t buf_pool, ulint space, ulint offset, rw_lock_t *lock, ulint lock_mode)
UNIV_INLINE ibool	buf_page_peek (ulint space, ulint offset)
UNIV_INLINE void	buf_page_release_zip (buf_page_t *bpage)
UNIV_INLINE void	buf_page_release (buf_block_t *block, ulint rw_latch)
UNIV_INLINE void	buf_block_dbg_add_level (buf_block_t *block, ulint level)
UNIV_INLINE void	buf_pool_mutex_enter_all (void)
UNIV_INLINE void	buf_pool_mutex_exit_all (void)
UNIV_INLINE buf_block_t *	buf_get_nth_chunk_block (const buf_pool_t buf_pool, ulint n, ulint chunk_size)

Detailed Description

The database buffer buf_pool

Created 11/5/1995 Heikki Tuuri

Function Documentation

UNIV_INLINE void buf_block_buf_fix_dec ( buf_block_t * block )

Decrements the bufferfix count.

Parameters

block in/out: block to bufferunfix

UNIV_INLINE void buf_block_buf_fix_inc_func	(	const char *	file,
		ulint	line,
		buf_block_t *	block
	)

Increments the bufferfix count.

Parameters

file	in: file name
line	in: line
block	in/out: block to bufferfix

UNIV_INLINE void buf_block_dbg_add_level	(	buf_block_t *	block,
		ulint	level
	)

Adds latch level info for the rw-lock protecting the buffer frame. This should be called in the debug version after a successful latching of a page if we know the latching order level of the acquired latch.

Parameters

block	in: buffer page where we have acquired latch
level	in: latching order level

UNIV_INLINE void buf_block_fix ( buf_block_t * block )

Increments the bufferfix count.

Parameters

block in/out: block to bufferfix

UNIV_INLINE void buf_block_free ( buf_block_t * block )

Frees a buffer block which does not contain a file page.

Parameters

block in, own: block to be freed

UNIV_INLINE buf_frame_t* buf_block_get_frame ( const buf_block_t * block )

Gets a pointer to the memory frame of a block.

Returns: pointer to the frame

Parameters

block in: pointer to the control block

UNIV_INLINE ulint buf_block_get_freed_page_clock ( const buf_block_t * block )

Reads the freed_page_clock of a buffer block.

Returns: freed_page_clock

Parameters

block in: block

UNIV_INLINE enum buf_io_fix buf_block_get_io_fix ( const buf_block_t * block )

Gets the io_fix state of a block.

Returns: io_fix state

Parameters

block in: pointer to the control block

UNIV_INLINE ulint buf_block_get_lock_hash_val ( const buf_block_t * block )

Gets the hash value of the page the pointer is pointing to. This can be used in searches in the lock hash table.

Returns: lock hash value

Parameters

block in: block

UNIV_INLINE ib_uint64_t buf_block_get_modify_clock ( buf_block_t * block )

Returns the value of the modify clock. The caller must have an s-lock or x-lock on the block.

Returns: value

Parameters

block in: block

UNIV_INLINE ulint buf_block_get_page_no ( const buf_block_t * block )

Gets the page number of a block.

Returns: page number

Parameters

block in: pointer to the control block

UNIV_INLINE ulint buf_block_get_space ( const buf_block_t * block )

Gets the space id of a block.

Returns: space id

Parameters

block in: pointer to the control block

UNIV_INLINE enum buf_page_state buf_block_get_state ( const buf_block_t * block )

Gets the state of a block.

Returns: state

Parameters

block in: pointer to the control block

UNIV_INLINE ulint buf_block_get_zip_size ( const buf_block_t * block )

Gets the compressed page size of a block.

Returns: compressed page size, or 0

Parameters

block in: pointer to the control block

UNIV_INLINE buf_block_t* buf_block_hash_get_locked	(	buf_pool_t *	buf_pool,
		ulint	space,
		ulint	offset,
		rw_lock_t **	lock,
		ulint	lock_mode
	)

Returns the control block of a file page, NULL if not found. If the block is found and lock is not NULL then the appropriate page_hash lock is acquired in the specified lock mode. Otherwise, mode value is ignored. It is up to the caller to release the lock. If the block is found and the lock is NULL then the page_hash lock is released by this function.

Returns: block, NULL if not found

Parameters

buf_pool	out: pointer to the bpage, or NULL; if NULL, hash_lock is also NULL. buffer pool instance
space	in: space id
offset	in: page number
lock	in/out: lock of the page hash acquired if bpage is found. NULL otherwise. If NULL is passed then the hash_lock is released by this function
lock_mode	in: RW_LOCK_EX or RW_LOCK_SHARED. Ignored if lock == NULL

UNIV_INLINE void buf_block_modify_clock_inc ( buf_block_t * block )

Increments the modify clock of a frame by 1. The caller must (1) own the buf_pool mutex and block bufferfix count has to be zero, (2) or own an x-lock on the block.

Parameters

block in: block

UNIV_INLINE void buf_block_set_file_page	(	buf_block_t *	block,
		ulint	space,
		ulint	page_no
	)

Map a block to a file page.

Parameters

block	in/out: pointer to control block
space	in: tablespace id
page_no	in: page number

UNIV_INLINE void buf_block_set_io_fix	(	buf_block_t *	block,
		enum buf_io_fix	io_fix
	)

Sets the io_fix state of a block.

Parameters

block	in/out: control block
io_fix	in: io_fix state

UNIV_INLINE void buf_block_set_state	(	buf_block_t *	block,
		enum buf_page_state	state
	)

Sets the state of a block.

Parameters

block	in/out: pointer to control block
state	in: state

UNIV_INLINE void buf_block_unfix ( buf_block_t * block )

Decrements the bufferfix count.

Parameters

block in/out: block to bufferunfix

UNIV_INLINE byte* buf_frame_copy	(	byte *	buf,
		const buf_frame_t *	frame
	)

Copies contents of a buffer frame to a given buffer.

Returns: buf

Parameters

buf	in: buffer to copy to
frame	in: buffer frame

UNIV_INLINE const page_zip_des_t* buf_frame_get_page_zip ( const byte * ptr )

Gets the compressed page descriptor corresponding to an uncompressed page if applicable.

Returns: compressed page descriptor, or NULL

Parameters

ptr	in: pointer to the page

UNIV_INLINE buf_block_t* buf_get_nth_chunk_block	(	const buf_pool_t *	buf_pool,
		ulint	n,
		ulint *	chunk_size
	)

Get the nth chunk's buffer block in the specified buffer pool.

Returns: the nth chunk's buffer block.

Parameters

buf_pool	in: buffer pool instance
n	in: nth chunk in the buffer pool
chunk_size	in: chunk size

UNIV_INLINE ulint buf_page_address_fold	(	ulint	space,
		ulint	offset
	)

Calculates a folded value of a file page address to use in the page hash table.

Returns: the folded value

Parameters

space	in: space id
offset	in: offset of the page within space

UNIV_INLINE buf_page_t* buf_page_alloc_descriptor ( void )

Allocates a buf_page_t descriptor. This function must succeed. In case of failure we assert in this function.

Returns: : the allocated descriptor.

UNIV_INLINE ibool buf_page_belongs_to_unzip_LRU ( const buf_page_t * bpage )

Determines if a block should be on unzip_LRU list.

Returns: TRUE if block belongs to unzip_LRU

Parameters

bpage in: pointer to control block

UNIV_INLINE ibool buf_page_can_relocate ( const buf_page_t * bpage )

Determine if a buffer block can be relocated in memory. The block can be dirty, but it must not be I/O-fixed or bufferfixed.

Parameters

bpage control block being relocated

UNIV_INLINE void buf_page_free_descriptor ( buf_page_t * bpage )

Free a buf_page_t descriptor.

Parameters

bpage in: bpage descriptor to free.

UNIV_INLINE buf_block_t* buf_page_get_block ( buf_page_t * bpage )

Gets the buf_block_t handle of a buffered file block if an uncompressed page frame exists, or NULL.

Returns: control block, or NULL

Parameters

bpage in: control block, or NULL

UNIV_INLINE buf_flush_t buf_page_get_flush_type ( const buf_page_t * bpage )

Get the flush type of a page.

Returns: flush type

Parameters

bpage in: buffer page

UNIV_INLINE ulint buf_page_get_freed_page_clock ( const buf_page_t * bpage )

Reads the freed_page_clock of a buffer block.

Returns: freed_page_clock

Parameters

bpage in: block

UNIV_INLINE enum buf_io_fix buf_page_get_io_fix ( const buf_page_t * bpage )

Gets the io_fix state of a block.

Returns: io_fix state

Parameters

bpage in: pointer to the control block

UNIV_INLINE ib_mutex_t* buf_page_get_mutex ( const buf_page_t * bpage )

Gets the mutex of a block.

Returns: pointer to mutex protecting bpage

Parameters

bpage in: pointer to control block

UNIV_INLINE lsn_t buf_page_get_newest_modification ( const buf_page_t * bpage )

Gets the youngest modification log sequence number for a frame. Returns zero if not file page or no modification occurred yet.

Returns: newest modification to page

Parameters

bpage in: block containing the page frame

UNIV_INLINE ulint buf_page_get_page_no ( const buf_page_t * bpage )

Gets the page number of a block.

Returns: page number

Parameters

bpage in: pointer to the control block

UNIV_INLINE ulint buf_page_get_space ( const buf_page_t * bpage )

Gets the space id of a block.

Returns: space id

Parameters

bpage in: pointer to the control block

UNIV_INLINE enum buf_page_state buf_page_get_state ( const buf_page_t * bpage )

Gets the state of a block.

Returns: state

Parameters

bpage in: pointer to the control block

UNIV_INLINE ulint buf_page_get_zip_size ( const buf_page_t * bpage )

Gets the compressed page size of a block.

Returns: compressed page size, or 0

Parameters

bpage in: pointer to the control block

UNIV_INLINE buf_page_t* buf_page_hash_get_locked	(	buf_pool_t *	buf_pool,
		ulint	space,
		ulint	offset,
		rw_lock_t **	lock,
		ulint	lock_mode,
		bool	watch
	)

Returns the control block of a file page, NULL if not found. If the block is found and lock is not NULL then the appropriate page_hash lock is acquired in the specified lock mode. Otherwise, mode value is ignored. It is up to the caller to release the lock. If the block is found and the lock is NULL then the page_hash lock is released by this function.

Returns: block, NULL if not found, or watch sentinel (if watch is true)

Parameters

buf_pool	out: pointer to the bpage, or NULL; if NULL, hash_lock is also NULL. buffer pool instance
space	in: space id
offset	in: page number
lock	in/out: lock of the page hash acquired if bpage is found. NULL otherwise. If NULL is passed then the hash_lock is released by this function
lock_mode	in: RW_LOCK_EX or RW_LOCK_SHARED. Ignored if lock == NULL
watch	in: if true, return watch sentinel also.

UNIV_INLINE buf_page_t* buf_page_hash_get_low	(	buf_pool_t *	buf_pool,
		ulint	space,
		ulint	offset,
		ulint	fold
	)

Returns the control block of a file page, NULL if not found.

Returns: block, NULL if not found

Parameters

buf_pool	buffer pool instance
space	in: space id
offset	in: offset of the page within space
fold	in: buf_page_address_fold(space, offset)

UNIV_INLINE ibool buf_page_in_file ( const buf_page_t * bpage )

Determines if a block is mapped to a tablespace.

Returns: TRUE if mapped

Parameters

bpage in: pointer to control block

UNIV_INLINE unsigned buf_page_is_accessed ( const buf_page_t * bpage )

Determine the time of first access of a block in the buffer pool.

Returns: ut_time_ms() at the time of first access, 0 if not accessed

Parameters

bpage in: control block

UNIV_INLINE ibool buf_page_is_old ( const buf_page_t * bpage )

Determine if a block has been flagged old.

Returns: TRUE if old

Parameters

bpage in: control block

UNIV_INLINE ibool buf_page_peek	(	ulint	space,
		ulint	offset
	)

Returns TRUE if the page can be found in the buffer pool hash table.

NOTE that it is possible that the page is not yet read from disk, though.

Returns: TRUE if found in the page hash table

Parameters

space	in: space id
offset	in: page number

UNIV_INLINE ibool buf_page_peek_if_too_old ( const buf_page_t * bpage )

Recommends a move of a block to the start of the LRU list if there is danger of dropping from the buffer pool. NOTE: does not reserve the buffer pool mutex.

Returns: TRUE if should be made younger

Parameters

bpage in: block to make younger

UNIV_INLINE ibool buf_page_peek_if_young ( const buf_page_t * bpage )

Tells if a block is still close enough to the MRU end of the LRU list meaning that it is not in danger of getting evicted and also implying that it has been accessed recently. Note that this is for heuristics only and does not reserve buffer pool mutex.

Returns: TRUE if block is close to MRU end of LRU

Parameters

bpage in: block

UNIV_INLINE void buf_page_release	(	buf_block_t *	block,
		ulint	rw_latch
	)

Decrements the bufferfix count of a buffer control block and releases a latch, if specified.

Parameters

block	in: buffer block
rw_latch	in: RW_S_LATCH, RW_X_LATCH, RW_NO_LATCH

UNIV_INLINE void buf_page_release_zip ( buf_page_t * bpage )

Releases a compressed-only page acquired with buf_page_get_zip().

Parameters

bpage in: buffer block

UNIV_INLINE void buf_page_set_accessed ( buf_page_t * bpage )

Flag a block accessed.

Parameters

bpage in/out: control block

UNIV_INLINE void buf_page_set_flush_type	(	buf_page_t *	bpage,
		buf_flush_t	flush_type
	)

Set the flush type of a page.

Parameters

bpage	in: buffer page
flush_type	in: flush type

UNIV_INLINE void buf_page_set_io_fix	(	buf_page_t *	bpage,
		enum buf_io_fix	io_fix
	)

Sets the io_fix state of a block.

Parameters

bpage	in/out: control block
io_fix	in: io_fix state

UNIV_INLINE void buf_page_set_old	(	buf_page_t *	bpage,
		ibool	old
	)

Flag a block old.

Parameters

bpage	in/out: control block
old	in: old

UNIV_INLINE void buf_page_set_state	(	buf_page_t *	bpage,
		enum buf_page_state	state
	)

Sets the state of a block.

Parameters

bpage	in/out: pointer to control block
state	in: state

UNIV_INLINE void buf_page_set_sticky ( buf_page_t * bpage )

Makes a block sticky. A sticky block implies that even after we release the buf_pool->mutex and the block->mutex: it cannot be removed from the flush_list the block descriptor cannot be relocated it cannot be removed from the LRU list Note that: the block can still change its position in the LRU list the next and previous pointers can change.

Parameters

bpage in/out: control block

UNIV_INLINE void buf_page_unset_sticky ( buf_page_t * bpage )

Removes stickiness of a block.

Parameters

bpage in/out: control block

UNIV_INLINE buf_pool_t* buf_pool_from_array ( ulint index )

Returns the buffer pool instance given its array index

Returns: buffer pool

Parameters

index in: array index to get buffer pool instance from

UNIV_INLINE buf_pool_t* buf_pool_from_block ( const buf_block_t * block )

Returns the buffer pool instance given a block instance

Returns: buf_pool

Parameters

block in: block

UNIV_INLINE buf_pool_t* buf_pool_from_bpage ( const buf_page_t * bpage )

Returns the buffer pool instance given a page instance

Returns: buf_pool

Parameters

bpage in: buffer pool page

UNIV_INLINE buf_pool_t* buf_pool_get	(	ulint	space,
		ulint	offset
	)

Returns the buffer pool instance given space and offset of page

Returns: buffer pool

Parameters

space	in: space id
offset	in: offset of the page within space

UNIV_INLINE ulint buf_pool_get_curr_size ( void )

Gets the current size of buffer buf_pool in bytes.

Returns: size in bytes

UNIV_INLINE ulint buf_pool_get_n_pages ( void )

Gets the current size of buffer buf_pool in pages.

Returns: size in pages

UNIV_INLINE ulint buf_pool_index ( const buf_pool_t * buf_pool )

Calculates the index of a buffer pool to the buf_pool[] array.

Returns: the position of the buffer pool in buf_pool[]

Parameters

buf_pool in: buffer pool

UNIV_INLINE void buf_pool_mutex_enter_all ( void )

Acquire mutex on all buffer pool instances.

UNIV_INLINE void buf_pool_mutex_exit_all ( void )

Release mutex on all buffer pool instances.

UNIV_INLINE void buf_ptr_get_fsp_addr	(	const void *	ptr,
		ulint *	space,
		fil_addr_t *	addr
	)

Gets the space id, page offset, and byte offset within page of a pointer pointing to a buffer frame containing a file page.

Parameters

ptr	in: pointer to a buffer frame
space	out: space id
addr	out: page offset and byte offset

Data Structures

Functions

Detailed Description

Function Documentation