#include "univ.i"
#include "fil0fil.h"
#include "mtr0types.h"
#include "buf0types.h"
#include "hash0hash.h"
#include "ut0byte.h"
#include "page0types.h"
#include "ut0rbt.h"
#include "os0proc.h"
#include "log0log.h"
#include "buf0buf.ic"

Include dependency graph for buf0buf.h:

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

Go to the source code of this file.

Data Structures
struct	buf_pool_info_t
struct	buf_pools_list_size_t
struct	buf_page_t
struct	buf_block_t
struct	buf_buddy_free_t
struct	buf_pool_stat_t
	The buffer pool statistics structure. More...
struct	buf_buddy_stat_t
struct	buf_pool_t
	The buffer pool structure. More...
struct	CheckInLRUList
struct	CheckInFreeList
struct	CheckUnzipLRUAndLRUList

Macros
#define	MAX_BUFFER_POOLS_BITS 6
#define	MAX_BUFFER_POOLS (1 << MAX_BUFFER_POOLS_BITS)
#define	BUF_POOL_WATCH_SIZE (srv_n_purge_threads + 1)
#define	MAX_PAGE_HASH_LOCKS 1024
#define	BUF_NO_CHECKSUM_MAGIC 0xDEADBEEFUL
#define	buf_page_get(SP, ZS, OF, LA, MTR)
#define	buf_page_get_with_no_latch(SP, ZS, OF, MTR)
#define	buf_page_try_get(space_id, page_no, mtr) buf_page_try_get_func(space_id, page_no, __FILE__, __LINE__, mtr);
#define	buf_block_buf_fix_inc(b, f, l) buf_block_buf_fix_inc_func(f,l,b)
#define	buf_block_get_page_zip(block) ((block)->page.zip.data ? &(block)->page.zip : NULL)
#define	buf_pool_is_block_mutex(m) buf_pointer_is_block_field((const void*)(m))
#define	buf_pool_is_block_lock(l) buf_pointer_is_block_field((const void*)(l))
#define	buf_page_hash_get_s_locked(b, s, o, l) buf_page_hash_get_locked(b, s, o, l, RW_LOCK_SHARED)
#define	buf_page_hash_get_x_locked(b, s, o, l) buf_page_hash_get_locked(b, s, o, l, RW_LOCK_EX)
#define	buf_page_hash_get(b, s, o) buf_page_hash_get_locked(b, s, o, NULL, 0)
#define	buf_page_get_also_watch(b, s, o) buf_page_hash_get_locked(b, s, o, NULL, 0, true)
#define	buf_block_hash_get_s_locked(b, s, o, l) buf_block_hash_get_locked(b, s, o, l, RW_LOCK_SHARED)
#define	buf_block_hash_get_x_locked(b, s, o, l) buf_block_hash_get_locked(b, s, o, l, RW_LOCK_EX)
#define	buf_block_hash_get(b, s, o) buf_block_hash_get_locked(b, s, o, NULL, 0)
#define	BUF_PAGE_STATE_BITS 3
#define	buf_block_state_valid(block)
Modes for buf_page_get_gen
#define	BUF_GET 10
#define	BUF_GET_IF_IN_POOL 11
#define	BUF_PEEK_IF_IN_POOL 12
#define	BUF_GET_NO_LATCH 14
#define	BUF_GET_IF_IN_POOL_OR_WATCH 15
#define	BUF_GET_POSSIBLY_FREED 16
Modes for buf_page_get_known_nowait
#define	BUF_MAKE_YOUNG 51
#define	BUF_KEEP_OLD 52

#define	BUF_POOL_ZIP_FOLD_PTR(ptr) ((ulint) (ptr) / UNIV_PAGE_SIZE)
#define	BUF_POOL_ZIP_FOLD(b) BUF_POOL_ZIP_FOLD_PTR((b)->frame)
#define	BUF_POOL_ZIP_FOLD_BPAGE(b) BUF_POOL_ZIP_FOLD((buf_block_t*) (b))
Accessors for buf_pool->mutex.
Use these instead of accessing buf_pool->mutex directly.
#define	buf_pool_mutex_own(b) mutex_own(&b->mutex)
#define	buf_pool_mutex_enter(b)
#define	buf_flush_list_mutex_own(b) mutex_own(&b->flush_list_mutex)
#define	buf_flush_list_mutex_enter(b)
#define	buf_flush_list_mutex_exit(b)
#define	buf_block_mutex_own(b) mutex_own(&(b)->mutex)
#define	buf_block_mutex_enter(b)
#define	buf_block_mutex_exit(b)
#define	buf_page_hash_lock_get(b, f) hash_get_lock(b->page_hash, f)
#define	buf_page_hash_lock_held_s(b, p)
#define	buf_page_hash_lock_held_x(b, p)
#define	buf_page_hash_lock_held_s_or_x(b, p)
#define	buf_block_hash_lock_held_s(b, p) buf_page_hash_lock_held_s(b, &(p->page))
#define	buf_block_hash_lock_held_x(b, p) buf_page_hash_lock_held_x(b, &(p->page))
#define	buf_block_hash_lock_held_s_or_x(b, p) buf_page_hash_lock_held_s_or_x(b, &(p->page))
#define	buf_pool_mutex_exit_forbid(b)
#define	buf_pool_mutex_exit_allow(b)
#define	buf_pool_mutex_exit(b)

Enumerations
enum	buf_page_state { BUF_BLOCK_POOL_WATCH, BUF_BLOCK_ZIP_PAGE, BUF_BLOCK_ZIP_DIRTY, BUF_BLOCK_NOT_USED, BUF_BLOCK_READY_FOR_USE, BUF_BLOCK_FILE_PAGE, BUF_BLOCK_MEMORY, BUF_BLOCK_REMOVE_HASH }
	States of a control block. More...
enum	buf_page_print_flags { BUF_PAGE_PRINT_NO_CRASH = 1, BUF_PAGE_PRINT_NO_FULL = 2 }

Functions
UNIV_INLINE void	buf_pool_mutex_enter_all (void)
UNIV_INLINE void	buf_pool_mutex_exit_all (void)
UNIV_INTERN dberr_t	buf_pool_init (ulint size, ulint n_instances)
UNIV_INTERN void	buf_pool_free (ulint n_instances)
UNIV_INTERN void	buf_pool_clear_hash_index (void)
UNIV_INTERN void	buf_relocate (buf_page_t bpage, buf_page_t dpage))
UNIV_INLINE ulint	buf_pool_get_curr_size (void)
UNIV_INLINE ulint	buf_pool_get_n_pages (void)
UNIV_INTERN lsn_t	buf_pool_get_oldest_modification (void)
UNIV_INLINE buf_page_t *	buf_page_alloc_descriptor (void))
UNIV_INLINE void	buf_page_free_descriptor (buf_page_t *bpage))
UNIV_INTERN buf_block_t *	buf_block_alloc (buf_pool_t *buf_pool)
UNIV_INLINE void	buf_block_free (buf_block_t *block)
UNIV_INLINE byte *	buf_frame_copy (byte buf, const buf_frame_t frame)
UNIV_INTERN ibool	buf_page_optimistic_get (ulint rw_latch, buf_block_t block, ib_uint64_t modify_clock, const char file, ulint line, mtr_t *mtr)
UNIV_INTERN ibool	buf_page_get_known_nowait (ulint rw_latch, buf_block_t block, ulint mode, const char file, ulint line, mtr_t *mtr)
UNIV_INTERN const buf_block_t *	buf_page_try_get_func (ulint space_id, ulint page_no, const char file, ulint line, mtr_t mtr)
UNIV_INTERN buf_page_t *	buf_page_get_zip (ulint space, ulint zip_size, ulint offset)
UNIV_INTERN buf_block_t *	buf_page_get_gen (ulint space, ulint zip_size, ulint offset, ulint rw_latch, buf_block_t guess, ulint mode, const char file, ulint line, mtr_t *mtr)
UNIV_INTERN buf_block_t *	buf_page_create (ulint space, ulint offset, ulint zip_size, mtr_t *mtr)
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_INTERN void	buf_page_make_young (buf_page_t *bpage)
UNIV_INLINE ibool	buf_page_peek (ulint space, ulint offset)
UNIV_INTERN buf_page_t *	buf_page_set_file_page_was_freed (ulint space, ulint offset)
UNIV_INTERN buf_page_t *	buf_page_reset_file_page_was_freed (ulint space, ulint offset)
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 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_buf_fix_inc_func (const char file, ulint line, buf_block_t block))
UNIV_INLINE void	buf_block_fix (buf_block_t *block)
UNIV_INLINE void	buf_block_unfix (buf_block_t *block)
UNIV_INTERN ibool	buf_page_is_corrupted (bool check_lsn, const byte *read_buf, ulint zip_size))
bool	buf_page_is_zeroes (const byte *read_buf, const ulint zip_size)
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_INTERN buf_block_t *	buf_pool_contains_zip (buf_pool_t buf_pool, const void data)
UNIV_INLINE buf_frame_t *	buf_frame_align (byte *ptr)
UNIV_INTERN ibool	buf_validate (void)
UNIV_INTERN void	buf_print (void)
UNIV_INTERN void	buf_page_print (const byte *read_buf, ulint zip_size, ulint flags) UNIV_COLD)
UNIV_INTERN ibool	buf_zip_decompress (buf_block_t *block, ibool check)
UNIV_INTERN ulint	buf_get_latched_pages_number (void)
UNIV_INTERN ulint	buf_get_n_pending_read_ios (void)
UNIV_INTERN void	buf_print_io (FILE *file)
UNIV_INTERN void	buf_stats_get_pool_info (buf_pool_t buf_pool, ulint pool_id, buf_pool_info_t all_pool_info)
UNIV_INTERN ulint	buf_get_modified_ratio_pct (void)
UNIV_INTERN void	buf_refresh_io_stats (buf_pool_t *buf_pool)
UNIV_INTERN void	buf_refresh_io_stats_all (void)
UNIV_INTERN ibool	buf_all_freed (void)
UNIV_INTERN ulint	buf_pool_check_no_pending_io (void)
UNIV_INTERN void	buf_pool_invalidate (void)
UNIV_INLINE void	buf_block_dbg_add_level (buf_block_t *block, ulint level)
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 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_INTERN buf_block_t *	buf_block_align (const byte *ptr)
UNIV_INTERN ibool	buf_pointer_is_block_field (const void *ptr)
UNIV_INLINE const page_zip_des_t *	buf_frame_get_page_zip (const byte *ptr)
UNIV_INTERN buf_page_t *	buf_page_init_for_read (dberr_t *err, ulint mode, ulint space, ulint zip_size, ibool unzip, ib_int64_t tablespace_version, ulint offset)
UNIV_INTERN bool	buf_page_io_complete (buf_page_t *bpage)
UNIV_INLINE ulint	buf_page_address_fold (ulint space, ulint offset))
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 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=false)
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_INTERN ulint	buf_get_free_list_len (void)
UNIV_INTERN ibool	buf_pool_watch_is_sentinel (buf_pool_t buf_pool, const buf_page_t bpage))
UNIV_INTERN buf_page_t *	buf_pool_watch_set (ulint space, ulint offset, ulint fold))
UNIV_INTERN void	buf_pool_watch_unset (ulint space, ulint offset)
UNIV_INTERN ibool	buf_pool_watch_occurred (ulint space, ulint offset))
UNIV_INTERN void	buf_get_total_list_len (ulint LRU_len, ulint free_len, ulint *flush_list_len)
UNIV_INTERN void	buf_get_total_list_size_in_bytes (buf_pools_list_size_t *buf_pools_list_size)
UNIV_INTERN void	buf_get_total_stat (buf_pool_stat_t *tot_stat)
UNIV_INLINE buf_block_t *	buf_get_nth_chunk_block (const buf_pool_t buf_pool, ulint n, ulint chunk_size)
UNIV_INTERN void	buf_flush_update_zip_checksum (buf_frame_t *page, ulint zip_size, lsn_t lsn)

Variables
buf_pool_t *	buf_pool_ptr
ibool	buf_debug_prints
ulint	srv_buf_pool_instances
ulint	srv_buf_pool_curr_size

Detailed Description

The database buffer pool high-level routines

Created 11/5/1995 Heikki Tuuri

Macro Definition Documentation

#define buf_block_buf_fix_inc	(	b,
		f,
		l
	)	buf_block_buf_fix_inc_func(f,l,b)

Increments the bufferfix count.

Parameters

b	in/out: block to bufferfix
f	in: file name where requested
l	in: line number where requested

#define buf_block_get_page_zip ( block ) ((block)->page.zip.data ? &(block)->page.zip : NULL)

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

#define buf_block_mutex_enter ( b )

Value:

do {                    \
        mutex_enter(&(b)->mutex);                       \
} while (0)

Acquire the block->mutex.

#define buf_block_mutex_exit ( b )

Value:

do {                    \
        mutex_exit(&(b)->mutex);                                \
} while (0)

Release the trx->mutex.

#define buf_block_mutex_own ( b ) mutex_own(&(b)->mutex)

Test if block->mutex is owned.

#define buf_block_state_valid ( block )

Value:

(buf_block_get_state(block) >= BUF_BLOCK_NOT_USED \

&& (buf_block_get_state(block) <= BUF_BLOCK_REMOVE_HASH))

Check if a buf_block_t object is in a valid state

Parameters

block buffer block

Returns: TRUE if valid

#define buf_flush_list_mutex_enter ( b )

Value:

do {            \
        mutex_enter(&b->flush_list_mutex);              \
} while (0)

Acquire the flush list mutex.

#define buf_flush_list_mutex_exit ( b )

Value:

do {            \
        mutex_exit(&b->flush_list_mutex);               \
} while (0)

Release the flush list mutex.

#define buf_flush_list_mutex_own ( b ) mutex_own(&b->flush_list_mutex)

Test if flush list mutex is owned.

#define BUF_GET 10

get always

#define BUF_GET_IF_IN_POOL 11

get if in pool

#define BUF_GET_IF_IN_POOL_OR_WATCH 15

Get the page only if it's in the buffer pool, if not then set a watch on the page.

#define BUF_GET_NO_LATCH 14

get and bufferfix, but set no latch; we have separated this case, because it is error-prone programming not to set a latch, and it should be used with care

#define BUF_GET_POSSIBLY_FREED 16

Like BUF_GET, but do not mind if the file page has been freed.

#define BUF_KEEP_OLD 52

Preserve the current LRU position of the block.

#define BUF_MAKE_YOUNG 51

Move the block to the start of the LRU list if there is a danger that the block would drift out of the buffer pool

#define BUF_NO_CHECKSUM_MAGIC 0xDEADBEEFUL

Magic value to use instead of checksums when they are disabled

#define buf_page_get	(	SP,
		ZS,
		OF,
		LA,
		MTR
	)

Value:

buf_page_get_gen(\
                                SP, ZS, OF, LA, NULL,\
                                BUF_GET, __FILE__, __LINE__, MTR)

NOTE! The following macros should be used instead of buf_page_get_gen, to improve debugging. Only values RW_S_LATCH and RW_X_LATCH are allowed in LA!

#define buf_page_get_with_no_latch	(	SP,
		ZS,
		OF,
		MTR
	)

Value:

buf_page_get_gen(\
                                SP, ZS, OF, RW_NO_LATCH, NULL,\
                                BUF_GET_NO_LATCH, __FILE__, __LINE__, MTR)

Use these macros to bufferfix a page with no latching. Remember not to read the contents of the page unless you know it is safe. Do not modify the contents of the page! We have separated this case, because it is error-prone programming not to set a latch, and it should be used with care.

#define buf_page_hash_lock_get	(	b,
		f
	)	hash_get_lock(b->page_hash, f)

Get appropriate page_hash_lock.

#define buf_page_hash_lock_held_s	(	b,
		p
	)

Value:

rw_lock_own(buf_page_hash_lock_get(b,           \
                  buf_page_address_fold(p->space,       \
                                        p->offset)),    \
                                        RW_LOCK_SHARED)

Test if page_hash lock is held in s-mode.

#define buf_page_hash_lock_held_s_or_x	(	b,
		p
	)

Value:

(buf_page_hash_lock_held_s(b, p) \

|| buf_page_hash_lock_held_x(b, p))

Test if page_hash lock is held in x or s-mode.

#define buf_page_hash_lock_held_x	(	b,
		p
	)

Value:

rw_lock_own(buf_page_hash_lock_get(b,           \
                  buf_page_address_fold(p->space,       \
                                        p->offset)),    \
                                        RW_LOCK_EX)

Test if page_hash lock is held in x-mode.

#define BUF_PAGE_STATE_BITS 3

The common buffer control block structure

for compressed and uncompressed frames Number of bits used for buffer page states.

#define buf_page_try_get	(	space_id,
		page_no,
		mtr
	)	buf_page_try_get_func(space_id, page_no, __FILE__, __LINE__, mtr);

Tries to get a page. If the page is not in the buffer pool it is

not loaded. Suitable for using when holding the lock_sys_t::mutex.

Parameters

space_id	in: tablespace id
page_no	in: page number
mtr	in: mini-transaction

Returns: the page if in buffer pool, NULL if not

#define BUF_PEEK_IF_IN_POOL 12

get if in pool, do not make the block young in the LRU list

#define buf_pool_is_block_lock ( l ) buf_pointer_is_block_field((const void*)(l))

Find out if a pointer corresponds to a buf_block_t::lock.

Parameters

l	in: rw-lock candidate

Returns: TRUE if l is a buf_block_t::lock

#define buf_pool_is_block_mutex ( m ) buf_pointer_is_block_field((const void*)(m))

Find out if a pointer corresponds to a buf_block_t::mutex.

Parameters

m	in: mutex candidate

Returns: TRUE if m is a buf_block_t::mutex

#define buf_pool_mutex_enter ( b )

Value:

do {                    \
        ut_ad(!mutex_own(&b->zip_mutex));               \
        mutex_enter(&b->mutex);                         \
} while (0)

Acquire a buffer pool mutex.

#define buf_pool_mutex_exit ( b )

Value:

do {            \
        ut_a(!b->mutex_exit_forbidden);         \
        mutex_exit(&b->mutex);                  \
} while (0)

Release the buffer pool mutex.

#define buf_pool_mutex_exit_allow ( b )

Value:

do {    \
        ut_ad(buf_pool_mutex_own(b));           \
        ut_a(b->mutex_exit_forbidden);  \
        b->mutex_exit_forbidden--;              \
} while (0)

Allow the release of the buffer pool mutex.

#define buf_pool_mutex_exit_forbid ( b )

Value:

do {    \
        ut_ad(buf_pool_mutex_own(b));           \
        b->mutex_exit_forbidden++;              \
} while (0)

Forbid the release of the buffer pool mutex.

#define buf_pool_mutex_own ( b ) mutex_own(&b->mutex)

Test if a buffer pool mutex is owned.

#define BUF_POOL_WATCH_SIZE (srv_n_purge_threads + 1)

Maximum number of concurrent buffer pool watches

#define BUF_POOL_ZIP_FOLD_PTR ( ptr ) ((ulint) (ptr) / UNIV_PAGE_SIZE)

Compute the hash fold value for blocks in buf_pool->zip_hash.

#define MAX_BUFFER_POOLS (1 << MAX_BUFFER_POOLS_BITS)

The maximum number of buffer pools that can be defined

#define MAX_BUFFER_POOLS_BITS 6

Number of bits to representing a buffer pool ID

#define MAX_PAGE_HASH_LOCKS 1024

The maximum number of page_hash locks

Enumeration Type Documentation

enum buf_page_print_flags

Enumerator:

BUF_PAGE_PRINT_NO_CRASH	Do not crash at the end of buf_page_print().
BUF_PAGE_PRINT_NO_FULL	Do not print the full page dump.

enum buf_page_state

States of a control block.

See Also: buf_page_t

The enumeration values must be 0..7.

Enumerator:

BUF_BLOCK_POOL_WATCH	a sentinel for the buffer pool watch, element of buf_pool->watch[]
BUF_BLOCK_ZIP_PAGE	contains a clean compressed page
BUF_BLOCK_ZIP_DIRTY	contains a compressed page that is in the buf_pool->flush_list
BUF_BLOCK_NOT_USED	is in the free list; must be after the BUF_BLOCK_ZIP_ constants for compressed-only pages See Also buf_block_state_valid()
BUF_BLOCK_READY_FOR_USE	when buf_LRU_get_free_block returns a block, it is in this state
BUF_BLOCK_FILE_PAGE	contains a buffered file page
BUF_BLOCK_MEMORY	contains some main memory object
BUF_BLOCK_REMOVE_HASH	hash index should be removed before putting to the free list

Function Documentation

UNIV_INTERN ibool buf_all_freed ( void )

Asserts that all file pages in the buffer are in a replaceable state.

Returns: TRUE

UNIV_INTERN buf_block_t* buf_block_align ( const byte * ptr )

Gets the block to whose frame the pointer is pointing to.

Returns: pointer to block, never NULL in: pointer to a frame

UNIV_INTERN buf_block_t* buf_block_alloc ( buf_pool_t * buf_pool )

Allocates a buffer block.

Returns: own: the allocated block, in state BUF_BLOCK_MEMORY in: buffer pool instance, or NULL for round-robin selection of the buffer pool

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. in: latching order 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. in/out: block to bufferfix

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. in, own: block to be freed

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 a block. This can be used in searches in the lock hash table.

Returns: lock hash value

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 in: 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 in: RW_LOCK_EX or RW_LOCK_SHARED. Ignored if lock == NULL

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. in: 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. in: page number

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. in: io_fix state

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. in: 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 )

Increments the bufferfix count. in/out: block to bufferfix

Decrements the bufferfix count.

Parameters

block in/out: block to bufferunfix

UNIV_INTERN void buf_flush_update_zip_checksum	(	buf_frame_t *	page,
		ulint	zip_size,
		lsn_t	lsn
	)

Calculate the checksum of a page from compressed table and update the page. in: Lsn to stamp on the page

Parameters

page	in/out: Page to update
zip_size	in: Compressed page size

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 in: buffer 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 in: pointer to the page

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_INTERN ulint buf_get_free_list_len ( void )

Gets the current length of the free list of buffer blocks.

Returns: length of the free list

UNIV_INTERN ulint buf_get_latched_pages_number ( void )

Returns the number of latched pages in the buffer pool.

Returns: number of latched pages

UNIV_INTERN ulint buf_get_modified_ratio_pct ( void )

Returns the ratio in percents of modified pages in the buffer pool / database pages in the buffer pool.

Returns: modified page percentage ratio

UNIV_INTERN ulint buf_get_n_pending_read_ios ( void )

Returns the number of pending buf pool read ios.

Returns: number of pending read I/O operations

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. in: 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_INTERN void buf_get_total_list_len	(	ulint *	LRU_len,
		ulint *	free_len,
		ulint *	flush_list_len
	)

Get total buffer pool statistics. out: length of all flush lists

Parameters

LRU_len	out: length of all LRU lists
free_len	out: length of all free lists

UNIV_INTERN void buf_get_total_list_size_in_bytes ( buf_pools_list_size_t * buf_pools_list_size )

Get total list size in bytes from all buffer pools. out: list sizes in all buffer pools

UNIV_INTERN void buf_get_total_stat ( buf_pool_stat_t * tot_stat )

Get total buffer pool statistics. out: buffer pool stats

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_INTERN buf_block_t* buf_page_create	(	ulint	space,
		ulint	offset,
		ulint	zip_size,
		mtr_t *	mtr
	)

Initializes a page to the buffer buf_pool. The page is usually not read from a file even if it cannot be found in the buffer buf_pool. This is one of the functions which perform to a block a state transition NOT_USED => FILE_PAGE (the other is buf_page_get_gen).

Returns: pointer to the block, page bufferfixed in: mini-transaction handle

Parameters

space	in: space id
offset	in: offset of the page within space in units of a page
zip_size	in: compressed page size, or 0

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. Note: even though bpage is not declared a const we don't update its value. It is safe to make this pure.

Returns: control block, or NULL

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_INTERN buf_block_t* buf_page_get_gen	(	ulint	space,
		ulint	zip_size,
		ulint	offset,
		ulint	rw_latch,
		buf_block_t *	guess,
		ulint	mode,
		const char *	file,
		ulint	line,
		mtr_t *	mtr
	)

This is the general function used to get access to a database page.

Returns: pointer to the block or NULL in: mini-transaction

Parameters

space	in: space id
zip_size	in: compressed page size in bytes or 0 for uncompressed pages
offset	in: page number
rw_latch	in: RW_S_LATCH, RW_X_LATCH, RW_NO_LATCH
guess	in: guessed block or NULL
mode	in: BUF_GET, BUF_GET_IF_IN_POOL, BUF_PEEK_IF_IN_POOL, BUF_GET_NO_LATCH or BUF_GET_IF_IN_POOL_OR_WATCH
file	in: file name
line	in: line where called

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_INTERN ibool buf_page_get_known_nowait	(	ulint	rw_latch,
		buf_block_t *	block,
		ulint	mode,
		const char *	file,
		ulint	line,
		mtr_t *	mtr
	)

This is used to get access to a known database page, when no waiting can be done.

Returns: TRUE if success in: mini-transaction

Parameters

rw_latch	in: RW_S_LATCH, RW_X_LATCH
block	in: the known page
mode	in: BUF_MAKE_YOUNG or BUF_KEEP_OLD
file	in: file name
line	in: line where called

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 in: block containing the page frame

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 in: pointer to the control block

Gets the state of a block.

Returns: state

Parameters

bpage in: pointer to the control block

UNIV_INTERN buf_page_t* buf_page_get_zip	(	ulint	space,
		ulint	zip_size,
		ulint	offset
	)

Get read access to a compressed page (usually of type FIL_PAGE_TYPE_ZBLOB or FIL_PAGE_TYPE_ZBLOB2). The page must be released with buf_page_release_zip(). NOTE: the page is not protected by any latch. Mutual exclusion has to be implemented at a higher level. In other words, all possible accesses to a given page through this function must be protected by the same set of mutexes or latches.

Returns: pointer to the block, or NULL if not compressed in: page number

Parameters

space	in: space id
zip_size	in: compressed page size

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) in: if true, return watch sentinel also.

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 in: buf_page_address_fold(space, offset)

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_INTERN buf_page_t* buf_page_init_for_read	(	dberr_t *	err,
		ulint	mode,
		ulint	space,
		ulint	zip_size,
		ibool	unzip,
		ib_int64_t	tablespace_version,
		ulint	offset
	)

Function which inits a page for read to the buffer buf_pool. If the page is (1) already in buf_pool, or (2) if we specify to read only ibuf pages and the page is not an ibuf page, or (3) if the space is deleted or being deleted, then this function does nothing. Sets the io_fix flag to BUF_IO_READ and sets a non-recursive exclusive lock on the buffer frame. The io-handler must take care that the flag is cleared and the lock released later.

Returns: pointer to the block or NULL in: page number

Parameters

err	out: DB_SUCCESS or DB_TABLESPACE_DELETED
mode	in: BUF_READ_IBUF_PAGES_ONLY, ...
space	in: space id
zip_size	in: compressed page size, or 0
unzip	in: TRUE=request uncompressed page
tablespace_version	in: prevents reading from a wrong version of the tablespace in case we have done DISCARD + IMPORT

UNIV_INTERN bool buf_page_io_complete ( buf_page_t * bpage )

Completes an asynchronous read or write request of a file page to or from the buffer pool.

Returns: true if successful in: pointer to the block in question

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_INTERN ibool buf_page_is_corrupted	(	bool	check_lsn,
		const byte *	read_buf,
		ulint	zip_size
	)

Checks if a page is corrupt.

Returns: TRUE if corrupted

Parameters

check_lsn	in: true if we need to check the and complain about the LSN
read_buf	in: a database page
zip_size	in: size of compressed page; 0 for uncompressed pages

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

bool buf_page_is_zeroes	(	const byte *	read_buf,
		const ulint	zip_size
	)

Checks if a page is all zeroes.

Returns: TRUE if the page is all zeroes in: size of compressed page; 0 for uncompressed pages

Parameters

read_buf in: a database page

UNIV_INTERN void buf_page_make_young ( buf_page_t * bpage )

Moves a page to the start of the buffer pool LRU list. This high-level function can be used to prevent an important page from slipping out of the buffer pool. in: buffer block of a file page

UNIV_INTERN ibool buf_page_optimistic_get	(	ulint	rw_latch,
		buf_block_t *	block,
		ib_uint64_t	modify_clock,
		const char *	file,
		ulint	line,
		mtr_t *	mtr
	)

This is the general function used to get optimistic access to a database page.

Returns: TRUE if success in: mini-transaction

Parameters

rw_latch	in: RW_S_LATCH, RW_X_LATCH
block	in: guessed block
modify_clock	in: modify clock value
file	in: file name
line	in: line where called

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 in: page number

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 in: block to make younger

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 in: block

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_INTERN void buf_page_print	(	const byte *	read_buf,
		ulint	zip_size,
		ulint	flags
	)

Prints a page to stderr.

Parameters

read_buf	in: a database page
zip_size	in: compressed page size, or 0 for uncompressed pages
flags	in: 0 or BUF_PAGE_PRINT_NO_CRASH or BUF_PAGE_PRINT_NO_FULL

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. in: RW_S_LATCH, RW_X_LATCH, RW_NO_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(). in: buffer block

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

Parameters

bpage in: buffer block

UNIV_INTERN buf_page_t* buf_page_reset_file_page_was_freed	(	ulint	space,
		ulint	offset
	)

Sets file_page_was_freed FALSE if the page is found in the buffer pool. This function should be called when we free a file page and want the debug version to check that it is not accessed any more unless reallocated.

Returns: control block if found in page hash table, otherwise NULL in: page number

Parameters

space in: space id

UNIV_INLINE void buf_page_set_accessed ( buf_page_t * bpage )

Flag a block accessed.

Parameters

bpage in/out: control block

UNIV_INTERN buf_page_t* buf_page_set_file_page_was_freed	(	ulint	space,
		ulint	offset
	)

Sets file_page_was_freed TRUE if the page is found in the buffer pool. This function should be called when we free a file page and want the debug version to check that it is not accessed any more unless reallocated.

Returns: control block if found in page hash table, otherwise NULL in: page number

Parameters

space in: space id

UNIV_INLINE void buf_page_set_flush_type	(	buf_page_t *	bpage,
		buf_flush_t	flush_type
	)

Set the flush type of a page. in: 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. in: io_fix state

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. in: 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. in: 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. in/out: control block

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_INTERN const buf_block_t* buf_page_try_get_func	(	ulint	space_id,
		ulint	page_no,
		const char *	file,
		ulint	line,
		mtr_t *	mtr
	)

Given a tablespace id and page number tries to get that page. If the page is not in the buffer pool it is not loaded and NULL is returned. Suitable for using when holding the lock_sys_t::mutex. in: mini-transaction

Parameters

space_id	in: tablespace id
page_no	in: page number
file	in: file name
line	in: line where called

UNIV_INLINE void buf_page_unset_sticky ( buf_page_t * bpage )

Removes stickiness of a block. in/out: control block

Removes stickiness of a block.

Parameters

bpage in/out: control block

UNIV_INTERN ibool buf_pointer_is_block_field ( const void * ptr )

Find out if a pointer belongs to a buf_block_t. It can be a pointer to the buf_block_t itself or a member of it

Returns: TRUE if ptr belongs to a buf_block_t struct in: pointer not dereferenced

UNIV_INTERN ulint buf_pool_check_no_pending_io ( void )

Checks that there currently are no pending i/o-operations for the buffer pool.

Returns: number of pending i/o operations

UNIV_INTERN void buf_pool_clear_hash_index ( void )

Clears the adaptive hash index on all pages in the buffer pool.

UNIV_INTERN buf_block_t* buf_pool_contains_zip	(	buf_pool_t *	buf_pool,
		const void *	data
	)

Finds a block in the buffer pool that points to a given compressed page.

Returns: buffer block pointing to the compressed page, or NULL in: pointer to compressed page

Parameters

buf_pool in: buffer pool instance

UNIV_INTERN void buf_pool_free ( ulint n_instances )

Frees the buffer pool at shutdown. This must not be invoked before freeing all mutexes. in: numbere of instances to free

UNIV_INLINE buf_pool_t* buf_pool_from_array ( ulint index )

Returns the buffer pool instance given its array index

Returns: buffer pool in: array index to get buffer pool instance from

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 in: 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 in: buffer pool page

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 in: offset of the page within space

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 frames.

Returns: size in pages

Gets the current size of buffer buf_pool in pages.

Returns: size in pages

UNIV_INTERN lsn_t buf_pool_get_oldest_modification ( void )

Gets the smallest oldest_modification lsn for any page in the pool. Returns zero if all modified pages have been flushed to disk.

Returns: oldest modification in pool, zero if none

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_INTERN dberr_t buf_pool_init	(	ulint	size,
		ulint	n_instances
	)

Creates the buffer pool.

Returns: DB_SUCCESS if success, DB_ERROR if not enough memory or error in: Number of instances

Parameters

size	in: Size of the total pool in bytes

UNIV_INTERN void buf_pool_invalidate ( void )

Invalidates the file pages in the buffer pool when an archive recovery is completed. All the file pages buffered must be in a replaceable state when this function is called: not latched and not modified.

UNIV_INLINE void buf_pool_mutex_enter_all ( void )

Acquire mutex on all buffer pool instances

Acquire mutex on all buffer pool instances.

UNIV_INLINE void buf_pool_mutex_exit_all ( void )

Release mutex on all buffer pool instances

Release mutex on all buffer pool instances.

UNIV_INTERN ibool buf_pool_watch_is_sentinel	(	buf_pool_t *	buf_pool,
		const buf_page_t *	bpage
	)

Determine if a block is a sentinel for a buffer pool watch.

Returns: TRUE if a sentinel for a buffer pool watch, FALSE if not

Parameters

buf_pool	buffer pool instance
bpage	in: block

UNIV_INTERN ibool buf_pool_watch_occurred	(	ulint	space,
		ulint	offset
	)

Check if the page has been read in. This may only be called after buf_pool_watch_set(space,offset) has returned NULL and before invoking buf_pool_watch_unset(space,offset).

Returns: FALSE if the given page was not read in, TRUE if it was

Parameters

space	in: space id
offset	in: page number

UNIV_INTERN buf_page_t* buf_pool_watch_set	(	ulint	space,
		ulint	offset,
		ulint	fold
	)

Add watch for the given page to be read in. Caller must have the buffer pool

Returns: NULL if watch set, block if the page is in the buffer pool

Parameters

space	in: space id
offset	in: page number
fold	in: buf_page_address_fold(space, offset)

UNIV_INTERN void buf_pool_watch_unset	(	ulint	space,
		ulint	offset
	)

Stop watching if the page has been read in. buf_pool_watch_set(space,offset) must have returned NULL before. in: page number

Parameters

space in: space id

UNIV_INTERN void buf_print ( void )

Prints info of the buffer pool data structure.

UNIV_INTERN void buf_print_io ( FILE * file )

Prints info of the buffer i/o. in: file where to print

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. out: page offset and byte offset

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

UNIV_INTERN void buf_refresh_io_stats ( buf_pool_t * buf_pool )

Refreshes the statistics used to print per-second averages. buffer pool instance

UNIV_INTERN void buf_refresh_io_stats_all ( void )

Refreshes the statistics used to print per-second averages.

UNIV_INTERN void buf_relocate	(	buf_page_t *	bpage,
		buf_page_t *	dpage
	)

Relocate a buffer control block. Relocates the block on the LRU list and in buf_pool->page_hash. Does not relocate bpage->list. The caller must take care of relocating bpage->list.

Parameters

bpage	in/out: control block being relocated; buf_page_get_state(bpage) must be BUF_BLOCK_ZIP_DIRTY or BUF_BLOCK_ZIP_PAGE
dpage	in/out: destination control block

UNIV_INTERN void buf_stats_get_pool_info	(	buf_pool_t *	buf_pool,
		ulint	pool_id,
		buf_pool_info_t *	all_pool_info
	)

Collect buffer pool stats information for a buffer pool. Also record aggregated stats if there are more than one buffer pool in the server in/out: buffer pool info to fill

Parameters

buf_pool	in: buffer pool
pool_id	in: buffer pool ID

UNIV_INTERN ibool buf_validate ( void )

Validates the buffer pool data structure.

Returns: TRUE

UNIV_INTERN ibool buf_zip_decompress	(	buf_block_t *	block,
		ibool	check
	)

Decompress a block.

Returns: TRUE if successful in: TRUE=verify the page checksum

Parameters

block in/out: block

Variable Documentation

ibool buf_debug_prints

If this is set TRUE, the program prints info whenever read or flush occurs

buf_pool_t* buf_pool_ptr

The buffer pools of the database

Data Structures

Macros

Enumerations

Functions

Variables

Detailed Description

Macro Definition Documentation

Enumeration Type Documentation

Function Documentation

Variable Documentation