diff options
Diffstat (limited to 'storage/innobase/include/buf0buf.h')
| -rw-r--r-- | storage/innobase/include/buf0buf.h | 1366 |
1 files changed, 547 insertions, 819 deletions
diff --git a/storage/innobase/include/buf0buf.h b/storage/innobase/include/buf0buf.h index a84ea047a54..2b4732a64a0 100644 --- a/storage/innobase/include/buf0buf.h +++ b/storage/innobase/include/buf0buf.h @@ -24,40 +24,30 @@ The database buffer pool high-level routines Created 11/5/1995 Heikki Tuuri *******************************************************/ -#ifndef buf0buf_h -#define buf0buf_h +#pragma once /** Magic value to use instead of checksums when they are disabled */ #define BUF_NO_CHECKSUM_MAGIC 0xDEADBEEFUL #include "fil0fil.h" #include "mtr0types.h" -#include "buf0types.h" #include "span.h" #include "assume_aligned.h" +#include "buf0types.h" #ifndef UNIV_INNOCHECKSUM -#include "hash0hash.h" #include "ut0byte.h" #include "page0types.h" #include "log0log.h" #include "srv0srv.h" +#include "transactional_lock_guard.h" #include <ostream> -// Forward declaration -struct fil_addr_t; - /** @name Modes for buf_page_get_gen */ /* @{ */ #define BUF_GET 10 /*!< get always */ #define BUF_GET_IF_IN_POOL 11 /*!< get if in pool */ #define BUF_PEEK_IF_IN_POOL 12 /*!< get if in pool, do not make the block young in the LRU list */ -#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_IF_IN_POOL_OR_WATCH 15 /*!< Get the page only if it's in the buffer pool, if not then set a watch @@ -65,7 +55,6 @@ struct fil_addr_t; #define BUF_GET_POSSIBLY_FREED 16 /*!< Like BUF_GET, but do not mind if the file page has been freed. */ -#define BUF_EVICT_IF_IN_POOL 20 /*!< evict a clean block if found */ /* @} */ /** If LRU list of a buf_pool is less than this size then LRU eviction @@ -74,22 +63,6 @@ the blocks on free list. If LRU list is very small then we can end up in thrashing. */ #define BUF_LRU_MIN_LEN 256 -/** buf_page_t::state() values, distinguishing buf_page_t and buf_block_t */ -enum buf_page_state -{ - /** available in buf_pool.free or buf_pool.watch */ - BUF_BLOCK_NOT_USED, - /** allocated for something else than a file page */ - BUF_BLOCK_MEMORY, - /** a previously allocated file page, in transit to NOT_USED */ - BUF_BLOCK_REMOVE_HASH, - /** a buf_block_t that is also in buf_pool.LRU */ - BUF_BLOCK_FILE_PAGE, - /** the buf_page_t of a ROW_FORMAT=COMPRESSED page - whose uncompressed page frame has been evicted */ - BUF_BLOCK_ZIP_PAGE -}; - /** This structure defines information we will fetch from each buffer pool. It will be used to print table IO stats */ struct buf_pool_info_t @@ -170,33 +143,10 @@ operator<<( const page_id_t page_id); #ifndef UNIV_INNOCHECKSUM -/*********************************************************************//** -Gets the current size of buffer buf_pool in bytes. -@return size in bytes */ -UNIV_INLINE -ulint -buf_pool_get_curr_size(void); -/*========================*/ - -/********************************************************************//** -Allocates a buf_page_t descriptor. This function must succeed. In case -of failure we assert in this function. */ -UNIV_INLINE -buf_page_t* -buf_page_alloc_descriptor(void) -/*===========================*/ - MY_ATTRIBUTE((malloc)); -/********************************************************************//** -Free a buf_page_t descriptor. */ -UNIV_INLINE -void -buf_page_free_descriptor( -/*=====================*/ - buf_page_t* bpage) /*!< in: bpage descriptor to free. */ - MY_ATTRIBUTE((nonnull)); +# define buf_pool_get_curr_size() srv_buf_pool_curr_size /** Allocate a buffer block. -@return own: the allocated block, in state BUF_BLOCK_MEMORY */ +@return own: the allocated block, state()==MEMORY */ inline buf_block_t *buf_block_alloc(); /********************************************************************//** Frees a buffer block which does not contain a file page. */ @@ -206,71 +156,37 @@ buf_block_free( /*===========*/ buf_block_t* block); /*!< in, own: block to be freed */ -/**************************************************************//** -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(ID, SIZE, LA, MTR) \ - buf_page_get_gen(ID, SIZE, LA, NULL, BUF_GET, __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_get_with_no_latch(ID, SIZE, MTR) \ - buf_page_get_gen(ID, SIZE, RW_NO_LATCH, NULL, BUF_GET_NO_LATCH, \ - __FILE__, __LINE__, MTR) -/********************************************************************//** -This is the general function used to get optimistic access to a database -page. -@return TRUE if success */ -ibool -buf_page_optimistic_get( -/*====================*/ - ulint rw_latch,/*!< in: RW_S_LATCH, RW_X_LATCH */ - buf_block_t* block, /*!< in: guessed block */ - ib_uint64_t modify_clock,/*!< in: modify clock value */ - const char* file, /*!< in: file name */ - unsigned line, /*!< in: line where called */ - mtr_t* mtr); /*!< in: mini-transaction */ - -/** 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. -@param[in] page_id page id -@param[in] file file name -@param[in] line line where called -@param[in] mtr mini-transaction -@return pointer to a page or NULL */ -buf_block_t* -buf_page_try_get_func( - const page_id_t page_id, - const char* file, - unsigned line, - mtr_t* 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. + buf_page_get_gen(ID, SIZE, LA, NULL, BUF_GET, MTR) + +/** Try to acquire a page latch. +@param rw_latch RW_S_LATCH or RW_X_LATCH +@param block guessed block +@param modify_clock expected value of block->modify_clock +@param mtr mini-transaction +@return whether the latch was acquired (the page is an allocated file page) */ +bool buf_page_optimistic_get(ulint rw_latch, buf_block_t *block, + uint64_t modify_clock, mtr_t *mtr); + +/** Try to S-latch a page. +Suitable for using when holding the lock_sys latches (as it avoids deadlock). @param[in] page_id page identifier -@param[in] mtr mini-transaction -@return the page if in buffer pool, NULL if not */ -#define buf_page_try_get(page_id, mtr) \ - buf_page_try_get_func((page_id), __FILE__, __LINE__, mtr); +@param[in,out] mtr mini-transaction +@return the block +@retval nullptr if an S-latch cannot be granted immediately */ +buf_block_t *buf_page_try_get(const page_id_t page_id, mtr_t *mtr); /** 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(). +The page must be released with unfix(). 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. -@param[in] page_id page id -@param[in] zip_size ROW_FORMAT=COMPRESSED page size -@return pointer to the block */ -buf_page_t* buf_page_get_zip(const page_id_t page_id, ulint zip_size); +@param page_id page identifier +@param zip_size ROW_FORMAT=COMPRESSED page size in bytes +@return pointer to the block, s-latched */ +buf_page_t *buf_page_get_zip(const page_id_t page_id, ulint zip_size); /** Get access to a database page. Buffered redo log may be applied. @param[in] page_id page id @@ -278,10 +194,8 @@ buf_page_t* buf_page_get_zip(const page_id_t page_id, ulint zip_size); @param[in] rw_latch RW_S_LATCH, RW_X_LATCH, RW_NO_LATCH @param[in] guess guessed block or NULL @param[in] mode BUF_GET, BUF_GET_IF_IN_POOL, -BUF_PEEK_IF_IN_POOL, BUF_GET_NO_LATCH, or BUF_GET_IF_IN_POOL_OR_WATCH -@param[in] file file name -@param[in] line line where called -@param[in] mtr mini-transaction +BUF_PEEK_IF_IN_POOL, or BUF_GET_IF_IN_POOL_OR_WATCH +@param[in,out] mtr mini-transaction @param[out] err DB_SUCCESS or error code @param[in] allow_ibuf_merge Allow change buffer merge while reading the pages from file. @@ -293,11 +207,10 @@ buf_page_get_gen( ulint rw_latch, buf_block_t* guess, ulint mode, - const char* file, - unsigned line, mtr_t* mtr, dberr_t* err = NULL, - bool allow_ibuf_merge = false); + bool allow_ibuf_merge = false) + MY_ATTRIBUTE((nonnull(6), warn_unused_result)); /** This is the low level function used to get access to a database page. @param[in] page_id page id @@ -305,10 +218,9 @@ buf_page_get_gen( @param[in] rw_latch RW_S_LATCH, RW_X_LATCH, RW_NO_LATCH @param[in] guess guessed block or NULL @param[in] mode BUF_GET, BUF_GET_IF_IN_POOL, -BUF_PEEK_IF_IN_POOL, BUF_GET_NO_LATCH, or BUF_GET_IF_IN_POOL_OR_WATCH -@param[in] file file name -@param[in] line line where called -@param[in] mtr mini-transaction +BUF_PEEK_IF_IN_POOL, or BUF_GET_IF_IN_POOL_OR_WATCH +@param[in,out] mtr mini-transaction, or NULL if a + block with page_id is to be evicted @param[out] err DB_SUCCESS or error code @param[in] allow_ibuf_merge Allow change buffer merge to happen while reading the page from file @@ -322,16 +234,14 @@ buf_page_get_low( ulint rw_latch, buf_block_t* guess, ulint mode, - const char* file, - unsigned line, mtr_t* mtr, dberr_t* err, bool allow_ibuf_merge); /** Initialize a page in the buffer 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). +of the functions which perform to a block a state transition NOT_USED => LRU +(the other is buf_page_get_low()). @param[in,out] space space object @param[in] offset offset of the tablespace @param[in] zip_size ROW_FORMAT=COMPRESSED page size, or 0 @@ -342,52 +252,24 @@ buf_block_t* buf_page_create(fil_space_t *space, uint32_t offset, ulint zip_size, mtr_t *mtr, buf_block_t *free_block); -/********************************************************************//** -Releases a compressed-only page acquired with buf_page_get_zip(). */ -UNIV_INLINE -void -buf_page_release_zip( -/*=================*/ - buf_page_t* bpage); /*!< in: buffer block */ -/********************************************************************//** -Releases a latch, if specified. */ -UNIV_INLINE -void -buf_page_release_latch( -/*=====================*/ - buf_block_t* block, /*!< in: buffer block */ - ulint rw_latch); /*!< in: RW_S_LATCH, RW_X_LATCH, - RW_NO_LATCH */ +/** Initialize a page in buffer pool while initializing the +deferred tablespace +@param space_id space identfier +@param zip_size ROW_FORMAT=COMPRESSED page size or 0 +@param mtr mini-transaction +@param free_block pre-allocated buffer block +@return pointer to the block, page bufferfixed */ +buf_block_t* +buf_page_create_deferred(uint32_t space_id, ulint zip_size, mtr_t *mtr, + buf_block_t *free_block); + /** Move a block to the start of the LRU list. */ void buf_page_make_young(buf_page_t *bpage); -/** Mark the page status as FREED for the given tablespace id and -page number. If the page is not in buffer pool then ignore it. +/** Mark the page status as FREED for the given tablespace and page number. @param[in,out] space tablespace @param[in] page page number -@param[in,out] mtr mini-transaction -@param[in] file file name -@param[in] line line where called */ -void buf_page_free(fil_space_t *space, uint32_t page, mtr_t *mtr, - const char *file, unsigned line); - -/********************************************************************//** -Reads the freed_page_clock of a buffer block. -@return freed_page_clock */ -UNIV_INLINE -unsigned -buf_page_get_freed_page_clock( -/*==========================*/ - const buf_page_t* bpage) /*!< in: block */ - MY_ATTRIBUTE((warn_unused_result)); -/********************************************************************//** -Reads the freed_page_clock of a buffer block. -@return freed_page_clock */ -UNIV_INLINE -unsigned -buf_block_get_freed_page_clock( -/*===========================*/ - const buf_block_t* block) /*!< in: block */ - MY_ATTRIBUTE((warn_unused_result)); +@param[in,out] mtr mini-transaction */ +void buf_page_free(fil_space_t *space, uint32_t page, mtr_t *mtr); /** Determine 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 @@ -431,32 +313,6 @@ ib_uint64_t buf_block_get_modify_clock( /*=======================*/ buf_block_t* block); /*!< in: block */ -/*******************************************************************//** -Increments the bufferfix count. */ -UNIV_INLINE -void -buf_block_buf_fix_inc_func( -/*=======================*/ -# ifdef UNIV_DEBUG - const char* file, /*!< in: file name */ - unsigned line, /*!< in: line */ -# endif /* UNIV_DEBUG */ - buf_block_t* block) /*!< in/out: block to bufferfix */ - MY_ATTRIBUTE((nonnull)); - -# ifdef UNIV_DEBUG -/** Increments the bufferfix count. -@param[in,out] b block to bufferfix -@param[in] f file name where requested -@param[in] l line number where requested */ -# define buf_block_buf_fix_inc(b,f,l) buf_block_buf_fix_inc_func(f,l,b) -# else /* UNIV_DEBUG */ -/** Increments the bufferfix count. -@param[in,out] b block to bufferfix -@param[in] f file name where requested -@param[in] l line number where requested */ -# define buf_block_buf_fix_inc(b,f,l) buf_block_buf_fix_inc_func(b) -# endif /* UNIV_DEBUG */ #endif /* !UNIV_INNOCHECKSUM */ /** Check if a buffer is all zeroes. @@ -464,42 +320,6 @@ buf_block_buf_fix_inc_func( @return whether the buffer is all zeroes */ bool buf_is_zeroes(st_::span<const byte> buf); -/** Checks if the page is in crc32 checksum format. -@param[in] read_buf database page -@param[in] checksum_field1 new checksum field -@param[in] checksum_field2 old checksum field -@return true if the page is in crc32 checksum format. */ -bool -buf_page_is_checksum_valid_crc32( - const byte* read_buf, - ulint checksum_field1, - ulint checksum_field2) - MY_ATTRIBUTE((nonnull(1), warn_unused_result)); - -/** Checks if the page is in innodb checksum format. -@param[in] read_buf database page -@param[in] checksum_field1 new checksum field -@param[in] checksum_field2 old checksum field -@return true if the page is in innodb checksum format. */ -bool -buf_page_is_checksum_valid_innodb( - const byte* read_buf, - ulint checksum_field1, - ulint checksum_field2) - MY_ATTRIBUTE((nonnull(1), warn_unused_result)); - -/** Checks if the page is in none checksum format. -@param[in] read_buf database page -@param[in] checksum_field1 new checksum field -@param[in] checksum_field2 old checksum field -@return true if the page is in none checksum format. */ -bool -buf_page_is_checksum_valid_none( - const byte* read_buf, - ulint checksum_field1, - ulint checksum_field2) - MY_ATTRIBUTE((nonnull(1), warn_unused_result)); - /** Check if a page is corrupt. @param[in] check_lsn whether the LSN should be checked @param[in] read_buf database page @@ -512,27 +332,6 @@ buf_page_is_corrupted( ulint fsp_flags) MY_ATTRIBUTE((warn_unused_result)); -inline void *aligned_malloc(size_t size, size_t align) -{ -#ifdef _MSC_VER - return _aligned_malloc(size, align); -#else - void *result; - if (posix_memalign(&result, align, size)) - result= NULL; - return result; -#endif -} - -inline void aligned_free(void *ptr) -{ -#ifdef _MSC_VER - _aligned_free(ptr); -#else - free(ptr); -#endif -} - /** Read the key version from the page. In full crc32 format, key version is stored at {0-3th} bytes. In other format, it is stored in 26th position. @@ -631,35 +430,7 @@ void buf_pool_invalidate(); --------------------------- LOWER LEVEL ROUTINES ------------------------- =========================================================================*/ -#ifdef UNIV_DEBUG -/*********************************************************************//** -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. */ -UNIV_INLINE -void -buf_block_dbg_add_level( -/*====================*/ - buf_block_t* block, /*!< in: buffer page - where we have acquired latch */ - latch_level_t level); /*!< in: latching order level */ -#else /* UNIV_DEBUG */ -# define buf_block_dbg_add_level(block, level) /* nothing */ -#endif /* UNIV_DEBUG */ - -#ifdef UNIV_DEBUG -/*********************************************************************//** -Gets a pointer to the memory frame of a block. -@return pointer to the frame */ -UNIV_INLINE -buf_frame_t* -buf_block_get_frame( -/*================*/ - const buf_block_t* block) /*!< in: pointer to the control block */ - MY_ATTRIBUTE((warn_unused_result)); -#else /* UNIV_DEBUG */ -# define buf_block_get_frame(block) (block)->frame -#endif /* UNIV_DEBUG */ +#define buf_block_get_frame(block) (block)->page.frame /*********************************************************************//** Gets the compressed page descriptor corresponding to an uncompressed page @@ -672,18 +443,8 @@ if applicable. */ /** Monitor the buffer page read/write activity, and increment corresponding counter value in MONITOR_MODULE_BUF_PAGE. @param bpage buffer page whose read or write was completed -@param io_type BUF_IO_READ or BUF_IO_WRITE */ -ATTRIBUTE_COLD __attribute__((nonnull)) -void buf_page_monitor(const buf_page_t *bpage, buf_io_fix io_type); - -/** Complete a read request of a file page to buf_pool. -@param bpage recently read page -@param node data file -@return whether the operation succeeded -@retval DB_SUCCESS always when writing, or if a read page was OK -@retval DB_PAGE_CORRUPTED if the checksum fails on a page read -@retval DB_DECRYPTION_FAILED if the page cannot be decrypted */ -dberr_t buf_page_read_complete(buf_page_t *bpage, const fil_node_t &node); +@param read true=read, false=write */ +ATTRIBUTE_COLD void buf_page_monitor(const buf_page_t &bpage, bool read); /** Calculate aligned buffer pool size based on srv_buf_pool_chunk_unit, if needed. @@ -752,17 +513,17 @@ class buf_page_t { friend buf_pool_t; friend buf_block_t; + /** @name General fields */ /* @{ */ public: // FIXME: fix fil_iterate() - /** Page id. Protected by buf_pool.hash_lock_get(id) when + /** Page id. Protected by buf_pool.page_hash.lock_get() when the page is in buf_pool.page_hash. */ page_id_t id_; + /** buf_pool.page_hash link; protected by buf_pool.page_hash.lock_get() */ + buf_page_t *hash; private: - /** Count of how manyfold this block is currently bufferfixed. */ - Atomic_counter<uint32_t> buf_fix_count_; - /** log sequence number of the START of the log entry written of the oldest modification to this block which has not yet been written to the data file; @@ -773,53 +534,64 @@ private: (because id().space() is the temporary tablespace). */ Atomic_relaxed<lsn_t> oldest_modification_; - /** type of pending I/O operation; protected by buf_pool.mutex - if in_LRU_list */ - Atomic_relaxed<buf_io_fix> io_fix_; - /** Block state. @see in_file(). - State transitions between in_file() states and to - BUF_BLOCK_REMOVE_HASH are protected by buf_pool.hash_lock_get(id) - when the block is in buf_pool.page_hash. - Other transitions when in_LRU_list are protected by buf_pool.mutex. */ - buf_page_state state_; - public: - /** buf_pool.page_hash link; protected by buf_pool.hash_lock_get(id) */ - buf_page_t *hash; + /** state() of unused block (in buf_pool.free list) */ + static constexpr uint32_t NOT_USED= 0; + /** state() of block allocated as general-purpose memory */ + static constexpr uint32_t MEMORY= 1; + /** state() of block that is being freed */ + static constexpr uint32_t REMOVE_HASH= 2; + /** smallest state() of a buffer page that is freed in the tablespace */ + static constexpr uint32_t FREED= 3; + /** smallest state() for a block that belongs to buf_pool.LRU */ + static constexpr uint32_t UNFIXED= 1U << 29; + /** smallest state() of a block for which buffered changes may exist */ + static constexpr uint32_t IBUF_EXIST= 2U << 29; + /** smallest state() of a (re)initialized page (no doublewrite needed) */ + static constexpr uint32_t REINIT= 3U << 29; + /** smallest state() for an io-fixed block */ + static constexpr uint32_t READ_FIX= 4U << 29; + /** smallest state() for a write-fixed block */ + static constexpr uint32_t WRITE_FIX= 5U << 29; + /** smallest state() for a write-fixed block with buffered changes */ + static constexpr uint32_t WRITE_FIX_IBUF= 6U << 29; + /** smallest state() for a write-fixed block (no doublewrite was used) */ + static constexpr uint32_t WRITE_FIX_REINIT= 7U << 29; + /** buf_pool.LRU status mask in state() */ + static constexpr uint32_t LRU_MASK= 7U << 29; + + /** lock covering the contents of frame */ + block_lock lock; + /** pointer to aligned, uncompressed page frame of innodb_page_size */ + byte *frame; /* @} */ - page_zip_des_t zip; /*!< compressed page; zip.data - (but not the data it points to) is - also protected by buf_pool.mutex; - state == BUF_BLOCK_ZIP_PAGE and - zip.data == NULL means an active - buf_pool.watch */ - - buf_tmp_buffer_t* slot; /*!< Slot for temporary memory - used for encryption/compression - or NULL */ + /** ROW_FORMAT=COMPRESSED page; zip.data (but not the data it points to) + is also protected by buf_pool.mutex; + !frame && !zip.data means an active buf_pool.watch */ + page_zip_des_t zip; #ifdef UNIV_DEBUG /** whether this->list is in buf_pool.zip_hash; protected by buf_pool.mutex */ bool in_zip_hash; - /** whether this->LRU is in buf_pool.LRU (in_file() holds); + /** whether this->LRU is in buf_pool.LRU (in_file()); protected by buf_pool.mutex */ bool in_LRU_list; - /** whether this is in buf_pool.page_hash (in_file() holds); + /** whether this is in buf_pool.page_hash (in_file()); protected by buf_pool.mutex */ bool in_page_hash; - /** whether this->list is in buf_pool.free (state() == BUF_BLOCK_NOT_USED); + /** whether this->list is in buf_pool.free (state() == NOT_USED); protected by buf_pool.flush_list_mutex */ bool in_free_list; #endif /* UNIV_DEBUG */ /** list member in one of the lists of buf_pool; protected by buf_pool.mutex or buf_pool.flush_list_mutex - state() == BUF_BLOCK_NOT_USED: buf_pool.free or buf_pool.withdraw + state() == NOT_USED: buf_pool.free or buf_pool.withdraw in_file() && oldest_modification(): buf_pool.flush_list (protected by buf_pool.flush_list_mutex) The contents is undefined if in_file() && !oldest_modification(), - or if state() is BUF_BLOCK_MEMORY or BUF_BLOCK_REMOVE_HASH. */ + or if state() == MEMORY or state() == REMOVE_HASH. */ UT_LIST_NODE_T(buf_page_t) list; /** @name LRU replacement algorithm fields. @@ -843,7 +615,7 @@ public: 0 if the block was never accessed in the buffer pool. - For state==BUF_BLOCK_MEMORY + For state() == MEMORY blocks, this field can be repurposed for something else. @@ -851,89 +623,127 @@ public: and bytes allocated for recv_sys.pages, the field is protected by recv_sys_t::mutex. */ - /** Change buffer entries for the page exist. - Protected by io_fix()==BUF_IO_READ or by buf_block_t::lock. */ - bool ibuf_exist; - - /** Block initialization status. Can be modified while holding io_fix() - or buf_block_t::lock X-latch */ - enum { - /** the page was read normally and should be flushed normally */ - NORMAL = 0, - /** the page was (re)initialized, and the doublewrite buffer can be - skipped on the next flush */ - INIT_ON_FLUSH, - /** the page was freed and need to be flushed. - For page_compressed, page flush will punch a hole to free space. - Else if innodb_immediate_scrub_data_uncompressed, the page will - be overwritten with zeroes. */ - FREED - } status; - - buf_page_t() : id_(0) + buf_page_t() : id_{0} { - static_assert(BUF_BLOCK_NOT_USED == 0, "compatibility"); + static_assert(NOT_USED == 0, "compatibility"); memset((void*) this, 0, sizeof *this); } - /** Initialize some fields */ - void init() + buf_page_t(const buf_page_t &b) : + id_(b.id_), hash(b.hash), + oldest_modification_(b.oldest_modification_), + lock() /* not copied */, + frame(b.frame), zip(b.zip), +#ifdef UNIV_DEBUG + in_zip_hash(b.in_zip_hash), in_LRU_list(b.in_LRU_list), + in_page_hash(b.in_page_hash), in_free_list(b.in_free_list), +#endif /* UNIV_DEBUG */ + list(b.list), LRU(b.LRU), old(b.old), freed_page_clock(b.freed_page_clock), + access_time(b.access_time) { - io_fix_= BUF_IO_NONE; - buf_fix_count_= 0; - old= 0; - freed_page_clock= 0; - access_time= 0; + lock.init(); + } + + /** Initialize some more fields */ + void init(uint32_t state, page_id_t id) + { + ut_ad(state < REMOVE_HASH || state >= UNFIXED); + id_= id; + zip.fix= state; oldest_modification_= 0; - slot= nullptr; - ibuf_exist= false; - status= NORMAL; + lock.init(); ut_d(in_zip_hash= false); ut_d(in_free_list= false); ut_d(in_LRU_list= false); ut_d(in_page_hash= false); - HASH_INVALIDATE(this, hash); + old= 0; + freed_page_clock= 0; + access_time= 0; } - /** Initialize some more fields */ - void init(buf_page_state state, page_id_t id, uint32_t buf_fix_count= 0) +public: + const page_id_t &id() const { return id_; } + uint32_t state() const { return zip.fix; } + uint32_t buf_fix_count() const { - init(); - state_= state; - id_= id; - buf_fix_count_= buf_fix_count; + uint32_t f= state(); + ut_ad(f >= FREED); + return f < UNFIXED ? (f - FREED) : (~LRU_MASK & f); } + /** @return whether this block is read or write fixed; + read_complete() or write_complete() will always release + the io-fix before releasing U-lock or X-lock */ + bool is_io_fixed() const + { const auto s= state(); ut_ad(s >= FREED); return s >= READ_FIX; } + /** @return whether this block is write fixed; + write_complete() will always release the write-fix before releasing U-lock */ + bool is_write_fixed() const { return state() >= WRITE_FIX; } + /** @return whether this block is read fixed; this should never hold + when a thread is holding the block lock in any mode */ + bool is_read_fixed() const { return is_io_fixed() && !is_write_fixed(); } - /** Initialize some more fields */ - void init(page_id_t id, uint32_t buf_fix_count= 0) + /** @return if this belongs to buf_pool.unzip_LRU */ + bool belongs_to_unzip_LRU() const + { return UNIV_LIKELY_NULL(zip.data) && frame; } + + bool is_freed() const + { const auto s= state(); ut_ad(s >= FREED); return s < UNFIXED; } + bool is_ibuf_exist() const { - init(); - id_= id; - buf_fix_count_= buf_fix_count; + const auto s= state(); + ut_ad(s >= UNFIXED); + ut_ad(s < READ_FIX); + return (s & LRU_MASK) == IBUF_EXIST; } + bool is_reinit() const { return !(~state() & REINIT); } -public: - const page_id_t &id() const { return id_; } - buf_page_state state() const { return state_; } - uint32_t buf_fix_count() const { return buf_fix_count_; } - buf_io_fix io_fix() const { return io_fix_; } - void io_unfix() + void set_reinit(uint32_t prev_state) { - ut_d(const auto old_io_fix= io_fix()); - ut_ad(old_io_fix == BUF_IO_READ || old_io_fix == BUF_IO_PIN); - io_fix_= BUF_IO_NONE; + ut_ad(prev_state < READ_FIX); + ut_d(const auto s=) zip.fix.fetch_add(REINIT - prev_state); + ut_ad(s > prev_state); + ut_ad(s < prev_state + UNFIXED); } - /** @return if this belongs to buf_pool.unzip_LRU */ - bool belongs_to_unzip_LRU() const + void set_ibuf_exist() + { + ut_ad(lock.is_write_locked()); + ut_ad(id() < page_id_t(SRV_SPACE_ID_UPPER_BOUND, 0)); + const auto s= state(); + ut_ad(s >= UNFIXED); + ut_ad(s < READ_FIX); + ut_ad(s < IBUF_EXIST || s >= REINIT); + zip.fix.fetch_add(IBUF_EXIST - (LRU_MASK & s)); + } + void clear_ibuf_exist() + { + ut_ad(lock.is_write_locked()); + ut_ad(id() < page_id_t(SRV_SPACE_ID_UPPER_BOUND, 0)); + ut_d(const auto s=) zip.fix.fetch_sub(IBUF_EXIST - UNFIXED); + ut_ad(s >= IBUF_EXIST); + ut_ad(s < REINIT); + } + + uint32_t read_unfix(uint32_t s) { - return zip.data && state() != BUF_BLOCK_ZIP_PAGE; + ut_ad(lock.is_write_locked()); + ut_ad(s == UNFIXED + 1 || s == IBUF_EXIST + 1 || s == REINIT + 1); + uint32_t old_state= zip.fix.fetch_add(s - READ_FIX); + ut_ad(old_state >= READ_FIX); + ut_ad(old_state < WRITE_FIX); + return old_state + (s - READ_FIX); } - inline void add_buf_fix_count(uint32_t count); - inline void set_buf_fix_count(uint32_t count); - inline void set_state(buf_page_state state); - inline void set_io_fix(buf_io_fix io_fix); + void set_freed(uint32_t prev_state, uint32_t count= 0) + { + ut_ad(lock.is_write_locked()); + ut_ad(prev_state >= UNFIXED); + ut_ad(prev_state < READ_FIX); + ut_d(auto s=) zip.fix.fetch_sub((prev_state & LRU_MASK) - FREED - count); + ut_ad(!((prev_state ^ s) & LRU_MASK)); + } + + inline void set_state(uint32_t s); inline void set_corrupt_id(); /** @return the log sequence number of the oldest pending modification @@ -953,35 +763,72 @@ public: inline void set_oldest_modification(lsn_t lsn); /** Clear oldest_modification after removing from buf_pool.flush_list */ inline void clear_oldest_modification(); + /** Reset the oldest_modification when marking a persistent page freed */ + void reset_oldest_modification() + { + ut_ad(oldest_modification() > 2); + oldest_modification_.store(1, std::memory_order_release); + } + + /** Complete a read of a page. + @param node data file + @return whether the operation succeeded + @retval DB_PAGE_CORRUPTED if the checksum fails + @retval DB_DECRYPTION_FAILED if the page cannot be decrypted + @retval DB_FAIL if the page contains the wrong ID */ + dberr_t read_complete(const fil_node_t &node); + /** Note that a block is no longer dirty, while not removing it from buf_pool.flush_list */ - inline void clear_oldest_modification(bool temporary); + inline void write_complete(bool temporary); + + /** Write a flushable page to a file or free a freeable block. + @param evict whether to evict the page on write completion + @param space tablespace + @return whether a page write was initiated and buf_pool.mutex released */ + bool flush(bool evict, fil_space_t *space); /** Notify that a page in a temporary tablespace has been modified. */ void set_temp_modified() { ut_ad(fsp_is_system_temporary(id().space())); - ut_ad(state() == BUF_BLOCK_FILE_PAGE); - ut_ad(!oldest_modification()); + ut_ad(in_file()); + ut_ad((oldest_modification() | 2) == 2); oldest_modification_= 2; } /** Prepare to release a file page to buf_pool.free. */ void free_file_page() { - ut_ad(state() == BUF_BLOCK_REMOVE_HASH); + ut_ad((zip.fix.fetch_sub(REMOVE_HASH - MEMORY)) == REMOVE_HASH); /* buf_LRU_block_free_non_file_page() asserts !oldest_modification() */ ut_d(oldest_modification_= 0;) - set_corrupt_id(); - ut_d(set_state(BUF_BLOCK_MEMORY)); + id_= page_id_t(~0ULL); + } + + void fix_on_recovery() + { + ut_d(const auto f=) zip.fix.fetch_sub(READ_FIX - UNFIXED - 1); + ut_ad(f >= READ_FIX); + ut_ad(f < WRITE_FIX); + } + + uint32_t fix(uint32_t count= 1) + { + ut_ad(count); + ut_ad(count < IBUF_EXIST); + uint32_t f= zip.fix.fetch_add(count); + ut_ad(f >= FREED); + ut_ad(!((f ^ (f + 1)) & LRU_MASK)); + return f; } - void fix() { buf_fix_count_++; } uint32_t unfix() { - uint32_t count= buf_fix_count_--; - ut_ad(count != 0); - return count - 1; + uint32_t f= zip.fix.fetch_sub(1); + ut_ad(f > FREED); + ut_ad(!((f ^ (f - 1)) & LRU_MASK)); + return f - 1; } /** @return the physical size, in bytes */ @@ -1007,27 +854,8 @@ public: } /** @return whether the block is mapped to a data file */ - bool in_file() const - { - switch (state_) { - case BUF_BLOCK_ZIP_PAGE: - case BUF_BLOCK_FILE_PAGE: - return true; - case BUF_BLOCK_NOT_USED: - case BUF_BLOCK_MEMORY: - case BUF_BLOCK_REMOVE_HASH: - return false; - } + bool in_file() const { return state() >= FREED; } - ut_error; - return false; - } - - /** @return whether the block is modified and ready for flushing */ - inline bool ready_for_flush() const; - /** @return whether the state can be changed to BUF_BLOCK_NOT_USED */ - bool ready_for_replace() const - { return !oldest_modification() && can_relocate(); } /** @return whether the block can be relocated in memory. The block can be dirty, but it must not be I/O-fixed or bufferfixed. */ inline bool can_relocate() const; @@ -1059,27 +887,18 @@ struct buf_block_t{ be the first field, so that buf_pool.page_hash can point to buf_page_t or buf_block_t */ - byte* frame; /*!< pointer to buffer frame which - is of size srv_page_size, and - aligned to an address divisible by - srv_page_size */ - rw_lock_t lock; /*!< read-write lock of the buffer - frame */ #ifdef UNIV_DEBUG /** whether page.list is in buf_pool.withdraw - ((state() == BUF_BLOCK_NOT_USED)) and the buffer pool is being shrunk; + ((state() == NOT_USED)) and the buffer pool is being shrunk; protected by buf_pool.mutex */ bool in_withdraw_list; /** whether unzip_LRU is in buf_pool.unzip_LRU - (state() == BUF_BLOCK_FILE_PAGE and zip.data != nullptr); + (in_file() && frame && zip.data); protected by buf_pool.mutex */ bool in_unzip_LRU_list; #endif - UT_LIST_NODE_T(buf_block_t) unzip_LRU; - /*!< node of the decompressed LRU list; - a block is in the unzip_LRU list - if page.state() == BUF_BLOCK_FILE_PAGE - and page.zip.data != NULL */ + /** member of buf_pool.unzip_LRU (if belongs_to_unzip_LRU()) */ + UT_LIST_NODE_T(buf_block_t) unzip_LRU; /* @} */ /** @name Optimistic search field */ /* @{ */ @@ -1118,17 +937,15 @@ struct buf_block_t{ These 5 fields may only be modified when: we are holding the appropriate x-latch in btr_search_latches[], and one of the following holds: - (1) the block state is BUF_BLOCK_FILE_PAGE, and - we are holding an s-latch or x-latch on buf_block_t::lock, or - (2) buf_block_t::buf_fix_count == 0, or - (3) the block state is BUF_BLOCK_REMOVE_HASH. + (1) in_file(), and we are holding lock in any mode, or + (2) !is_read_fixed()&&(state()>=UNFIXED||state()==REMOVE_HASH). An exception to this is when we init or create a page in the buffer pool in buf0buf.cc. Another exception for buf_pool_t::clear_hash_index() is that assigning block->index = NULL (and block->n_pointers = 0) - is allowed whenever btr_search_own_all(RW_LOCK_X). + is allowed whenever all AHI latches are exclusively locked. Another exception is that ha_insert_for_fold() may decrement n_pointers without holding the appropriate latch @@ -1137,8 +954,8 @@ struct buf_block_t{ This implies that the fields may be read without race condition whenever any of the following hold: - - the btr_search_latches[] s-latch or x-latch is being held, or - - the block state is not BUF_BLOCK_FILE_PAGE or BUF_BLOCK_REMOVE_HASH, + - the btr_search_sys.partition[].latch is being held, or + - state() == NOT_USED || state() == MEMORY, and holding some latch prevents the state from changing to that. Some use of assert_block_ahi_empty() or assert_block_ahi_valid() @@ -1152,9 +969,7 @@ struct buf_block_t{ Atomic_counter<ulint> n_pointers; /*!< used in debugging: the number of pointers in the adaptive hash index - pointing to this frame; - protected by atomic memory access - or btr_search_own_all(). */ + pointing to this frame */ # define assert_block_ahi_empty(block) \ ut_a((block)->n_pointers == 0) # define assert_block_ahi_empty_on_init(block) do { \ @@ -1188,24 +1003,8 @@ struct buf_block_t{ # define assert_block_ahi_empty_on_init(block) /* nothing */ # define assert_block_ahi_valid(block) /* nothing */ #endif /* BTR_CUR_HASH_ADAPT */ -# ifdef UNIV_DEBUG - /** @name Debug fields */ - /* @{ */ - rw_lock_t* debug_latch; /*!< in the debug version, each thread - which bufferfixes the block acquires - an s-latch here; so we can use the - debug utilities in sync0rw */ - /* @} */ -# endif void fix() { page.fix(); } - uint32_t unfix() - { - ut_ad(page.buf_fix_count() || page.io_fix() != BUF_IO_NONE || - page.state() == BUF_BLOCK_ZIP_PAGE || - !rw_lock_own_flagged(&lock, RW_LOCK_FLAG_X | RW_LOCK_FLAG_S | - RW_LOCK_FLAG_SX)); - return page.unfix(); - } + uint32_t unfix() { return page.unfix(); } /** @return the physical size, in bytes */ ulint physical_size() const { return page.physical_size(); } @@ -1217,22 +1016,22 @@ struct buf_block_t{ /** Initialize the block. @param page_id page identifier @param zip_size ROW_FORMAT=COMPRESSED page size, or 0 - @param fix initial buf_fix_count() */ - void initialise(const page_id_t page_id, ulint zip_size, uint32_t fix= 0); + @param state initial state() */ + void initialise(const page_id_t page_id, ulint zip_size, uint32_t state); }; /**********************************************************************//** Compute the hash fold value for blocks in buf_pool.zip_hash. */ /* @{ */ #define BUF_POOL_ZIP_FOLD_PTR(ptr) (ulint(ptr) >> srv_page_size_shift) -#define BUF_POOL_ZIP_FOLD(b) BUF_POOL_ZIP_FOLD_PTR((b)->frame) +#define BUF_POOL_ZIP_FOLD(b) BUF_POOL_ZIP_FOLD_PTR((b)->page.frame) #define BUF_POOL_ZIP_FOLD_BPAGE(b) BUF_POOL_ZIP_FOLD((buf_block_t*) (b)) /* @} */ -/** A "Hazard Pointer" class used to iterate over page lists -inside the buffer pool. A hazard pointer is a buf_page_t pointer +/** A "Hazard Pointer" class used to iterate over buf_pool.LRU or +buf_pool.flush_list. A hazard pointer is a buf_page_t pointer which we intend to iterate over next and we want it remain valid -even after we release the buffer pool mutex. */ +even after we release the mutex that protects the list. */ class HazardPointer { public: @@ -1347,14 +1146,18 @@ struct buf_buddy_free_t { /*!< Node of zip_free list */ }; -/** @brief The buffer pool statistics structure. */ +/** @brief The buffer pool statistics structure; +protected by buf_pool.mutex unless otherwise noted. */ struct buf_pool_stat_t{ - ulint n_page_gets; /*!< number of page gets performed; + /** Initialize the counters */ + void init() { memset((void*) this, 0, sizeof *this); } + + ib_counter_t<ulint, ib_counter_element_t> n_page_gets; + /*!< number of page gets performed; also successful searches through the adaptive hash index are - counted as page gets; this field - is NOT protected by the buffer - pool mutex */ + counted as page gets; + NOT protected by buf_pool.mutex */ ulint n_pages_read; /*!< number read operations */ ulint n_pages_written;/*!< number write operations */ ulint n_pages_created;/*!< number of pages created @@ -1372,10 +1175,9 @@ struct buf_pool_stat_t{ young because the first access was not long enough ago, in buf_page_peek_if_too_old() */ - /** number of waits for eviction; writes protected by buf_pool.mutex */ + /** number of waits for eviction */ ulint LRU_waits; ulint LRU_bytes; /*!< LRU size in bytes */ - ulint flush_list_bytes;/*!< flush_list size in bytes */ }; /** Statistics of buddy blocks of a given size. */ @@ -1415,7 +1217,7 @@ class buf_pool_t size_t mem_size() const { return mem_pfx.m_size; } /** Register the chunk */ - void reg() { map_reg->emplace(map::value_type(blocks->frame, this)); } + void reg() { map_reg->emplace(map::value_type(blocks->page.frame, this)); } /** Allocate a chunk of buffer frames. @param bytes requested size @@ -1442,7 +1244,14 @@ class buf_pool_t inline const buf_block_t *not_freed() const; #endif /* UNIV_DEBUG */ }; - +public: + /** Hash cell chain in page_hash_table */ + struct hash_chain + { + /** pointer to the first block */ + buf_page_t *first; + }; +private: /** Withdraw blocks from the buffer pool until meeting withdraw_target. @return whether retry is needed */ inline bool withdraw_blocks(); @@ -1494,27 +1303,27 @@ public: { ut_ad(is_initialised()); size_t size= 0; - for (auto j= n_chunks; j--; ) + for (auto j= ut_min(n_chunks_new, n_chunks); j--; ) size+= chunks[j].size; return size; } /** Determine whether a frame is intended to be withdrawn during resize(). - @param ptr pointer within a buf_block_t::frame + @param ptr pointer within a buf_page_t::frame @return whether the frame will be withdrawn */ bool will_be_withdrawn(const byte *ptr) const { - ut_ad(curr_size < old_size); + ut_ad(n_chunks_new < n_chunks); #ifdef SAFE_MUTEX - if (resizing.load(std::memory_order_relaxed)) + if (resize_in_progress()) mysql_mutex_assert_owner(&mutex); #endif /* SAFE_MUTEX */ for (const chunk_t *chunk= chunks + n_chunks_new, * const echunk= chunks + n_chunks; chunk != echunk; chunk++) - if (ptr >= chunk->blocks->frame && - ptr < (chunk->blocks + chunk->size - 1)->frame + srv_page_size) + if (ptr >= chunk->blocks->page.frame && + ptr < (chunk->blocks + chunk->size - 1)->page.frame + srv_page_size) return true; return false; } @@ -1524,9 +1333,9 @@ public: @return whether the frame will be withdrawn */ bool will_be_withdrawn(const buf_page_t &bpage) const { - ut_ad(curr_size < old_size); + ut_ad(n_chunks_new < n_chunks); #ifdef SAFE_MUTEX - if (resizing.load(std::memory_order_relaxed)) + if (resize_in_progress()) mysql_mutex_assert_owner(&mutex); #endif /* SAFE_MUTEX */ @@ -1540,8 +1349,9 @@ public: } /** Release and evict a corrupted page. - @param bpage page that was being read */ - ATTRIBUTE_COLD void corrupted_evict(buf_page_t *bpage); + @param bpage x-latched page that was found corrupted + @param state expected current state of the page */ + ATTRIBUTE_COLD void corrupted_evict(buf_page_t *bpage, uint32_t state); /** Release a memory block to the buffer pool. */ ATTRIBUTE_COLD void free_block(buf_block_t *block); @@ -1576,9 +1386,6 @@ public: inline buf_block_t *block_from_ahi(const byte *ptr) const; #endif /* BTR_CUR_HASH_ADAPT */ - bool is_block_lock(const rw_lock_t *l) const - { return is_block_field(static_cast<const void*>(l)); } - /** @return the smallest oldest_modification lsn for any page @retval empty_lsn if all modified persistent pages have been flushed */ @@ -1607,84 +1414,27 @@ public: return is_block_field(reinterpret_cast<const void*>(block)); } - /** Get the page_hash latch for a page */ - page_hash_latch *hash_lock_get(const page_id_t id) const - { - return page_hash.lock_get(id.fold()); - } - - /** Look up a block descriptor. - @param id page identifier - @param fold id.fold() - @return block descriptor, possibly in watch[] - @retval nullptr if not found*/ - buf_page_t *page_hash_get_low(const page_id_t id, const ulint fold) - { - ut_ad(id.fold() == fold); -#ifdef SAFE_MUTEX - DBUG_ASSERT(mysql_mutex_is_owner(&mutex) || - page_hash.lock_get(fold)->is_locked()); -#endif /* SAFE_MUTEX */ - buf_page_t *bpage; - /* Look for the page in the hash table */ - HASH_SEARCH(hash, &page_hash, fold, buf_page_t*, bpage, - ut_ad(bpage->in_page_hash), id == bpage->id()); - return bpage; - } -private: - /** Look up a block descriptor. - @tparam exclusive whether the latch is to be acquired exclusively - @tparam watch whether to allow watch_is_sentinel() - @param page_id page identifier - @param fold page_id.fold() - @param hash_lock pointer to the acquired latch (to be released by caller) - @return pointer to the block - @retval nullptr if no block was found; !lock || !*lock will also hold */ - template<bool exclusive,bool watch> - buf_page_t *page_hash_get_locked(const page_id_t page_id, ulint fold, - page_hash_latch **hash_lock) +public: + /** @return whether the buffer pool contains a page + @tparam allow_watch whether to allow watch_is_sentinel() + @param page_id page identifier + @param chain hash table chain for page_id.fold() */ + template<bool allow_watch= false> + TRANSACTIONAL_INLINE + bool page_hash_contains(const page_id_t page_id, hash_chain &chain) { - ut_ad(hash_lock || !exclusive); - page_hash_latch *latch= page_hash.lock<exclusive>(fold); - buf_page_t *bpage= page_hash_get_low(page_id, fold); - if (!bpage || watch_is_sentinel(*bpage)) + transactional_shared_lock_guard<page_hash_latch> g + {page_hash.lock_get(chain)}; + buf_page_t *bpage= page_hash.get(page_id, chain); + if (bpage >= &watch[0] && bpage < &watch[UT_ARR_SIZE(watch)]) { - latch->release<exclusive>(); - if (hash_lock) - *hash_lock= nullptr; - return watch ? bpage : nullptr; + ut_ad(!bpage->in_zip_hash); + ut_ad(!bpage->zip.data); + if (!allow_watch) + bpage= nullptr; } - - ut_ad(bpage->in_file()); - ut_ad(page_id == bpage->id()); - - if (hash_lock) - *hash_lock= latch; /* to be released by the caller */ - else - latch->release<exclusive>(); return bpage; } -public: - /** Look up a block descriptor. - @tparam exclusive whether the latch is to be acquired exclusively - @param page_id page identifier - @param fold page_id.fold() - @param hash_lock pointer to the acquired latch (to be released by caller) - @return pointer to the block - @retval nullptr if no block was found; !lock || !*lock will also hold */ - template<bool exclusive> - buf_page_t *page_hash_get_locked(const page_id_t page_id, ulint fold, - page_hash_latch **hash_lock) - { return page_hash_get_locked<exclusive,false>(page_id, fold, hash_lock); } - - /** @return whether the buffer pool contains a page - @tparam watch whether to allow watch_is_sentinel() - @param page_id page identifier */ - template<bool watch= false> - bool page_hash_contains(const page_id_t page_id) - { - return page_hash_get_locked<false,watch>(page_id, page_id.fold(), nullptr); - } /** Determine if a block is a sentinel for a buffer pool watch. @param bpage page descriptor @@ -1693,17 +1443,12 @@ public: { #ifdef SAFE_MUTEX DBUG_ASSERT(mysql_mutex_is_owner(&mutex) || - hash_lock_get(bpage.id())->is_locked()); + page_hash.lock_get(page_hash.cell_get(bpage.id().fold())). + is_locked()); #endif /* SAFE_MUTEX */ ut_ad(bpage.in_file()); - - if (&bpage < &watch[0] || &bpage >= &watch[UT_ARR_SIZE(watch)]) - { - ut_ad(bpage.state() != BUF_BLOCK_ZIP_PAGE || bpage.zip.data); + if (&bpage < &watch[0] || &bpage >= &watch[array_elements(watch)]) return false; - } - - ut_ad(bpage.state() == BUF_BLOCK_ZIP_PAGE); ut_ad(!bpage.in_zip_hash); ut_ad(!bpage.zip.data); return true; @@ -1713,44 +1458,55 @@ public: This may only be called after !watch_set() and before invoking watch_unset(). @param id page identifier @return whether the page was read to the buffer pool */ + TRANSACTIONAL_INLINE bool watch_occurred(const page_id_t id) { - const ulint fold= id.fold(); - page_hash_latch *hash_lock= page_hash.lock<false>(fold); + hash_chain &chain= page_hash.cell_get(id.fold()); + transactional_shared_lock_guard<page_hash_latch> g + {page_hash.lock_get(chain)}; /* The page must exist because watch_set() increments buf_fix_count. */ - buf_page_t *bpage= page_hash_get_low(id, fold); - const bool is_sentinel= watch_is_sentinel(*bpage); - hash_lock->read_unlock(); - return !is_sentinel; + return !watch_is_sentinel(*page_hash.get(id, chain)); } - /** Register a watch for a page identifier. The caller must hold an - exclusive page hash latch. The *hash_lock may be released, - relocated, and reacquired. + /** Register a watch for a page identifier. @param id page identifier - @param hash_lock exclusively held page_hash latch - @return a buffer pool block corresponding to id - @retval nullptr if the block was not present, and a watch was installed */ - inline buf_page_t *watch_set(const page_id_t id, - page_hash_latch **hash_lock); + @param chain page_hash.cell_get(id.fold()) + @return a buffer page corresponding to id + @retval nullptr if the block was not present in page_hash */ + buf_page_t *watch_set(const page_id_t id, hash_chain &chain); /** Stop watching whether a page has been read in. watch_set(id) must have returned nullptr before. - @param id page identifier */ - void watch_unset(const page_id_t id); + @param id page identifier + @param chain unlocked hash table chain */ + void watch_unset(const page_id_t id, hash_chain &chain); /** Remove the sentinel block for the watch before replacing it with a real block. watch_unset() or watch_occurred() will notice that the block has been replaced with the real block. - @param watch sentinel */ - inline void watch_remove(buf_page_t *watch); + @param w sentinel + @param chain locked hash table chain + @return w->state() */ + inline uint32_t watch_remove(buf_page_t *w, hash_chain &chain); /** @return whether less than 1/4 of the buffer pool is available */ + TPOOL_SUPPRESS_TSAN bool running_out() const { return !recv_recovery_is_on() && - UNIV_UNLIKELY(UT_LIST_GET_LEN(free) + UT_LIST_GET_LEN(LRU) < - std::min(curr_size, old_size) / 4); + UT_LIST_GET_LEN(free) + UT_LIST_GET_LEN(LRU) < + n_chunks_new / 4 * chunks->size; + } + + /** @return whether the buffer pool has run out */ + TPOOL_SUPPRESS_TSAN + bool ran_out() const + { return UNIV_UNLIKELY(!try_LRU_scan || !UT_LIST_GET_LEN(free)); } + + /** @return whether the buffer pool is shrinking */ + inline bool is_shrinking() const + { + return n_chunks_new < n_chunks; } #ifdef UNIV_DEBUG @@ -1783,18 +1539,11 @@ public: static constexpr uint32_t READ_AHEAD_PAGES= 64; /** Buffer pool mutex */ - MY_ALIGNED(CPU_LEVEL1_DCACHE_LINESIZE) mysql_mutex_t mutex; - /** Number of pending LRU flush; protected by mutex. */ - ulint n_flush_LRU_; - /** broadcast when n_flush_LRU reaches 0; protected by mutex */ - pthread_cond_t done_flush_LRU; - /** Number of pending flush_list flush; protected by mutex */ - ulint n_flush_list_; - /** broadcast when n_flush_list reaches 0; protected by mutex */ - pthread_cond_t done_flush_list; - - TPOOL_SUPPRESS_TSAN ulint n_flush_LRU() const { return n_flush_LRU_; } - TPOOL_SUPPRESS_TSAN ulint n_flush_list() const { return n_flush_list_; } + alignas(CPU_LEVEL1_DCACHE_LINESIZE) mysql_mutex_t mutex; + /** current statistics; protected by mutex */ + buf_pool_stat_t stat; + /** old statistics; protected by mutex */ + buf_pool_stat_t old_stat; /** @name General fields */ /* @{ */ @@ -1809,30 +1558,35 @@ public: ut_allocator<unsigned char> allocator; /*!< Allocator used for allocating memory for the the "chunks" member. */ - volatile ulint n_chunks; /*!< number of buffer pool chunks */ - volatile ulint n_chunks_new; /*!< new number of buffer pool chunks */ + ulint n_chunks; /*!< number of buffer pool chunks */ + ulint n_chunks_new; /*!< new number of buffer pool chunks. + both n_chunks{,new} are protected under + mutex */ chunk_t* chunks; /*!< buffer pool chunks */ chunk_t* chunks_old; /*!< old buffer pool chunks to be freed after resizing buffer pool */ /** current pool size in pages */ Atomic_counter<ulint> curr_size; - /** previous pool size in pages */ - Atomic_counter<ulint> old_size; /** read-ahead request size in pages */ Atomic_counter<uint32_t> read_ahead_area; - /** Hash table with singly-linked overflow lists. @see hash_table_t */ + /** Hash table with singly-linked overflow lists */ struct page_hash_table { + static_assert(CPU_LEVEL1_DCACHE_LINESIZE >= 64, "less than 64 bytes"); + static_assert(!(CPU_LEVEL1_DCACHE_LINESIZE & 63), + "not a multiple of 64 bytes"); + /** Number of array[] elements per page_hash_latch. Must be one less than a power of 2. */ - static constexpr size_t ELEMENTS_PER_LATCH= CPU_LEVEL1_DCACHE_LINESIZE / - sizeof(void*) - 1; + static constexpr size_t ELEMENTS_PER_LATCH= 64 / sizeof(void*) - 1; + static constexpr size_t EMPTY_SLOTS_PER_LATCH= + ((CPU_LEVEL1_DCACHE_LINESIZE / 64) - 1) * (64 / sizeof(void*)); /** number of payload elements in array[] */ Atomic_relaxed<ulint> n_cells; /** the hash table, with pad(n_cells) elements, aligned to L1 cache size */ - hash_cell_t *array; + hash_chain *array; /** Create the hash table. @param n the lower bound of n_cells */ @@ -1844,7 +1598,12 @@ public: /** @return the index of an array element */ ulint calc_hash(ulint fold) const { return calc_hash(fold, n_cells); } /** @return raw array index converted to padded index */ - static ulint pad(ulint h) { return 1 + (h / ELEMENTS_PER_LATCH) + h; } + static ulint pad(ulint h) + { + ulint latches= h / ELEMENTS_PER_LATCH; + ulint empty_slots= latches * EMPTY_SLOTS_PER_LATCH; + return 1 + latches + empty_slots + h; + } private: /** @return the hash value before any ELEMENTS_PER_LATCH padding */ static ulint hash(ulint fold, ulint n) { return ut_hash_ulint(fold, n); } @@ -1854,29 +1613,72 @@ public: { return pad(hash(fold, n_cells)); } - /** Get a page_hash latch. */ - page_hash_latch *lock_get(ulint fold, ulint n) const + public: + /** @return the latch covering a hash table chain */ + static page_hash_latch &lock_get(hash_chain &chain) { static_assert(!((ELEMENTS_PER_LATCH + 1) & ELEMENTS_PER_LATCH), "must be one less than a power of 2"); - return reinterpret_cast<page_hash_latch*> - (&array[calc_hash(fold, n) & ~ELEMENTS_PER_LATCH]); + const size_t addr= reinterpret_cast<size_t>(&chain); + ut_ad(addr & (ELEMENTS_PER_LATCH * sizeof chain)); + return *reinterpret_cast<page_hash_latch*> + (addr & ~(ELEMENTS_PER_LATCH * sizeof chain)); } - public: - /** Get a page_hash latch. */ - page_hash_latch *lock_get(ulint fold) const - { return lock_get(fold, n_cells); } - - /** Acquire an array latch. - @tparam exclusive whether the latch is to be acquired exclusively - @param fold hash bucket key */ - template<bool exclusive> page_hash_latch *lock(ulint fold) + + /** Get a hash table slot. */ + hash_chain &cell_get(ulint fold) const + { return array[calc_hash(fold, n_cells)]; } + + /** Append a block descriptor to a hash bucket chain. */ + void append(hash_chain &chain, buf_page_t *bpage) + { + ut_ad(!bpage->in_page_hash); + ut_ad(!bpage->hash); + ut_d(bpage->in_page_hash= true); + buf_page_t **prev= &chain.first; + while (*prev) + { + ut_ad((*prev)->in_page_hash); + prev= &(*prev)->hash; + } + *prev= bpage; + } + + /** Remove a block descriptor from a hash bucket chain. */ + void remove(hash_chain &chain, buf_page_t *bpage) { - page_hash_latch *latch= lock_get(fold, n_cells); - latch->acquire<exclusive>(); - return latch; + ut_ad(bpage->in_page_hash); + buf_page_t **prev= &chain.first; + while (*prev != bpage) + { + ut_ad((*prev)->in_page_hash); + prev= &(*prev)->hash; + } + *prev= bpage->hash; + ut_d(bpage->in_page_hash= false); + bpage->hash= nullptr; } + /** Replace a block descriptor with another. */ + void replace(hash_chain &chain, buf_page_t *old, buf_page_t *bpage) + { + ut_ad(old->in_page_hash); + ut_ad(bpage->in_page_hash); + ut_d(old->in_page_hash= false); + ut_ad(bpage->hash == old->hash); + old->hash= nullptr; + buf_page_t **prev= &chain.first; + while (*prev != old) + { + ut_ad((*prev)->in_page_hash); + prev= &(*prev)->hash; + } + *prev= bpage; + } + + /** Look up a page in a hash bucket chain. */ + inline buf_page_t *get(const page_id_t id, const hash_chain &chain) const; + /** Exclusively aqcuire all latches */ inline void write_lock_all(); @@ -1891,8 +1693,6 @@ public: /** map of block->frame to buf_block_t blocks that belong to buf_buddy_alloc(); protected by buf_pool.mutex */ hash_table_t zip_hash; - /** number of pending read operations */ - Atomic_counter<ulint> n_pend_reads; Atomic_counter<ulint> n_pend_unzip; /*!< number of pending decompressions */ @@ -1902,44 +1702,90 @@ public: buf_buddy_stat_t buddy_stat[BUF_BUDDY_SIZES_MAX + 1]; /*!< Statistics of buddy system, indexed by block size */ - buf_pool_stat_t stat; /*!< current statistics */ - buf_pool_stat_t old_stat; /*!< old statistics */ /* @} */ + /** number of index page splits */ + Atomic_counter<ulint> pages_split; + /** @name Page flushing algorithm fields */ /* @{ */ /** mutex protecting flush_list, buf_page_t::set_oldest_modification() and buf_page_t::list pointers when !oldest_modification() */ - MY_ALIGNED(CPU_LEVEL1_DCACHE_LINESIZE) mysql_mutex_t flush_list_mutex; + alignas(CPU_LEVEL1_DCACHE_LINESIZE) mysql_mutex_t flush_list_mutex; /** "hazard pointer" for flush_list scans; protected by flush_list_mutex */ FlushHp flush_hp; - /** modified blocks (a subset of LRU) */ + /** flush_list size in bytes; protected by flush_list_mutex */ + ulint flush_list_bytes; + /** possibly modified persistent pages (a subset of LRU); + os_aio_pending_writes() is approximately COUNT(is_write_fixed()) */ UT_LIST_BASE_NODE_T(buf_page_t) flush_list; private: - /** whether the page cleaner needs wakeup from indefinite sleep */ - bool page_cleaner_is_idle; + static constexpr unsigned PAGE_CLEANER_IDLE= 1; + static constexpr unsigned FLUSH_LIST_ACTIVE= 2; + static constexpr unsigned LRU_FLUSH= 4; + + /** Number of pending LRU flush * LRU_FLUSH + + PAGE_CLEANER_IDLE + FLUSH_LIST_ACTIVE flags */ + unsigned page_cleaner_status; /** track server activity count for signaling idle flushing */ ulint last_activity_count; public: /** signalled to wake up the page_cleaner; protected by flush_list_mutex */ pthread_cond_t do_flush_list; + /** broadcast when !n_flush(); protected by flush_list_mutex */ + pthread_cond_t done_flush_LRU; + /** broadcast when a batch completes; protected by flush_list_mutex */ + pthread_cond_t done_flush_list; + + /** @return number of pending LRU flush */ + unsigned n_flush() const + { + mysql_mutex_assert_owner(&flush_list_mutex); + return page_cleaner_status / LRU_FLUSH; + } + + /** Increment the number of pending LRU flush */ + inline void n_flush_inc(); + + /** Decrement the number of pending LRU flush */ + inline void n_flush_dec(); + + /** @return whether flush_list flushing is active */ + bool flush_list_active() const + { + mysql_mutex_assert_owner(&flush_list_mutex); + return page_cleaner_status & FLUSH_LIST_ACTIVE; + } + + void flush_list_set_active() + { + ut_ad(!flush_list_active()); + page_cleaner_status+= FLUSH_LIST_ACTIVE; + } + void flush_list_set_inactive() + { + ut_ad(flush_list_active()); + page_cleaner_status-= FLUSH_LIST_ACTIVE; + } /** @return whether the page cleaner must sleep due to being idle */ bool page_cleaner_idle() const { mysql_mutex_assert_owner(&flush_list_mutex); - return page_cleaner_is_idle; + return page_cleaner_status & PAGE_CLEANER_IDLE; } - /** Wake up the page cleaner if needed */ - void page_cleaner_wakeup(); + /** Wake up the page cleaner if needed. + @param for_LRU whether to wake up for LRU eviction */ + void page_cleaner_wakeup(bool for_LRU= false); /** Register whether an explicit wakeup of the page cleaner is needed */ void page_cleaner_set_idle(bool deep_sleep) { mysql_mutex_assert_owner(&flush_list_mutex); - page_cleaner_is_idle= deep_sleep; + page_cleaner_status= (page_cleaner_status & ~PAGE_CLEANER_IDLE) | + (PAGE_CLEANER_IDLE * deep_sleep); } /** Update server last activity count */ @@ -1949,9 +1795,6 @@ public: last_activity_count= activity_count; } - // n_flush_LRU() + n_flush_list() - // is approximately COUNT(io_fix()==BUF_IO_WRITE) in flush_list - unsigned freed_page_clock;/*!< a sequence number used to count the number of buffer blocks removed from the end of @@ -1961,16 +1804,10 @@ public: to read this for heuristic purposes without holding any mutex or latch */ - bool try_LRU_scan; /*!< Cleared when an LRU - scan for free block fails. This - flag is used to avoid repeated - scans of LRU list when we know - that there is no free block - available in the scan depth for - eviction. Set whenever - we flush a batch from the - buffer pool. Protected by the - buf_pool.mutex */ + /** Cleared when buf_LRU_get_free_block() fails. + Set whenever the free list grows, along with a broadcast of done_free. + Protected by buf_pool.mutex. */ + Atomic_relaxed<bool> try_LRU_scan; /* @} */ /** @name LRU replacement algorithm fields */ @@ -1979,7 +1816,8 @@ public: UT_LIST_BASE_NODE_T(buf_page_t) free; /*!< base node of the free block list */ - /** signaled each time when the free list grows; protected by mutex */ + /** broadcast each time when the free list grows or try_LRU_scan is set; + protected by mutex */ pthread_cond_t done_free; UT_LIST_BASE_NODE_T(buf_page_t) withdraw; @@ -2034,34 +1872,13 @@ public: /** Reserve a buffer. */ buf_tmp_buffer_t *io_buf_reserve() { return io_buf.reserve(); } - /** @return whether any I/O is pending */ - bool any_io_pending() - { - if (n_pend_reads) - return true; - mysql_mutex_lock(&mutex); - const bool any_pending{n_flush_LRU_ || n_flush_list_}; - mysql_mutex_unlock(&mutex); - return any_pending; - } - /** @return total amount of pending I/O */ - ulint io_pending() const - { - return n_pend_reads + n_flush_LRU() + n_flush_list(); - } - private: /** Remove a block from the flush list. */ inline void delete_from_flush_list_low(buf_page_t *bpage); - /** Remove a block from flush_list. - @param bpage buffer pool page - @param clear whether to invoke buf_page_t::clear_oldest_modification() */ - void delete_from_flush_list(buf_page_t *bpage, bool clear); public: /** Remove a block from flush_list. @param bpage buffer pool page */ - void delete_from_flush_list(buf_page_t *bpage) - { delete_from_flush_list(bpage, true); } + void delete_from_flush_list(buf_page_t *bpage); /** Insert a modified block into the flush list. @param block modified block @@ -2069,7 +1886,7 @@ public: void insert_into_flush_list(buf_block_t *block, lsn_t lsn); /** Free a page whose underlying file page has been freed. */ - inline void release_freed_page(buf_page_t *bpage); + ATTRIBUTE_COLD void release_freed_page(buf_page_t *bpage); private: /** Temporary memory for page_compressed and encrypted I/O */ @@ -2080,34 +1897,12 @@ private: /** array of slots */ buf_tmp_buffer_t *slots; - void create(ulint n_slots) - { - this->n_slots= n_slots; - slots= static_cast<buf_tmp_buffer_t*> - (ut_malloc_nokey(n_slots * sizeof *slots)); - memset((void*) slots, 0, n_slots * sizeof *slots); - } + void create(ulint n_slots); - void close() - { - for (buf_tmp_buffer_t *s= slots, *e= slots + n_slots; s != e; s++) - { - aligned_free(s->crypt_buf); - aligned_free(s->comp_buf); - } - ut_free(slots); - slots= nullptr; - n_slots= 0; - } + void close(); /** Reserve a buffer */ - buf_tmp_buffer_t *reserve() - { - for (buf_tmp_buffer_t *s= slots, *e= slots + n_slots; s != e; s++) - if (s->acquire()) - return s; - return nullptr; - } + buf_tmp_buffer_t *reserve(); } io_buf; /** whether resize() is in the critical path */ @@ -2117,64 +1912,46 @@ private: /** The InnoDB buffer pool */ extern buf_pool_t buf_pool; -inline void page_hash_latch::read_lock() +inline buf_page_t *buf_pool_t::page_hash_table::get(const page_id_t id, + const hash_chain &chain) + const +{ +#ifdef SAFE_MUTEX + DBUG_ASSERT(mysql_mutex_is_owner(&buf_pool.mutex) || + lock_get(const_cast<hash_chain&>(chain)).is_locked()); +#endif /* SAFE_MUTEX */ + for (buf_page_t *bpage= chain.first; bpage; bpage= bpage->hash) + { + ut_ad(bpage->in_page_hash); + ut_ad(bpage->in_file()); + if (bpage->id() == id) + return bpage; + } + return nullptr; +} + +#ifdef SUX_LOCK_GENERIC +inline void page_hash_latch::lock_shared() { mysql_mutex_assert_not_owner(&buf_pool.mutex); if (!read_trylock()) read_lock_wait(); } -inline void page_hash_latch::write_lock() +inline void page_hash_latch::lock() { if (!write_trylock()) write_lock_wait(); } +#endif /* SUX_LOCK_GENERIC */ -inline void buf_page_t::add_buf_fix_count(uint32_t count) -{ - mysql_mutex_assert_owner(&buf_pool.mutex); - buf_fix_count_+= count; -} - -inline void buf_page_t::set_buf_fix_count(uint32_t count) -{ - mysql_mutex_assert_owner(&buf_pool.mutex); - buf_fix_count_= count; -} - -inline void buf_page_t::set_state(buf_page_state state) -{ - mysql_mutex_assert_owner(&buf_pool.mutex); -#ifdef UNIV_DEBUG - switch (state) { - case BUF_BLOCK_REMOVE_HASH: - /* buf_pool_t::corrupted_evict() invokes set_corrupt_id() - before buf_LRU_free_one_page(), so we cannot assert that - we are holding the hash_lock. */ - break; - case BUF_BLOCK_MEMORY: - if (!in_file()) break; - /* fall through */ - case BUF_BLOCK_FILE_PAGE: - ut_ad(buf_pool.hash_lock_get(id_)->is_write_locked()); - break; - case BUF_BLOCK_NOT_USED: - if (!in_file()) break; - /* fall through */ - case BUF_BLOCK_ZIP_PAGE: - ut_ad(buf_pool.hash_lock_get(id_)->is_write_locked() || - (this >= &buf_pool.watch[0] && - this <= &buf_pool.watch[UT_ARR_SIZE(buf_pool.watch)])); - break; - } -#endif - state_= state; -} - -inline void buf_page_t::set_io_fix(buf_io_fix io_fix) +inline void buf_page_t::set_state(uint32_t s) { mysql_mutex_assert_owner(&buf_pool.mutex); - io_fix_= io_fix; + ut_ad(s <= REMOVE_HASH || s >= UNFIXED); + ut_ad(s < WRITE_FIX); + ut_ad(s <= READ_FIX || zip.fix == READ_FIX); + zip.fix= s; } inline void buf_page_t::set_corrupt_id() @@ -2191,19 +1968,15 @@ inline void buf_page_t::set_corrupt_id() default: ut_ad("block is dirty" == 0); } - switch (state()) { - case BUF_BLOCK_REMOVE_HASH: - break; - case BUF_BLOCK_ZIP_PAGE: - case BUF_BLOCK_FILE_PAGE: - ut_ad(buf_pool.hash_lock_get(id_)->is_write_locked()); - break; - case BUF_BLOCK_NOT_USED: - case BUF_BLOCK_MEMORY: - ut_ad("invalid state" == 0); + const auto f= state(); + if (f != REMOVE_HASH) + { + ut_ad(f >= UNFIXED); + ut_ad(buf_pool.page_hash.lock_get(buf_pool.page_hash.cell_get(id_.fold())). + is_write_locked()); } #endif - id_= page_id_t(~0ULL); + id_.set_corrupted(); } /** Set oldest_modification when adding to buf_pool.flush_list */ @@ -2218,10 +1991,12 @@ inline void buf_page_t::set_oldest_modification(lsn_t lsn) /** Clear oldest_modification after removing from buf_pool.flush_list */ inline void buf_page_t::clear_oldest_modification() { - mysql_mutex_assert_owner(&buf_pool.flush_list_mutex); - ut_d(const auto state= state_); - ut_ad(state == BUF_BLOCK_FILE_PAGE || state == BUF_BLOCK_ZIP_PAGE || - state == BUF_BLOCK_REMOVE_HASH); +#ifdef SAFE_MUTEX + if (oldest_modification() != 2) + mysql_mutex_assert_owner(&buf_pool.flush_list_mutex); +#endif /* SAFE_MUTEX */ + ut_d(const auto s= state()); + ut_ad(s >= REMOVE_HASH); ut_ad(oldest_modification()); ut_ad(!list.prev); ut_ad(!list.next); @@ -2231,46 +2006,16 @@ inline void buf_page_t::clear_oldest_modification() oldest_modification_.store(0, std::memory_order_release); } -/** Note that a block is no longer dirty, while not removing -it from buf_pool.flush_list */ -inline void buf_page_t::clear_oldest_modification(bool temporary) -{ - ut_ad(temporary == fsp_is_system_temporary(id().space())); - if (temporary) - { - ut_ad(oldest_modification() == 2); - oldest_modification_= 0; - } - else - { - /* We use release memory order to guarantee that callers of - oldest_modification_acquire() will observe the block as - being detached from buf_pool.flush_list, after reading the value 0. */ - ut_ad(oldest_modification() > 2); - oldest_modification_.store(1, std::memory_order_release); - } -} - -/** @return whether the block is modified and ready for flushing */ -inline bool buf_page_t::ready_for_flush() const -{ - mysql_mutex_assert_owner(&buf_pool.mutex); - ut_ad(in_LRU_list); - ut_a(in_file()); - ut_ad(fsp_is_system_temporary(id().space()) - ? oldest_modification() == 2 - : oldest_modification() > 2); - return io_fix_ == BUF_IO_NONE; -} - /** @return whether the block can be relocated in memory. The block can be dirty, but it must not be I/O-fixed or bufferfixed. */ inline bool buf_page_t::can_relocate() const { mysql_mutex_assert_owner(&buf_pool.mutex); - ut_ad(in_file()); + const auto f= state(); + ut_ad(f >= FREED); ut_ad(in_LRU_list); - return io_fix_ == BUF_IO_NONE && !buf_fix_count_; + return (f == FREED || (f < READ_FIX && !(f & ~LRU_MASK))) && + !lock.is_locked_or_waiting(); } /** @return whether the block has been flagged old in buf_pool.LRU */ @@ -2331,41 +2076,26 @@ inline void buf_page_t::set_old(bool old) /********************************************************************** Let us list the consistency conditions for different control block states. -NOT_USED: is in free list, not in LRU list, not in flush list, nor - page hash table -MEMORY: is not in free list, LRU list, or flush list, nor page - hash table -FILE_PAGE: space and offset are defined, is in page hash table - if io_fix == BUF_IO_WRITE, - buf_pool.n_flush_LRU() || buf_pool.n_flush_list() - - (1) if buf_fix_count == 0, then - is in LRU list, not in free list - is in flush list, - if and only if oldest_modification > 0 - is x-locked, - if and only if io_fix == BUF_IO_READ - is s-locked, - if and only if io_fix == BUF_IO_WRITE - - (2) if buf_fix_count > 0, then - is not in LRU list, not in free list - is in flush list, - if and only if oldest_modification > 0 - if io_fix == BUF_IO_READ, - is x-locked - if io_fix == BUF_IO_WRITE, - is s-locked +NOT_USED: is in free list, not LRU, not flush_list, nor page_hash +MEMORY: is not in any of free, LRU, flush_list, page_hash +in_file(): is not in free list, is in LRU list, id() is defined, + is in page_hash (not necessarily if is_read_fixed()) + + is in buf_pool.flush_list, if and only + if oldest_modification == 1 || oldest_modification > 2 + + (1) if is_write_fixed(): is u-locked + (2) if is_read_fixed(): is x-locked State transitions: NOT_USED => MEMORY -MEMORY => FILE_PAGE MEMORY => NOT_USED -FILE_PAGE => NOT_USED NOTE: This transition is allowed if and only if - (1) buf_fix_count == 0, - (2) oldest_modification == 0, and - (3) io_fix == 0. +MEMORY => UNFIXED +UNFIXED => in_file() +in_file() => UNFIXED or FREED +UNFIXED or FREED => REMOVE_HASH +REMOVE_HASH => NOT_USED (if and only if !oldest_modification()) */ /** Select from where to start a scan. If we have scanned @@ -2427,5 +2157,3 @@ struct CheckUnzipLRUAndLRUList { #include "buf0buf.inl" #endif /* !UNIV_INNOCHECKSUM */ - -#endif |