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982 lines
28 KiB
C
982 lines
28 KiB
C
/*****************************************************************************
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Copyright (c) 1995, 2010, Innobase Oy. All Rights Reserved.
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This program is free software; you can redistribute it and/or modify it under
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the terms of the GNU General Public License as published by the Free Software
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Foundation; version 2 of the License.
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This program is distributed in the hope that it will be useful, but WITHOUT
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ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
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FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
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You should have received a copy of the GNU General Public License along with
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this program; if not, write to the Free Software Foundation, Inc.,
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51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
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*****************************************************************************/
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/**************************************************//**
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@file buf/buf0rea.c
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The database buffer read
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Created 11/5/1995 Heikki Tuuri
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*******************************************************/
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#include "buf0rea.h"
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#include "fil0fil.h"
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#include "mtr0mtr.h"
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#include "buf0buf.h"
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#include "buf0flu.h"
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#include "buf0lru.h"
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#include "ibuf0ibuf.h"
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#include "log0recv.h"
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#include "trx0sys.h"
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#include "os0file.h"
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#include "srv0start.h"
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#include "srv0srv.h"
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#include "mysql/plugin.h"
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#include "mysql/service_thd_wait.h"
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/** There must be at least this many pages in buf_pool in the area to start
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a random read-ahead */
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#define BUF_READ_AHEAD_RANDOM_THRESHOLD(b) \
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(5 + BUF_READ_AHEAD_AREA(b) / 8)
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/** If there are buf_pool->curr_size per the number below pending reads, then
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read-ahead is not done: this is to prevent flooding the buffer pool with
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i/o-fixed buffer blocks */
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#define BUF_READ_AHEAD_PEND_LIMIT 2
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/********************************************************************//**
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Unfixes the pages, unlatches the page,
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removes it from page_hash and removes it from LRU. */
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static
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void
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buf_read_page_handle_error(
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/*=======================*/
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buf_page_t* bpage) /*!< in: pointer to the block */
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{
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buf_pool_t* buf_pool = buf_pool_from_bpage(bpage);
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const ibool uncompressed = (buf_page_get_state(bpage)
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== BUF_BLOCK_FILE_PAGE);
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/* First unfix and release lock on the bpage */
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mutex_enter(&buf_pool->LRU_list_mutex);
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mutex_enter(buf_page_get_mutex(bpage));
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ut_ad(buf_page_get_io_fix(bpage) == BUF_IO_READ);
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ut_ad(bpage->buf_fix_count == 0);
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/* Set BUF_IO_NONE before we remove the block from LRU list */
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buf_page_set_io_fix(bpage, BUF_IO_NONE);
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if (uncompressed) {
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rw_lock_x_unlock_gen(
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&((buf_block_t*) bpage)->lock,
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BUF_IO_READ);
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}
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/* remove the block from LRU list */
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buf_LRU_free_one_page(bpage);
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ut_ad(buf_pool->n_pend_reads > 0);
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buf_pool->n_pend_reads--;
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mutex_exit(buf_page_get_mutex(bpage));
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mutex_exit(&buf_pool->LRU_list_mutex);
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}
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/********************************************************************//**
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Low-level function which reads a page asynchronously from a file to the
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buffer buf_pool if it is not already there, in which case does nothing.
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Sets the io_fix flag and sets an exclusive lock on the buffer frame. The
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flag is cleared and the x-lock released by an i/o-handler thread.
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@return 1 if a read request was queued, 0 if the page already resided
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in buf_pool, or if the page is in the doublewrite buffer blocks in
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which case it is never read into the pool, or if the tablespace does
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not exist or is being dropped
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@return 1 if read request is issued. 0 if it is not */
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UNIV_INTERN
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ulint
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buf_read_page_low(
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/*==============*/
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ulint* err, /*!< out: DB_SUCCESS or DB_TABLESPACE_DELETED if we are
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trying to read from a non-existent tablespace, or a
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tablespace which is just now being dropped */
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ibool sync, /*!< in: TRUE if synchronous aio is desired */
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ulint mode, /*!< in: BUF_READ_IBUF_PAGES_ONLY, ...,
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ORed to OS_AIO_SIMULATED_WAKE_LATER (see below
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at read-ahead functions) */
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ulint space, /*!< in: space id */
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ulint zip_size,/*!< in: compressed page size, or 0 */
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ibool unzip, /*!< in: TRUE=request uncompressed page */
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ib_int64_t tablespace_version, /*!< in: if the space memory object has
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this timestamp different from what we are giving here,
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treat the tablespace as dropped; this is a timestamp we
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use to stop dangling page reads from a tablespace
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which we have DISCARDed + IMPORTed back */
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ulint offset, /*!< in: page number */
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trx_t* trx)
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{
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buf_page_t* bpage;
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ulint wake_later;
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*err = DB_SUCCESS;
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wake_later = mode & OS_AIO_SIMULATED_WAKE_LATER;
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mode = mode & ~OS_AIO_SIMULATED_WAKE_LATER;
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if (trx_doublewrite
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&& (space == TRX_SYS_SPACE
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|| (srv_doublewrite_file && space == TRX_DOUBLEWRITE_SPACE))
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&& ( (offset >= trx_doublewrite->block1
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&& offset < trx_doublewrite->block1
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+ TRX_SYS_DOUBLEWRITE_BLOCK_SIZE)
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|| (offset >= trx_doublewrite->block2
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&& offset < trx_doublewrite->block2
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+ TRX_SYS_DOUBLEWRITE_BLOCK_SIZE))) {
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ut_print_timestamp(stderr);
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fprintf(stderr,
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" InnoDB: Warning: trying to read"
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" doublewrite buffer page %lu\n",
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(ulong) offset);
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return(0);
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}
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if (ibuf_bitmap_page(zip_size, offset)
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|| trx_sys_hdr_page(space, offset)) {
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/* Trx sys header is so low in the latching order that we play
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safe and do not leave the i/o-completion to an asynchronous
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i/o-thread. Ibuf bitmap pages must always be read with
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syncronous i/o, to make sure they do not get involved in
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thread deadlocks. */
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sync = TRUE;
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}
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/* The following call will also check if the tablespace does not exist
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or is being dropped; if we succeed in initing the page in the buffer
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pool for read, then DISCARD cannot proceed until the read has
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completed */
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bpage = buf_page_init_for_read(err, mode, space, zip_size, unzip,
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tablespace_version, offset);
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if (bpage == NULL) {
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/* bugfix: http://bugs.mysql.com/bug.php?id=43948 */
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if (recv_recovery_is_on() && *err == DB_TABLESPACE_DELETED) {
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/* hashed log recs must be treated here */
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recv_addr_t* recv_addr;
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mutex_enter(&(recv_sys->mutex));
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if (recv_sys->apply_log_recs == FALSE) {
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mutex_exit(&(recv_sys->mutex));
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goto not_to_recover;
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}
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/* recv_get_fil_addr_struct() */
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recv_addr = HASH_GET_FIRST(recv_sys->addr_hash,
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hash_calc_hash(ut_fold_ulint_pair(space, offset),
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recv_sys->addr_hash));
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while (recv_addr) {
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if ((recv_addr->space == space)
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&& (recv_addr->page_no == offset)) {
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break;
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}
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recv_addr = HASH_GET_NEXT(addr_hash, recv_addr);
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}
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if ((recv_addr == NULL)
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|| (recv_addr->state == RECV_BEING_PROCESSED)
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|| (recv_addr->state == RECV_PROCESSED)) {
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mutex_exit(&(recv_sys->mutex));
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goto not_to_recover;
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}
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fprintf(stderr, " (cannot find space: %lu)", space);
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recv_addr->state = RECV_PROCESSED;
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ut_a(recv_sys->n_addrs);
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recv_sys->n_addrs--;
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mutex_exit(&(recv_sys->mutex));
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}
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not_to_recover:
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return(0);
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}
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#ifdef UNIV_DEBUG
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if (buf_debug_prints) {
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fprintf(stderr,
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"Posting read request for page %lu, sync %lu\n",
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(ulong) offset,
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(ulong) sync);
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}
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#endif
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ut_ad(buf_page_in_file(bpage));
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if (sync) {
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thd_wait_begin(NULL, THD_WAIT_DISKIO);
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}
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if (zip_size) {
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*err = _fil_io(OS_FILE_READ | wake_later,
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sync, space, zip_size, offset, 0, zip_size,
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bpage->zip.data, bpage, trx);
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} else {
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ut_a(buf_page_get_state(bpage) == BUF_BLOCK_FILE_PAGE);
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*err = _fil_io(OS_FILE_READ | wake_later,
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sync, space, 0, offset, 0, UNIV_PAGE_SIZE,
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((buf_block_t*) bpage)->frame, bpage, trx);
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}
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if (sync) {
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thd_wait_end(NULL);
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}
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if (*err == DB_TABLESPACE_DELETED) {
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buf_read_page_handle_error(bpage);
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return(0);
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}
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SRV_CORRUPT_TABLE_CHECK(*err == DB_SUCCESS, bpage->is_corrupt = TRUE;);
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if (sync) {
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/* The i/o is already completed when we arrive from
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fil_read */
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if (!buf_page_io_complete(bpage)) {
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return(0);
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}
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}
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return(1);
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}
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/********************************************************************//**
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Applies a random read-ahead in buf_pool if there are at least a threshold
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value of accessed pages from the random read-ahead area. Does not read any
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page, not even the one at the position (space, offset), if the read-ahead
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mechanism is not activated. NOTE 1: the calling thread may own latches on
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pages: to avoid deadlocks this function must be written such that it cannot
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end up waiting for these latches! NOTE 2: the calling thread must want
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access to the page given: this rule is set to prevent unintended read-aheads
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performed by ibuf routines, a situation which could result in a deadlock if
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the OS does not support asynchronous i/o.
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@return number of page read requests issued; NOTE that if we read ibuf
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pages, it may happen that the page at the given page number does not
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get read even if we return a positive value!
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@return number of page read requests issued */
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UNIV_INTERN
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ulint
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buf_read_ahead_random(
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/*==================*/
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ulint space, /*!< in: space id */
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ulint zip_size, /*!< in: compressed page size in bytes,
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or 0 */
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ulint offset, /*!< in: page number of a page which
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the current thread wants to access */
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ibool inside_ibuf, /*!< in: TRUE if we are inside ibuf
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routine */
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trx_t* trx)
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{
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buf_pool_t* buf_pool = buf_pool_get(space, offset);
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ib_int64_t tablespace_version;
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ulint recent_blocks = 0;
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ulint ibuf_mode;
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ulint count;
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ulint low, high;
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ulint err;
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ulint i;
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const ulint buf_read_ahead_random_area
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= BUF_READ_AHEAD_AREA(buf_pool);
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if (!srv_random_read_ahead) {
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/* Disabled by user */
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return(0);
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}
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if (srv_startup_is_before_trx_rollback_phase) {
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/* No read-ahead to avoid thread deadlocks */
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return(0);
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}
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if (ibuf_bitmap_page(zip_size, offset)
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|| trx_sys_hdr_page(space, offset)) {
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/* If it is an ibuf bitmap page or trx sys hdr, we do
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no read-ahead, as that could break the ibuf page access
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order */
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return(0);
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}
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/* Remember the tablespace version before we ask te tablespace size
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below: if DISCARD + IMPORT changes the actual .ibd file meanwhile, we
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do not try to read outside the bounds of the tablespace! */
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tablespace_version = fil_space_get_version(space);
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low = (offset / buf_read_ahead_random_area)
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* buf_read_ahead_random_area;
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high = (offset / buf_read_ahead_random_area + 1)
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* buf_read_ahead_random_area;
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if (high > fil_space_get_size(space)) {
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high = fil_space_get_size(space);
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}
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buf_pool_mutex_enter(buf_pool);
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if (buf_pool->n_pend_reads
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> buf_pool->curr_size / BUF_READ_AHEAD_PEND_LIMIT) {
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buf_pool_mutex_exit(buf_pool);
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return(0);
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}
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/* Count how many blocks in the area have been recently accessed,
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that is, reside near the start of the LRU list. */
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for (i = low; i < high; i++) {
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const buf_page_t* bpage =
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buf_page_hash_get(buf_pool, space, i);
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if (bpage
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&& buf_page_is_accessed(bpage)
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&& buf_page_peek_if_young(bpage)) {
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recent_blocks++;
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if (recent_blocks
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>= BUF_READ_AHEAD_RANDOM_THRESHOLD(buf_pool)) {
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buf_pool_mutex_exit(buf_pool);
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goto read_ahead;
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}
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}
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}
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buf_pool_mutex_exit(buf_pool);
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/* Do nothing */
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return(0);
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read_ahead:
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/* Read all the suitable blocks within the area */
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if (inside_ibuf) {
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ibuf_mode = BUF_READ_IBUF_PAGES_ONLY;
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} else {
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ibuf_mode = BUF_READ_ANY_PAGE;
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}
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count = 0;
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for (i = low; i < high; i++) {
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/* It is only sensible to do read-ahead in the non-sync aio
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mode: hence FALSE as the first parameter */
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if (!ibuf_bitmap_page(zip_size, i)) {
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count += buf_read_page_low(
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&err, FALSE,
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ibuf_mode | OS_AIO_SIMULATED_WAKE_LATER,
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space, zip_size, FALSE,
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tablespace_version, i, trx);
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if (err == DB_TABLESPACE_DELETED) {
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ut_print_timestamp(stderr);
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fprintf(stderr,
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" InnoDB: Warning: in random"
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" readahead trying to access\n"
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"InnoDB: tablespace %lu page %lu,\n"
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"InnoDB: but the tablespace does not"
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" exist or is just being dropped.\n",
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(ulong) space, (ulong) i);
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}
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}
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}
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|
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/* In simulated aio we wake the aio handler threads only after
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queuing all aio requests, in native aio the following call does
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nothing: */
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os_aio_simulated_wake_handler_threads();
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|
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#ifdef UNIV_DEBUG
|
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if (buf_debug_prints && (count > 0)) {
|
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fprintf(stderr,
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"Random read-ahead space %lu offset %lu pages %lu\n",
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(ulong) space, (ulong) offset,
|
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(ulong) count);
|
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}
|
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#endif /* UNIV_DEBUG */
|
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|
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/* Read ahead is considered one I/O operation for the purpose of
|
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LRU policy decision. */
|
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buf_LRU_stat_inc_io();
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|
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buf_pool->stat.n_ra_pages_read_rnd += count;
|
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srv_buf_pool_reads += count;
|
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return(count);
|
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}
|
|
|
|
/********************************************************************//**
|
|
High-level function which reads a page asynchronously from a file to the
|
|
buffer buf_pool if it is not already there. Sets the io_fix flag and sets
|
|
an exclusive lock on the buffer frame. The flag is cleared and the x-lock
|
|
released by the i/o-handler thread.
|
|
@return TRUE if page has been read in, FALSE in case of failure */
|
|
UNIV_INTERN
|
|
ibool
|
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buf_read_page(
|
|
/*==========*/
|
|
ulint space, /*!< in: space id */
|
|
ulint zip_size,/*!< in: compressed page size in bytes, or 0 */
|
|
ulint offset, /*!< in: page number */
|
|
trx_t* trx)
|
|
{
|
|
buf_pool_t* buf_pool = buf_pool_get(space, offset);
|
|
ib_int64_t tablespace_version;
|
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ulint count;
|
|
ulint err;
|
|
|
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tablespace_version = fil_space_get_version(space);
|
|
|
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/* We do the i/o in the synchronous aio mode to save thread
|
|
switches: hence TRUE */
|
|
|
|
count = buf_read_page_low(&err, TRUE, BUF_READ_ANY_PAGE, space,
|
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zip_size, FALSE,
|
|
tablespace_version, offset, trx);
|
|
srv_buf_pool_reads += count;
|
|
if (err == DB_TABLESPACE_DELETED) {
|
|
ut_print_timestamp(stderr);
|
|
fprintf(stderr,
|
|
" InnoDB: Error: trying to access"
|
|
" tablespace %lu page no. %lu,\n"
|
|
"InnoDB: but the tablespace does not exist"
|
|
" or is just being dropped.\n",
|
|
(ulong) space, (ulong) offset);
|
|
}
|
|
|
|
/* Flush pages from the end of the LRU list if necessary */
|
|
buf_flush_free_margin(buf_pool, TRUE);
|
|
|
|
/* Increment number of I/O operations used for LRU policy. */
|
|
buf_LRU_stat_inc_io();
|
|
|
|
return(count > 0);
|
|
}
|
|
|
|
/********************************************************************//**
|
|
Applies linear read-ahead if in the buf_pool the page is a border page of
|
|
a linear read-ahead area and all the pages in the area have been accessed.
|
|
Does not read any page if the read-ahead mechanism is not activated. Note
|
|
that the algorithm looks at the 'natural' adjacent successor and
|
|
predecessor of the page, which on the leaf level of a B-tree are the next
|
|
and previous page in the chain of leaves. To know these, the page specified
|
|
in (space, offset) must already be present in the buf_pool. Thus, the
|
|
natural way to use this function is to call it when a page in the buf_pool
|
|
is accessed the first time, calling this function just after it has been
|
|
bufferfixed.
|
|
NOTE 1: as this function looks at the natural predecessor and successor
|
|
fields on the page, what happens, if these are not initialized to any
|
|
sensible value? No problem, before applying read-ahead we check that the
|
|
area to read is within the span of the space, if not, read-ahead is not
|
|
applied. An uninitialized value may result in a useless read operation, but
|
|
only very improbably.
|
|
NOTE 2: the calling thread may own latches on pages: to avoid deadlocks this
|
|
function must be written such that it cannot end up waiting for these
|
|
latches!
|
|
NOTE 3: the calling thread must want access to the page given: this rule is
|
|
set to prevent unintended read-aheads performed by ibuf routines, a situation
|
|
which could result in a deadlock if the OS does not support asynchronous io.
|
|
@return number of page read requests issued */
|
|
UNIV_INTERN
|
|
ulint
|
|
buf_read_ahead_linear(
|
|
/*==================*/
|
|
ulint space, /*!< in: space id */
|
|
ulint zip_size, /*!< in: compressed page size in bytes, or 0 */
|
|
ulint offset, /*!< in: page number; see NOTE 3 above */
|
|
ibool inside_ibuf, /*!< in: TRUE if we are inside ibuf routine */
|
|
trx_t* trx)
|
|
{
|
|
buf_pool_t* buf_pool = buf_pool_get(space, offset);
|
|
ib_int64_t tablespace_version;
|
|
buf_page_t* bpage;
|
|
buf_frame_t* frame;
|
|
buf_page_t* pred_bpage = NULL;
|
|
ulint pred_offset;
|
|
ulint succ_offset;
|
|
ulint count;
|
|
int asc_or_desc;
|
|
ulint new_offset;
|
|
ulint fail_count;
|
|
ulint ibuf_mode;
|
|
ulint low, high;
|
|
ulint err;
|
|
ulint i;
|
|
const ulint buf_read_ahead_linear_area
|
|
= BUF_READ_AHEAD_AREA(buf_pool);
|
|
ulint threshold;
|
|
|
|
if (!(srv_read_ahead & 2)) {
|
|
return(0);
|
|
}
|
|
|
|
if (UNIV_UNLIKELY(srv_startup_is_before_trx_rollback_phase)) {
|
|
/* No read-ahead to avoid thread deadlocks */
|
|
return(0);
|
|
}
|
|
|
|
low = (offset / buf_read_ahead_linear_area)
|
|
* buf_read_ahead_linear_area;
|
|
high = (offset / buf_read_ahead_linear_area + 1)
|
|
* buf_read_ahead_linear_area;
|
|
|
|
if ((offset != low) && (offset != high - 1)) {
|
|
/* This is not a border page of the area: return */
|
|
|
|
return(0);
|
|
}
|
|
|
|
if (ibuf_bitmap_page(zip_size, offset)
|
|
|| trx_sys_hdr_page(space, offset)) {
|
|
|
|
/* If it is an ibuf bitmap page or trx sys hdr, we do
|
|
no read-ahead, as that could break the ibuf page access
|
|
order */
|
|
|
|
return(0);
|
|
}
|
|
|
|
/* Remember the tablespace version before we ask te tablespace size
|
|
below: if DISCARD + IMPORT changes the actual .ibd file meanwhile, we
|
|
do not try to read outside the bounds of the tablespace! */
|
|
|
|
tablespace_version = fil_space_get_version(space);
|
|
|
|
buf_pool_mutex_enter(buf_pool);
|
|
|
|
if (high > fil_space_get_size(space)) {
|
|
buf_pool_mutex_exit(buf_pool);
|
|
/* The area is not whole, return */
|
|
|
|
return(0);
|
|
}
|
|
|
|
if (buf_pool->n_pend_reads
|
|
> buf_pool->curr_size / BUF_READ_AHEAD_PEND_LIMIT) {
|
|
buf_pool_mutex_exit(buf_pool);
|
|
|
|
return(0);
|
|
}
|
|
buf_pool_mutex_exit(buf_pool);
|
|
|
|
/* Check that almost all pages in the area have been accessed; if
|
|
offset == low, the accesses must be in a descending order, otherwise,
|
|
in an ascending order. */
|
|
|
|
asc_or_desc = 1;
|
|
|
|
if (offset == low) {
|
|
asc_or_desc = -1;
|
|
}
|
|
|
|
/* How many out of order accessed pages can we ignore
|
|
when working out the access pattern for linear readahead */
|
|
threshold = ut_min((64 - srv_read_ahead_threshold),
|
|
BUF_READ_AHEAD_AREA(buf_pool));
|
|
|
|
fail_count = 0;
|
|
|
|
rw_lock_s_lock(&buf_pool->page_hash_latch);
|
|
for (i = low; i < high; i++) {
|
|
bpage = buf_page_hash_get(buf_pool, space, i);
|
|
|
|
if (bpage == NULL || !buf_page_is_accessed(bpage)) {
|
|
/* Not accessed */
|
|
fail_count++;
|
|
|
|
} else if (pred_bpage) {
|
|
/* Note that buf_page_is_accessed() returns
|
|
the time of the first access. If some blocks
|
|
of the extent existed in the buffer pool at
|
|
the time of a linear access pattern, the first
|
|
access times may be nonmonotonic, even though
|
|
the latest access times were linear. The
|
|
threshold (srv_read_ahead_factor) should help
|
|
a little against this. */
|
|
int res = ut_ulint_cmp(
|
|
buf_page_is_accessed(bpage),
|
|
buf_page_is_accessed(pred_bpage));
|
|
/* Accesses not in the right order */
|
|
if (res != 0 && res != asc_or_desc) {
|
|
fail_count++;
|
|
}
|
|
}
|
|
|
|
if (fail_count > threshold) {
|
|
/* Too many failures: return */
|
|
//buf_pool_mutex_exit(buf_pool);
|
|
rw_lock_s_unlock(&buf_pool->page_hash_latch);
|
|
return(0);
|
|
}
|
|
|
|
if (bpage && buf_page_is_accessed(bpage)) {
|
|
pred_bpage = bpage;
|
|
}
|
|
}
|
|
|
|
/* If we got this far, we know that enough pages in the area have
|
|
been accessed in the right order: linear read-ahead can be sensible */
|
|
|
|
bpage = buf_page_hash_get(buf_pool, space, offset);
|
|
|
|
if (bpage == NULL) {
|
|
//buf_pool_mutex_exit(buf_pool);
|
|
rw_lock_s_unlock(&buf_pool->page_hash_latch);
|
|
|
|
return(0);
|
|
}
|
|
|
|
switch (buf_page_get_state(bpage)) {
|
|
case BUF_BLOCK_ZIP_PAGE:
|
|
frame = bpage->zip.data;
|
|
break;
|
|
case BUF_BLOCK_FILE_PAGE:
|
|
frame = ((buf_block_t*) bpage)->frame;
|
|
break;
|
|
default:
|
|
ut_error;
|
|
break;
|
|
}
|
|
|
|
/* Read the natural predecessor and successor page addresses from
|
|
the page; NOTE that because the calling thread may have an x-latch
|
|
on the page, we do not acquire an s-latch on the page, this is to
|
|
prevent deadlocks. Even if we read values which are nonsense, the
|
|
algorithm will work. */
|
|
|
|
pred_offset = fil_page_get_prev(frame);
|
|
succ_offset = fil_page_get_next(frame);
|
|
|
|
//buf_pool_mutex_exit(buf_pool);
|
|
rw_lock_s_unlock(&buf_pool->page_hash_latch);
|
|
|
|
if ((offset == low) && (succ_offset == offset + 1)) {
|
|
|
|
/* This is ok, we can continue */
|
|
new_offset = pred_offset;
|
|
|
|
} else if ((offset == high - 1) && (pred_offset == offset - 1)) {
|
|
|
|
/* This is ok, we can continue */
|
|
new_offset = succ_offset;
|
|
} else {
|
|
/* Successor or predecessor not in the right order */
|
|
|
|
return(0);
|
|
}
|
|
|
|
low = (new_offset / buf_read_ahead_linear_area)
|
|
* buf_read_ahead_linear_area;
|
|
high = (new_offset / buf_read_ahead_linear_area + 1)
|
|
* buf_read_ahead_linear_area;
|
|
|
|
if ((new_offset != low) && (new_offset != high - 1)) {
|
|
/* This is not a border page of the area: return */
|
|
|
|
return(0);
|
|
}
|
|
|
|
if (high > fil_space_get_size(space)) {
|
|
/* The area is not whole, return */
|
|
|
|
return(0);
|
|
}
|
|
|
|
/* If we got this far, read-ahead can be sensible: do it */
|
|
|
|
ibuf_mode = inside_ibuf
|
|
? BUF_READ_IBUF_PAGES_ONLY | OS_AIO_SIMULATED_WAKE_LATER
|
|
: BUF_READ_ANY_PAGE | OS_AIO_SIMULATED_WAKE_LATER;
|
|
|
|
count = 0;
|
|
|
|
/* Since Windows XP seems to schedule the i/o handler thread
|
|
very eagerly, and consequently it does not wait for the
|
|
full read batch to be posted, we use special heuristics here */
|
|
|
|
os_aio_simulated_put_read_threads_to_sleep();
|
|
|
|
for (i = low; i < high; i++) {
|
|
/* It is only sensible to do read-ahead in the non-sync
|
|
aio mode: hence FALSE as the first parameter */
|
|
|
|
if (!ibuf_bitmap_page(zip_size, i)) {
|
|
count += buf_read_page_low(
|
|
&err, FALSE,
|
|
ibuf_mode,
|
|
space, zip_size, FALSE, tablespace_version, i, trx);
|
|
if (err == DB_TABLESPACE_DELETED) {
|
|
ut_print_timestamp(stderr);
|
|
fprintf(stderr,
|
|
" InnoDB: Warning: in"
|
|
" linear readahead trying to access\n"
|
|
"InnoDB: tablespace %lu page %lu,\n"
|
|
"InnoDB: but the tablespace does not"
|
|
" exist or is just being dropped.\n",
|
|
(ulong) space, (ulong) i);
|
|
}
|
|
}
|
|
}
|
|
|
|
/* In simulated aio we wake the aio handler threads only after
|
|
queuing all aio requests, in native aio the following call does
|
|
nothing: */
|
|
|
|
os_aio_simulated_wake_handler_threads();
|
|
|
|
/* Flush pages from the end of the LRU list if necessary */
|
|
buf_flush_free_margin(buf_pool, TRUE);
|
|
|
|
#ifdef UNIV_DEBUG
|
|
if (buf_debug_prints && (count > 0)) {
|
|
fprintf(stderr,
|
|
"LINEAR read-ahead space %lu offset %lu pages %lu\n",
|
|
(ulong) space, (ulong) offset, (ulong) count);
|
|
}
|
|
#endif /* UNIV_DEBUG */
|
|
|
|
/* Read ahead is considered one I/O operation for the purpose of
|
|
LRU policy decision. */
|
|
buf_LRU_stat_inc_io();
|
|
|
|
buf_pool->stat.n_ra_pages_read += count;
|
|
return(count);
|
|
}
|
|
|
|
/********************************************************************//**
|
|
Issues read requests for pages which the ibuf module wants to read in, in
|
|
order to contract the insert buffer tree. Technically, this function is like
|
|
a read-ahead function. */
|
|
UNIV_INTERN
|
|
void
|
|
buf_read_ibuf_merge_pages(
|
|
/*======================*/
|
|
ibool sync, /*!< in: TRUE if the caller
|
|
wants this function to wait
|
|
for the highest address page
|
|
to get read in, before this
|
|
function returns */
|
|
const ulint* space_ids, /*!< in: array of space ids */
|
|
const ib_int64_t* space_versions,/*!< in: the spaces must have
|
|
this version number
|
|
(timestamp), otherwise we
|
|
discard the read; we use this
|
|
to cancel reads if DISCARD +
|
|
IMPORT may have changed the
|
|
tablespace size */
|
|
const ulint* page_nos, /*!< in: array of page numbers
|
|
to read, with the highest page
|
|
number the last in the
|
|
array */
|
|
ulint n_stored) /*!< in: number of elements
|
|
in the arrays */
|
|
{
|
|
ulint i;
|
|
|
|
#ifdef UNIV_IBUF_DEBUG
|
|
ut_a(n_stored < UNIV_PAGE_SIZE);
|
|
#endif
|
|
|
|
for (i = 0; i < n_stored; i++) {
|
|
ulint err;
|
|
buf_pool_t* buf_pool;
|
|
ulint zip_size = fil_space_get_zip_size(space_ids[i]);
|
|
|
|
buf_pool = buf_pool_get(space_ids[i], page_nos[i]);
|
|
|
|
while (buf_pool->n_pend_reads
|
|
> buf_pool->curr_size / BUF_READ_AHEAD_PEND_LIMIT) {
|
|
os_thread_sleep(500000);
|
|
}
|
|
|
|
if (UNIV_UNLIKELY(zip_size == ULINT_UNDEFINED)) {
|
|
|
|
goto tablespace_deleted;
|
|
}
|
|
|
|
buf_read_page_low(&err, sync && (i + 1 == n_stored),
|
|
BUF_READ_ANY_PAGE, space_ids[i],
|
|
zip_size, TRUE, space_versions[i],
|
|
page_nos[i], NULL);
|
|
|
|
if (UNIV_UNLIKELY(err == DB_TABLESPACE_DELETED)) {
|
|
tablespace_deleted:
|
|
/* We have deleted or are deleting the single-table
|
|
tablespace: remove the entries for that page */
|
|
|
|
ibuf_merge_or_delete_for_page(NULL, space_ids[i],
|
|
page_nos[i],
|
|
zip_size, FALSE);
|
|
}
|
|
}
|
|
|
|
os_aio_simulated_wake_handler_threads();
|
|
|
|
/* Flush pages from the end of all the LRU lists if necessary */
|
|
buf_flush_free_margins(FALSE);
|
|
|
|
#ifdef UNIV_DEBUG
|
|
if (buf_debug_prints) {
|
|
fprintf(stderr,
|
|
"Ibuf merge read-ahead space %lu pages %lu\n",
|
|
(ulong) space_ids[0], (ulong) n_stored);
|
|
}
|
|
#endif /* UNIV_DEBUG */
|
|
}
|
|
|
|
/********************************************************************//**
|
|
Issues read requests for pages which recovery wants to read in. */
|
|
UNIV_INTERN
|
|
void
|
|
buf_read_recv_pages(
|
|
/*================*/
|
|
ibool sync, /*!< in: TRUE if the caller
|
|
wants this function to wait
|
|
for the highest address page
|
|
to get read in, before this
|
|
function returns */
|
|
ulint space, /*!< in: space id */
|
|
ulint zip_size, /*!< in: compressed page size in
|
|
bytes, or 0 */
|
|
const ulint* page_nos, /*!< in: array of page numbers
|
|
to read, with the highest page
|
|
number the last in the
|
|
array */
|
|
ulint n_stored) /*!< in: number of page numbers
|
|
in the array */
|
|
{
|
|
ib_int64_t tablespace_version;
|
|
ulint count;
|
|
ulint err;
|
|
ulint i;
|
|
|
|
zip_size = fil_space_get_zip_size(space);
|
|
|
|
if (UNIV_UNLIKELY(zip_size == ULINT_UNDEFINED)) {
|
|
/* It is a single table tablespace and the .ibd file is
|
|
missing: do nothing */
|
|
|
|
/* the log records should be treated here same reason
|
|
for http://bugs.mysql.com/bug.php?id=43948 */
|
|
|
|
if (recv_recovery_is_on()) {
|
|
recv_addr_t* recv_addr;
|
|
|
|
mutex_enter(&(recv_sys->mutex));
|
|
|
|
if (recv_sys->apply_log_recs == FALSE) {
|
|
mutex_exit(&(recv_sys->mutex));
|
|
goto not_to_recover;
|
|
}
|
|
|
|
for (i = 0; i < n_stored; i++) {
|
|
/* recv_get_fil_addr_struct() */
|
|
recv_addr = HASH_GET_FIRST(recv_sys->addr_hash,
|
|
hash_calc_hash(ut_fold_ulint_pair(space, page_nos[i]),
|
|
recv_sys->addr_hash));
|
|
while (recv_addr) {
|
|
if ((recv_addr->space == space)
|
|
&& (recv_addr->page_no == page_nos[i])) {
|
|
break;
|
|
}
|
|
recv_addr = HASH_GET_NEXT(addr_hash, recv_addr);
|
|
}
|
|
|
|
if ((recv_addr == NULL)
|
|
|| (recv_addr->state == RECV_BEING_PROCESSED)
|
|
|| (recv_addr->state == RECV_PROCESSED)) {
|
|
continue;
|
|
}
|
|
|
|
recv_addr->state = RECV_PROCESSED;
|
|
|
|
ut_a(recv_sys->n_addrs);
|
|
recv_sys->n_addrs--;
|
|
}
|
|
|
|
mutex_exit(&(recv_sys->mutex));
|
|
|
|
fprintf(stderr, " (cannot find space: %lu)", space);
|
|
}
|
|
not_to_recover:
|
|
|
|
return;
|
|
}
|
|
|
|
tablespace_version = fil_space_get_version(space);
|
|
|
|
for (i = 0; i < n_stored; i++) {
|
|
buf_pool_t* buf_pool;
|
|
|
|
count = 0;
|
|
|
|
os_aio_print_debug = FALSE;
|
|
buf_pool = buf_pool_get(space, page_nos[i]);
|
|
while (buf_pool->n_pend_reads >= recv_n_pool_free_frames / 2) {
|
|
|
|
os_aio_simulated_wake_handler_threads();
|
|
os_thread_sleep(10000);
|
|
|
|
count++;
|
|
|
|
if (count > 1000) {
|
|
fprintf(stderr,
|
|
"InnoDB: Error: InnoDB has waited for"
|
|
" 10 seconds for pending\n"
|
|
"InnoDB: reads to the buffer pool to"
|
|
" be finished.\n"
|
|
"InnoDB: Number of pending reads %lu,"
|
|
" pending pread calls %lu\n",
|
|
(ulong) buf_pool->n_pend_reads,
|
|
(ulong)os_file_n_pending_preads);
|
|
|
|
os_aio_print_debug = TRUE;
|
|
}
|
|
}
|
|
|
|
os_aio_print_debug = FALSE;
|
|
|
|
if ((i + 1 == n_stored) && sync) {
|
|
buf_read_page_low(&err, TRUE, BUF_READ_ANY_PAGE, space,
|
|
zip_size, TRUE, tablespace_version,
|
|
page_nos[i], NULL);
|
|
} else {
|
|
buf_read_page_low(&err, FALSE, BUF_READ_ANY_PAGE
|
|
| OS_AIO_SIMULATED_WAKE_LATER,
|
|
space, zip_size, TRUE,
|
|
tablespace_version, page_nos[i], NULL);
|
|
}
|
|
}
|
|
|
|
os_aio_simulated_wake_handler_threads();
|
|
|
|
/* Flush pages from the end of all the LRU lists if necessary */
|
|
buf_flush_free_margins(FALSE);
|
|
|
|
#ifdef UNIV_DEBUG
|
|
if (buf_debug_prints) {
|
|
fprintf(stderr,
|
|
"Recovery applies read-ahead pages %lu\n",
|
|
(ulong) n_stored);
|
|
}
|
|
#endif /* UNIV_DEBUG */
|
|
}
|