mirror of
https://github.com/MariaDB/server.git
synced 2025-01-27 01:04:19 +01:00
Reduce buffer pool mutex contention under >= 4 big concurrent
CPU-bound SELECT queries. (Bug #15815) Fix: replace the mutex by one mutex protecting the 'flush list' (and the free list) and several mutexes protecting portions of the buffer pool, where we keep several indivudual LRU lists of pages. This patch is from Sunny Bains and Heikki Tuuri.
This commit is contained in:
marko
parent
c08c1e65c9
commit
0dda8605fa
5 changed files with 244 additions and 96 deletions
168
buf/buf0buf.c
168
buf/buf0buf.c
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@ -221,6 +221,9 @@ in the free list to the frames.
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5) When we have AWE enabled, we disable adaptive hash indexes.
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*/
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/* Value in microseconds */
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static const int WAIT_FOR_READ = 20000;
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buf_pool_t* buf_pool = NULL; /* The buffer buf_pool of the database */
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#ifdef UNIV_DEBUG
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@ -539,6 +542,8 @@ buf_block_init(
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block->n_pointers = 0;
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mutex_create(&block->mutex, SYNC_BUF_BLOCK);
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rw_lock_create(&block->lock, SYNC_LEVEL_VARYING);
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ut_ad(rw_lock_validate(&(block->lock)));
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@ -813,8 +818,15 @@ buf_awe_map_page_to_frame(
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bck = UT_LIST_GET_LAST(buf_pool->awe_LRU_free_mapped);
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while (bck) {
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if (bck->state == BUF_BLOCK_FILE_PAGE
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&& (bck->buf_fix_count != 0 || bck->io_fix != 0)) {
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ibool skip;
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mutex_enter(&bck->mutex);
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skip = (bck->state == BUF_BLOCK_FILE_PAGE
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&& (bck->buf_fix_count != 0 || bck->io_fix != 0));
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if (skip) {
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mutex_exit(&bck->mutex);
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/* We have to skip this */
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bck = UT_LIST_GET_PREV(awe_LRU_free_mapped, bck);
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@ -848,6 +860,8 @@ buf_awe_map_page_to_frame(
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buf_pool->n_pages_awe_remapped++;
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mutex_exit(&bck->mutex);
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return;
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}
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}
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@ -886,13 +900,22 @@ buf_block_make_young(
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/*=================*/
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buf_block_t* block) /* in: block to make younger */
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{
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if (buf_pool->freed_page_clock >= block->freed_page_clock
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+ 1 + (buf_pool->curr_size / 1024)) {
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#ifdef UNIV_SYNC_DEBUG
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ut_ad(!mutex_own(&(buf_pool->mutex)));
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#endif /* UNIV_SYNC_DEBUG */
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/* Note that we read freed_page_clock's without holding any mutex:
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this is allowed since the result is used only in heuristics */
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if (buf_pool->freed_page_clock >= block->freed_page_clock
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+ 1 + (buf_pool->curr_size / 4)) {
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mutex_enter(&buf_pool->mutex);
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/* There has been freeing activity in the LRU list:
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best to move to the head of the LRU list */
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buf_LRU_make_block_young(block);
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mutex_exit(&buf_pool->mutex);
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}
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}
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@ -927,12 +950,16 @@ buf_block_free(
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/*===========*/
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buf_block_t* block) /* in, own: block to be freed */
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{
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ut_a(block->state != BUF_BLOCK_FILE_PAGE);
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mutex_enter(&(buf_pool->mutex));
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mutex_enter(&block->mutex);
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ut_a(block->state != BUF_BLOCK_FILE_PAGE);
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buf_LRU_block_free_non_file_page(block);
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mutex_exit(&block->mutex);
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mutex_exit(&(buf_pool->mutex));
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}
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@ -1151,9 +1178,8 @@ buf_page_get_gen(
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#endif
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buf_pool->n_page_gets++;
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loop:
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mutex_enter_fast(&(buf_pool->mutex));
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block = NULL;
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mutex_enter_fast(&(buf_pool->mutex));
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if (guess) {
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block = buf_block_align(guess);
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@ -1191,6 +1217,8 @@ loop:
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goto loop;
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}
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mutex_enter(&block->mutex);
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ut_a(block->state == BUF_BLOCK_FILE_PAGE);
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must_read = FALSE;
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@ -1200,9 +1228,9 @@ loop:
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must_read = TRUE;
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if (mode == BUF_GET_IF_IN_POOL) {
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/* The page is only being read to buffer */
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mutex_exit(&(buf_pool->mutex));
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mutex_exit(&buf_pool->mutex);
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mutex_exit(&block->mutex);
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return(NULL);
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}
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@ -1226,7 +1254,7 @@ loop:
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#else
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buf_block_buf_fix_inc(block);
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#endif
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buf_block_make_young(block);
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mutex_exit(&buf_pool->mutex);
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/* Check if this is the first access to the page */
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@ -1234,10 +1262,13 @@ loop:
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block->accessed = TRUE;
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mutex_exit(&block->mutex);
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buf_block_make_young(block);
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#ifdef UNIV_DEBUG_FILE_ACCESSES
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ut_a(block->file_page_was_freed == FALSE);
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#endif
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mutex_exit(&(buf_pool->mutex));
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#ifdef UNIV_DEBUG
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buf_dbg_counter++;
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@ -1262,13 +1293,14 @@ loop:
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}
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if (!success) {
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mutex_enter(&(buf_pool->mutex));
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mutex_enter(&block->mutex);
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block->buf_fix_count--;
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mutex_exit(&block->mutex);
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#ifdef UNIV_SYNC_DEBUG
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rw_lock_s_unlock(&(block->debug_latch));
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#endif
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mutex_exit(&(buf_pool->mutex));
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return(NULL);
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}
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@ -1279,18 +1311,16 @@ loop:
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completes */
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for (;;) {
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mutex_enter(&(buf_pool->mutex));
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mutex_enter(&block->mutex);
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if (block->io_fix == BUF_IO_READ) {
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mutex_exit(&(buf_pool->mutex));
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mutex_exit(&block->mutex);
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/* Sleep 20 milliseconds */
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os_thread_sleep(20000);
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os_thread_sleep(WAIT_FOR_READ);
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} else {
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mutex_exit(&(buf_pool->mutex));
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mutex_exit(&block->mutex);
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break;
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}
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@ -1349,14 +1379,14 @@ buf_page_optimistic_get_func(
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ut_ad(mtr && block);
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ut_ad((rw_latch == RW_S_LATCH) || (rw_latch == RW_X_LATCH));
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mutex_enter(&(buf_pool->mutex));
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/* If AWE is used, block may have a different frame now, e.g., NULL */
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mutex_enter(&block->mutex);
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if (UNIV_UNLIKELY(block->state != BUF_BLOCK_FILE_PAGE)
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|| UNIV_UNLIKELY(block->frame != guess)) {
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exit_func:
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mutex_exit(&(buf_pool->mutex));
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mutex_exit(&block->mutex);
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return(FALSE);
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}
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@ -1366,16 +1396,15 @@ exit_func:
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#else
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buf_block_buf_fix_inc(block);
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#endif
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accessed = block->accessed;
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block->accessed = TRUE;
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mutex_exit(&block->mutex);
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buf_block_make_young(block);
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/* Check if this is the first access to the page */
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accessed = block->accessed;
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block->accessed = TRUE;
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mutex_exit(&(buf_pool->mutex));
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ut_ad(!ibuf_inside() || ibuf_page(block->space, block->offset));
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if (rw_latch == RW_S_LATCH) {
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@ -1389,13 +1418,16 @@ exit_func:
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}
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if (UNIV_UNLIKELY(!success)) {
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mutex_enter(&(buf_pool->mutex));
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mutex_enter(&block->mutex);
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block->buf_fix_count--;
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mutex_exit(&block->mutex);
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#ifdef UNIV_SYNC_DEBUG
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rw_lock_s_unlock(&(block->debug_latch));
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#endif
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goto exit_func;
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return(FALSE);
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}
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if (UNIV_UNLIKELY(!UT_DULINT_EQ(modify_clock, block->modify_clock))) {
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@ -1408,13 +1440,16 @@ exit_func:
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rw_lock_x_unlock(&(block->lock));
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}
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mutex_enter(&(buf_pool->mutex));
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mutex_enter(&block->mutex);
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block->buf_fix_count--;
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mutex_exit(&block->mutex);
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#ifdef UNIV_SYNC_DEBUG
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rw_lock_s_unlock(&(block->debug_latch));
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#endif
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goto exit_func;
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return(FALSE);
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}
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mtr_memo_push(mtr, block, fix_type);
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@ -1471,10 +1506,10 @@ buf_page_get_known_nowait(
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ut_ad(mtr);
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ut_ad((rw_latch == RW_S_LATCH) || (rw_latch == RW_X_LATCH));
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mutex_enter(&(buf_pool->mutex));
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block = buf_block_align(guess);
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mutex_enter(&block->mutex);
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if (block->state == BUF_BLOCK_REMOVE_HASH) {
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/* Another thread is just freeing the block from the LRU list
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of the buffer pool: do not try to access this page; this
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@ -1483,7 +1518,7 @@ buf_page_get_known_nowait(
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we have already removed it from the page address hash table
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of the buffer pool. */
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mutex_exit(&(buf_pool->mutex));
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mutex_exit(&block->mutex);
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return(FALSE);
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}
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@ -1495,12 +1530,12 @@ buf_page_get_known_nowait(
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#else
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buf_block_buf_fix_inc(block);
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#endif
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mutex_exit(&block->mutex);
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if (mode == BUF_MAKE_YOUNG) {
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buf_block_make_young(block);
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}
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mutex_exit(&(buf_pool->mutex));
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ut_ad(!ibuf_inside() || (mode == BUF_KEEP_OLD));
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if (rw_latch == RW_S_LATCH) {
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@ -1514,13 +1549,15 @@ buf_page_get_known_nowait(
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}
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if (!success) {
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mutex_enter(&(buf_pool->mutex));
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mutex_enter(&block->mutex);
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block->buf_fix_count--;
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mutex_exit(&block->mutex);
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#ifdef UNIV_SYNC_DEBUG
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rw_lock_s_unlock(&(block->debug_latch));
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#endif
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mutex_exit(&(buf_pool->mutex));
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return(FALSE);
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}
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@ -1568,7 +1605,6 @@ buf_page_init_for_backup_restore(
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block->offset = offset;
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block->lock_hash_val = 0;
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block->lock_mutex = NULL;
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block->freed_page_clock = 0;
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@ -1601,6 +1637,7 @@ buf_page_init(
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{
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#ifdef UNIV_SYNC_DEBUG
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ut_ad(mutex_own(&(buf_pool->mutex)));
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ut_ad(mutex_own(&(block->mutex)));
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#endif /* UNIV_SYNC_DEBUG */
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ut_a(block->state != BUF_BLOCK_FILE_PAGE);
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@ -1615,7 +1652,6 @@ buf_page_init(
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block->index = NULL;
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block->lock_hash_val = lock_rec_hash(space, offset);
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block->lock_mutex = NULL;
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/* Insert into the hash table of file pages */
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@ -1709,6 +1745,7 @@ buf_page_init_for_read(
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ut_a(block);
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mutex_enter(&(buf_pool->mutex));
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mutex_enter(&block->mutex);
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if (fil_tablespace_deleted_or_being_deleted_in_mem(
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space, tablespace_version)) {
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@ -1722,7 +1759,9 @@ buf_page_init_for_read(
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deleted or is being deleted, or the page is
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already in buf_pool, return */
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mutex_exit(&block->mutex);
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mutex_exit(&(buf_pool->mutex));
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buf_block_free(block);
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if (mode == BUF_READ_IBUF_PAGES_ONLY) {
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@ -1742,6 +1781,7 @@ buf_page_init_for_read(
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buf_LRU_add_block(block, TRUE); /* TRUE == to old blocks */
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block->io_fix = BUF_IO_READ;
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buf_pool->n_pend_reads++;
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/* We set a pass-type x-lock on the frame because then the same
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@ -1753,6 +1793,7 @@ buf_page_init_for_read(
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rw_lock_x_lock_gen(&(block->lock), BUF_IO_READ);
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mutex_exit(&block->mutex);
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mutex_exit(&(buf_pool->mutex));
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if (mode == BUF_READ_IBUF_PAGES_ONLY) {
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@ -1817,6 +1858,8 @@ buf_page_create(
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block = free_block;
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mutex_enter(&block->mutex);
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buf_page_init(space, offset, block);
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/* The block must be put to the LRU list */
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@ -1827,13 +1870,15 @@ buf_page_create(
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#else
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buf_block_buf_fix_inc(block);
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#endif
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buf_pool->n_pages_created++;
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mutex_exit(&(buf_pool->mutex));
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mtr_memo_push(mtr, block, MTR_MEMO_BUF_FIX);
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block->accessed = TRUE;
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buf_pool->n_pages_created++;
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mutex_exit(&(buf_pool->mutex));
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mutex_exit(&block->mutex);
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/* Delete possible entries for the page from the insert buffer:
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such can exist if the page belonged to an index which was dropped */
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@ -1885,6 +1930,12 @@ buf_page_io_complete(
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ut_a(block->state == BUF_BLOCK_FILE_PAGE);
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/* We do not need protect block->io_fix here by block->mutex to read
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it because this is the only function where we can change the value
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from BUF_IO_READ or BUF_IO_WRITE to some other value, and our code
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ensures that this is the only thread that handles the i/o for this
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block. */
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io_type = block->io_fix;
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if (io_type == BUF_IO_READ) {
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@ -1986,11 +2037,12 @@ buf_page_io_complete(
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}
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}
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mutex_enter(&(buf_pool->mutex));
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mutex_enter(&block->mutex);
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#ifdef UNIV_IBUF_DEBUG
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ut_a(ibuf_count_get(block->space, block->offset) == 0);
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#endif
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mutex_enter(&(buf_pool->mutex));
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/* Because this thread which does the unlocking is not the same that
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did the locking, we use a pass value != 0 in unlock, which simply
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removes the newest lock debug record, without checking the thread
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@ -2033,6 +2085,7 @@ buf_page_io_complete(
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#endif /* UNIV_DEBUG */
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}
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mutex_exit(&block->mutex);
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mutex_exit(&(buf_pool->mutex));
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#ifdef UNIV_DEBUG
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@ -2095,6 +2148,8 @@ buf_validate(void)
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block = buf_pool_get_nth_block(buf_pool, i);
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mutex_enter(&block->mutex);
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if (block->state == BUF_BLOCK_FILE_PAGE) {
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ut_a(buf_page_hash_get(block->space,
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@ -2139,6 +2194,8 @@ buf_validate(void)
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} else if (block->state == BUF_BLOCK_NOT_USED) {
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n_free++;
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}
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mutex_exit(&block->mutex);
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}
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if (n_lru + n_free > buf_pool->curr_size) {
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@ -2286,9 +2343,14 @@ buf_get_latched_pages_number(void)
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block = buf_pool_get_nth_block(buf_pool, i);
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if (((block->buf_fix_count != 0) || (block->io_fix != 0))
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&& block->magic_n == BUF_BLOCK_MAGIC_N) {
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fixed_pages_number++;
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if (block->magic_n == BUF_BLOCK_MAGIC_N) {
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mutex_enter(&block->mutex);
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if (block->buf_fix_count != 0 || block->io_fix != 0) {
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fixed_pages_number++;
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}
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mutex_exit(&block->mutex);
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}
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}
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@ -2458,6 +2520,8 @@ buf_all_freed(void)
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block = buf_pool_get_nth_block(buf_pool, i);
|
||||
|
||||
mutex_enter(&block->mutex);
|
||||
|
||||
if (block->state == BUF_BLOCK_FILE_PAGE) {
|
||||
|
||||
if (!buf_flush_ready_for_replace(block)) {
|
||||
|
|
@ -2469,6 +2533,8 @@ buf_all_freed(void)
|
|||
ut_error;
|
||||
}
|
||||
}
|
||||
|
||||
mutex_exit(&block->mutex);
|
||||
}
|
||||
|
||||
mutex_exit(&(buf_pool->mutex));
|
||||
|
|
|
|||
|
|
@ -113,6 +113,7 @@ buf_flush_ready_for_replace(
|
|||
{
|
||||
#ifdef UNIV_SYNC_DEBUG
|
||||
ut_ad(mutex_own(&(buf_pool->mutex)));
|
||||
ut_ad(mutex_own(&block->mutex));
|
||||
#endif /* UNIV_SYNC_DEBUG */
|
||||
if (block->state != BUF_BLOCK_FILE_PAGE) {
|
||||
ut_print_timestamp(stderr);
|
||||
|
|
@ -148,6 +149,7 @@ buf_flush_ready_for_flush(
|
|||
{
|
||||
#ifdef UNIV_SYNC_DEBUG
|
||||
ut_ad(mutex_own(&(buf_pool->mutex)));
|
||||
ut_ad(mutex_own(&(block->mutex)));
|
||||
#endif /* UNIV_SYNC_DEBUG */
|
||||
ut_a(block->state == BUF_BLOCK_FILE_PAGE);
|
||||
|
||||
|
|
@ -559,8 +561,15 @@ buf_flush_try_page(
|
|||
|
||||
ut_a(!block || block->state == BUF_BLOCK_FILE_PAGE);
|
||||
|
||||
if (!block) {
|
||||
mutex_exit(&(buf_pool->mutex));
|
||||
return(0);
|
||||
}
|
||||
|
||||
mutex_enter(&block->mutex);
|
||||
|
||||
if (flush_type == BUF_FLUSH_LIST
|
||||
&& block && buf_flush_ready_for_flush(block, flush_type)) {
|
||||
&& buf_flush_ready_for_flush(block, flush_type)) {
|
||||
|
||||
block->io_fix = BUF_IO_WRITE;
|
||||
|
||||
|
|
@ -598,6 +607,7 @@ buf_flush_try_page(
|
|||
locked = TRUE;
|
||||
}
|
||||
|
||||
mutex_exit(&block->mutex);
|
||||
mutex_exit(&(buf_pool->mutex));
|
||||
|
||||
if (!locked) {
|
||||
|
|
@ -618,7 +628,7 @@ buf_flush_try_page(
|
|||
|
||||
return(1);
|
||||
|
||||
} else if (flush_type == BUF_FLUSH_LRU && block
|
||||
} else if (flush_type == BUF_FLUSH_LRU
|
||||
&& buf_flush_ready_for_flush(block, flush_type)) {
|
||||
|
||||
/* VERY IMPORTANT:
|
||||
|
|
@ -659,13 +669,14 @@ buf_flush_try_page(
|
|||
buf_pool mutex: this ensures that the latch is acquired
|
||||
immediately. */
|
||||
|
||||
mutex_exit(&block->mutex);
|
||||
mutex_exit(&(buf_pool->mutex));
|
||||
|
||||
buf_flush_write_block_low(block);
|
||||
|
||||
return(1);
|
||||
|
||||
} else if (flush_type == BUF_FLUSH_SINGLE_PAGE && block
|
||||
} else if (flush_type == BUF_FLUSH_SINGLE_PAGE
|
||||
&& buf_flush_ready_for_flush(block, flush_type)) {
|
||||
|
||||
block->io_fix = BUF_IO_WRITE;
|
||||
|
|
@ -692,6 +703,7 @@ buf_flush_try_page(
|
|||
|
||||
(buf_pool->n_flush[flush_type])++;
|
||||
|
||||
mutex_exit(&block->mutex);
|
||||
mutex_exit(&(buf_pool->mutex));
|
||||
|
||||
rw_lock_s_lock_gen(&(block->lock), BUF_IO_WRITE);
|
||||
|
|
@ -709,11 +721,12 @@ buf_flush_try_page(
|
|||
buf_flush_write_block_low(block);
|
||||
|
||||
return(1);
|
||||
} else {
|
||||
mutex_exit(&(buf_pool->mutex));
|
||||
|
||||
return(0);
|
||||
}
|
||||
|
||||
mutex_exit(&block->mutex);
|
||||
mutex_exit(&(buf_pool->mutex));
|
||||
|
||||
return(0);
|
||||
}
|
||||
|
||||
/***************************************************************
|
||||
|
|
@ -758,34 +771,48 @@ buf_flush_try_neighbors(
|
|||
block = buf_page_hash_get(space, i);
|
||||
ut_a(!block || block->state == BUF_BLOCK_FILE_PAGE);
|
||||
|
||||
if (block && flush_type == BUF_FLUSH_LRU && i != offset
|
||||
&& !block->old) {
|
||||
if (!block) {
|
||||
|
||||
continue;
|
||||
|
||||
} else if (flush_type == BUF_FLUSH_LRU && i != offset
|
||||
&& !block->old) {
|
||||
|
||||
/* We avoid flushing 'non-old' blocks in an LRU flush,
|
||||
because the flushed blocks are soon freed */
|
||||
|
||||
continue;
|
||||
}
|
||||
} else {
|
||||
|
||||
if (block && buf_flush_ready_for_flush(block, flush_type)
|
||||
&& (i == offset || block->buf_fix_count == 0)) {
|
||||
/* We only try to flush those neighbors != offset
|
||||
where the buf fix count is zero, as we then know that
|
||||
we probably can latch the page without a semaphore
|
||||
wait. Semaphore waits are expensive because we must
|
||||
flush the doublewrite buffer before we start
|
||||
waiting. */
|
||||
mutex_enter(&block->mutex);
|
||||
|
||||
mutex_exit(&(buf_pool->mutex));
|
||||
if (buf_flush_ready_for_flush(block, flush_type)
|
||||
&& (i == offset || block->buf_fix_count == 0)) {
|
||||
/* We only try to flush those
|
||||
neighbors != offset where the buf fix count is
|
||||
zero, as we then know that we probably can
|
||||
latch the page without a semaphore wait.
|
||||
Semaphore waits are expensive because we must
|
||||
flush the doublewrite buffer before we start
|
||||
waiting. */
|
||||
|
||||
/* Note: as we release the buf_pool mutex above, in
|
||||
buf_flush_try_page we cannot be sure the page is still
|
||||
in a flushable state: therefore we check it again
|
||||
inside that function. */
|
||||
mutex_exit(&block->mutex);
|
||||
|
||||
count += buf_flush_try_page(space, i, flush_type);
|
||||
mutex_exit(&(buf_pool->mutex));
|
||||
|
||||
mutex_enter(&(buf_pool->mutex));
|
||||
/* Note: as we release the buf_pool mutex
|
||||
above, in buf_flush_try_page we cannot be sure
|
||||
the page is still in a flushable state:
|
||||
therefore we check it again inside that
|
||||
function. */
|
||||
|
||||
count += buf_flush_try_page(space, i,
|
||||
flush_type);
|
||||
|
||||
mutex_enter(&(buf_pool->mutex));
|
||||
} else {
|
||||
mutex_exit(&block->mutex);
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
|
|
@ -879,12 +906,15 @@ buf_flush_batch(
|
|||
while ((block != NULL) && !found) {
|
||||
ut_a(block->state == BUF_BLOCK_FILE_PAGE);
|
||||
|
||||
mutex_enter(&block->mutex);
|
||||
|
||||
if (buf_flush_ready_for_flush(block, flush_type)) {
|
||||
|
||||
found = TRUE;
|
||||
space = block->space;
|
||||
offset = block->offset;
|
||||
|
||||
mutex_exit(&block->mutex);
|
||||
mutex_exit(&(buf_pool->mutex));
|
||||
|
||||
old_page_count = page_count;
|
||||
|
|
@ -901,10 +931,14 @@ buf_flush_batch(
|
|||
|
||||
} else if (flush_type == BUF_FLUSH_LRU) {
|
||||
|
||||
mutex_exit(&block->mutex);
|
||||
|
||||
block = UT_LIST_GET_PREV(LRU, block);
|
||||
} else {
|
||||
ut_ad(flush_type == BUF_FLUSH_LIST);
|
||||
|
||||
mutex_exit(&block->mutex);
|
||||
|
||||
block = UT_LIST_GET_PREV(flush_list, block);
|
||||
}
|
||||
}
|
||||
|
|
@ -986,10 +1020,14 @@ buf_flush_LRU_recommendation(void)
|
|||
+ BUF_FLUSH_EXTRA_MARGIN)
|
||||
&& (distance < BUF_LRU_FREE_SEARCH_LEN)) {
|
||||
|
||||
mutex_enter(&block->mutex);
|
||||
|
||||
if (buf_flush_ready_for_replace(block)) {
|
||||
n_replaceable++;
|
||||
}
|
||||
|
||||
mutex_exit(&block->mutex);
|
||||
|
||||
distance++;
|
||||
|
||||
block = UT_LIST_GET_PREV(LRU, block);
|
||||
|
|
|
|||
|
|
@ -86,6 +86,9 @@ scan_again:
|
|||
block = UT_LIST_GET_LAST(buf_pool->LRU);
|
||||
|
||||
while (block != NULL) {
|
||||
|
||||
mutex_enter(&block->mutex);
|
||||
|
||||
ut_a(block->state == BUF_BLOCK_FILE_PAGE);
|
||||
|
||||
if (block->space == id
|
||||
|
|
@ -112,6 +115,8 @@ scan_again:
|
|||
if (block->is_hashed) {
|
||||
page_no = block->offset;
|
||||
|
||||
mutex_exit(&block->mutex);
|
||||
|
||||
mutex_exit(&(buf_pool->mutex));
|
||||
|
||||
/* Note that the following call will acquire
|
||||
|
|
@ -138,6 +143,7 @@ scan_again:
|
|||
buf_LRU_block_free_hashed_page(block);
|
||||
}
|
||||
next_page:
|
||||
mutex_exit(&block->mutex);
|
||||
block = UT_LIST_GET_PREV(LRU, block);
|
||||
}
|
||||
|
||||
|
|
@ -211,6 +217,9 @@ buf_LRU_search_and_free_block(
|
|||
|
||||
while (block != NULL) {
|
||||
ut_a(block->in_LRU_list);
|
||||
|
||||
mutex_enter(&block->mutex);
|
||||
|
||||
if (buf_flush_ready_for_replace(block)) {
|
||||
|
||||
#ifdef UNIV_DEBUG
|
||||
|
|
@ -226,6 +235,7 @@ buf_LRU_search_and_free_block(
|
|||
buf_LRU_block_remove_hashed_page(block);
|
||||
|
||||
mutex_exit(&(buf_pool->mutex));
|
||||
mutex_exit(&block->mutex);
|
||||
|
||||
/* Remove possible adaptive hash index built on the
|
||||
page; in the case of AWE the block may not have a
|
||||
|
|
@ -234,15 +244,21 @@ buf_LRU_search_and_free_block(
|
|||
if (block->frame) {
|
||||
btr_search_drop_page_hash_index(block->frame);
|
||||
}
|
||||
mutex_enter(&(buf_pool->mutex));
|
||||
|
||||
ut_a(block->buf_fix_count == 0);
|
||||
|
||||
mutex_enter(&(buf_pool->mutex));
|
||||
mutex_enter(&block->mutex);
|
||||
|
||||
buf_LRU_block_free_hashed_page(block);
|
||||
freed = TRUE;
|
||||
mutex_exit(&block->mutex);
|
||||
|
||||
break;
|
||||
}
|
||||
|
||||
mutex_exit(&block->mutex);
|
||||
|
||||
block = UT_LIST_GET_PREV(LRU, block);
|
||||
distance++;
|
||||
|
||||
|
|
@ -428,8 +444,12 @@ loop:
|
|||
}
|
||||
}
|
||||
|
||||
mutex_enter(&block->mutex);
|
||||
|
||||
block->state = BUF_BLOCK_READY_FOR_USE;
|
||||
|
||||
mutex_exit(&block->mutex);
|
||||
|
||||
mutex_exit(&(buf_pool->mutex));
|
||||
|
||||
if (started_monitor) {
|
||||
|
|
@ -838,6 +858,7 @@ buf_LRU_block_free_non_file_page(
|
|||
{
|
||||
#ifdef UNIV_SYNC_DEBUG
|
||||
ut_ad(mutex_own(&(buf_pool->mutex)));
|
||||
ut_ad(mutex_own(&block->mutex));
|
||||
#endif /* UNIV_SYNC_DEBUG */
|
||||
ut_ad(block);
|
||||
|
||||
|
|
@ -877,6 +898,7 @@ buf_LRU_block_remove_hashed_page(
|
|||
{
|
||||
#ifdef UNIV_SYNC_DEBUG
|
||||
ut_ad(mutex_own(&(buf_pool->mutex)));
|
||||
ut_ad(mutex_own(&block->mutex));
|
||||
#endif /* UNIV_SYNC_DEBUG */
|
||||
ut_ad(block);
|
||||
|
||||
|
|
@ -939,6 +961,7 @@ buf_LRU_block_free_hashed_page(
|
|||
{
|
||||
#ifdef UNIV_SYNC_DEBUG
|
||||
ut_ad(mutex_own(&(buf_pool->mutex)));
|
||||
ut_ad(mutex_own(&block->mutex));
|
||||
#endif /* UNIV_SYNC_DEBUG */
|
||||
ut_a(block->state == BUF_BLOCK_REMOVE_HASH);
|
||||
|
||||
|
|
|
|||
|
|
@ -461,8 +461,8 @@ Gets the mutex number protecting the page record lock hash chain in the lock
|
|||
table. */
|
||||
UNIV_INLINE
|
||||
mutex_t*
|
||||
buf_frame_get_lock_mutex(
|
||||
/*=====================*/
|
||||
buf_frame_get_mutex(
|
||||
/*================*/
|
||||
/* out: mutex */
|
||||
byte* ptr); /* in: pointer to within a buffer frame */
|
||||
/***********************************************************************
|
||||
|
|
@ -713,7 +713,10 @@ struct buf_block_struct{
|
|||
|
||||
ulint magic_n; /* magic number to check */
|
||||
ulint state; /* state of the control block:
|
||||
BUF_BLOCK_NOT_USED, ... */
|
||||
BUF_BLOCK_NOT_USED, ...; changing
|
||||
this is only allowed when a thread
|
||||
has BOTH the buffer pool mutex AND
|
||||
block->mutex locked */
|
||||
byte* frame; /* pointer to buffer frame which
|
||||
is of size UNIV_PAGE_SIZE, and
|
||||
aligned to an address divisible by
|
||||
|
|
@ -731,8 +734,12 @@ struct buf_block_struct{
|
|||
ulint offset; /* page number within the space */
|
||||
ulint lock_hash_val; /* hashed value of the page address
|
||||
in the record lock hash table */
|
||||
mutex_t* lock_mutex; /* mutex protecting the chain in the
|
||||
record lock hash table */
|
||||
mutex_t mutex; /* mutex protecting this block:
|
||||
state (also protected by the buffer
|
||||
pool mutex), io_fix, buf_fix_count,
|
||||
and accessed; we introduce this new
|
||||
mutex in InnoDB-5.1 to relieve
|
||||
contention on the buffer pool mutex */
|
||||
rw_lock_t lock; /* read-write lock of the buffer
|
||||
frame */
|
||||
buf_block_t* hash; /* node used in chaining to the page
|
||||
|
|
@ -788,20 +795,27 @@ struct buf_block_struct{
|
|||
in heuristic algorithms, because of
|
||||
the possibility of a wrap-around! */
|
||||
ulint freed_page_clock;/* the value of freed_page_clock
|
||||
buffer pool when this block was
|
||||
last time put to the head of the
|
||||
LRU list */
|
||||
of the buffer pool when this block was
|
||||
the last time put to the head of the
|
||||
LRU list; a thread is allowed to
|
||||
read this for heuristic purposes
|
||||
without holding any mutex or latch */
|
||||
ibool old; /* TRUE if the block is in the old
|
||||
blocks in the LRU list */
|
||||
ibool accessed; /* TRUE if the page has been accessed
|
||||
while in the buffer pool: read-ahead
|
||||
may read in pages which have not been
|
||||
accessed yet */
|
||||
accessed yet; this is protected by
|
||||
block->mutex; a thread is allowed to
|
||||
read this for heuristic purposes
|
||||
without holding any mutex or latch */
|
||||
ulint buf_fix_count; /* count of how manyfold this block
|
||||
is currently bufferfixed */
|
||||
is currently bufferfixed; this is
|
||||
protected by block->mutex */
|
||||
ulint io_fix; /* if a read is pending to the frame,
|
||||
io_fix is BUF_IO_READ, in the case
|
||||
of a write BUF_IO_WRITE, otherwise 0 */
|
||||
of a write BUF_IO_WRITE, otherwise 0;
|
||||
this is protected by block->mutex */
|
||||
/* 4. Optimistic search field */
|
||||
|
||||
dulint modify_clock; /* this clock is incremented every
|
||||
|
|
@ -959,7 +973,9 @@ struct buf_pool_struct{
|
|||
number of buffer blocks removed from
|
||||
the end of the LRU list; NOTE that
|
||||
this counter may wrap around at 4
|
||||
billion! */
|
||||
billion! A thread is allowed to
|
||||
read this for heuristic purposes
|
||||
without holding any mutex or latch */
|
||||
ulint LRU_flush_ended;/* when an LRU flush ends for a page,
|
||||
this is incremented by one; this is
|
||||
set to zero when a buffer block is
|
||||
|
|
|
|||
|
|
@ -337,8 +337,8 @@ Gets the mutex number protecting the page record lock hash chain in the lock
|
|||
table. */
|
||||
UNIV_INLINE
|
||||
mutex_t*
|
||||
buf_frame_get_lock_mutex(
|
||||
/*=====================*/
|
||||
buf_frame_get_mutex(
|
||||
/*================*/
|
||||
/* out: mutex */
|
||||
byte* ptr) /* in: pointer to within a buffer frame */
|
||||
{
|
||||
|
|
@ -346,7 +346,7 @@ buf_frame_get_lock_mutex(
|
|||
|
||||
block = buf_block_align(ptr);
|
||||
|
||||
return(block->lock_mutex);
|
||||
return(&block->mutex);
|
||||
}
|
||||
|
||||
/*************************************************************************
|
||||
|
|
@ -519,6 +519,7 @@ buf_block_buf_fix_inc_debug(
|
|||
ret = rw_lock_s_lock_func_nowait(&(block->debug_latch), file, line);
|
||||
|
||||
ut_ad(ret == TRUE);
|
||||
ut_ad(mutex_own(&block->mutex));
|
||||
#endif
|
||||
block->buf_fix_count++;
|
||||
}
|
||||
|
|
@ -531,6 +532,9 @@ buf_block_buf_fix_inc(
|
|||
/*==================*/
|
||||
buf_block_t* block) /* in: block to bufferfix */
|
||||
{
|
||||
#ifdef UNIV_SYNC_DEBUG
|
||||
ut_ad(mutex_own(&block->mutex));
|
||||
#endif
|
||||
block->buf_fix_count++;
|
||||
}
|
||||
#endif /* UNIV_SYNC_DEBUG */
|
||||
|
|
@ -625,23 +629,24 @@ buf_page_release(
|
|||
|
||||
ut_ad(block);
|
||||
|
||||
mutex_enter_fast(&(buf_pool->mutex));
|
||||
|
||||
ut_a(block->state == BUF_BLOCK_FILE_PAGE);
|
||||
ut_a(block->buf_fix_count > 0);
|
||||
|
||||
if (rw_latch == RW_X_LATCH && mtr->modifications) {
|
||||
|
||||
mutex_enter(&buf_pool->mutex);
|
||||
buf_flush_note_modification(block, mtr);
|
||||
mutex_exit(&buf_pool->mutex);
|
||||
}
|
||||
|
||||
mutex_enter(&block->mutex);
|
||||
|
||||
#ifdef UNIV_SYNC_DEBUG
|
||||
rw_lock_s_unlock(&(block->debug_latch));
|
||||
#endif
|
||||
buf_fix_count = block->buf_fix_count;
|
||||
block->buf_fix_count = buf_fix_count - 1;
|
||||
|
||||
mutex_exit(&(buf_pool->mutex));
|
||||
mutex_exit(&block->mutex);
|
||||
|
||||
if (rw_latch == RW_S_LATCH) {
|
||||
rw_lock_s_unlock(&(block->lock));
|
||||
|
|
|
|||
Loading…
Add table
Reference in a new issue