From e2c305f32b39ee4dc9cf003f2e078366ce7a70f3 Mon Sep 17 00:00:00 2001
From: marko <Unknown>
Date: Wed, 15 Nov 2006 21:49:14 +0000
Subject: [PATCH] branches/zip: Improve the shrinking of the buffer pool.
buf_LRU_block_free_non_file_page(): Deallocate block->page_zip.data
to avoid ut_a(!block->page_zip.data) in buf_chunk_free().
buf_chunk_free(): Add the assertion ut_a(!block->in_LRU_list).
buf_pool_resize(): When shrinking the buffer pool and there are
non-free blocks in the candidate chunk, free the clean blocks
and move the dirty blocks to the end of the LRU list and request a flush.
Proceed if the chunk becomes free, and retry otherwise.
---
buf/buf0buf.c | 81 ++++++++++++++++++++++++++++++++++++++++++++++-----
buf/buf0lru.c | 8 ++++-
2 files changed, 80 insertions(+), 9 deletions(-)
diff --git a/buf/buf0buf.c b/buf/buf0buf.c
index 25ad81505e4..cf68b9156c0 100644
--- a/buf/buf0buf.c
+++ b/buf/buf0buf.c
@@ -798,6 +798,7 @@ buf_chunk_free(
ut_a(block->state == BUF_BLOCK_NOT_USED);
ut_a(!block->page_zip.data);
+ ut_a(!block->in_LRU_list);
/* Remove the block from the free list. */
ut_a(block->in_free_list);
UT_LIST_REMOVE(free, buf_pool->free, block);
@@ -904,6 +905,7 @@ buf_pool_resize(void)
buf_chunk_t* chunks;
buf_chunk_t* chunk;
+try_again:
mutex_enter(&buf_pool->mutex);
if (srv_buf_pool_old_size == srv_buf_pool_size) {
@@ -919,7 +921,9 @@ buf_pool_resize(void)
= (srv_buf_pool_curr_size - srv_buf_pool_size)
/ UNIV_PAGE_SIZE;
ulint max_size;
+ ulint max_free_size;
buf_chunk_t* max_chunk;
+ buf_chunk_t* max_free_chunk;
shrink_again:
if (buf_pool->n_chunks <= 1) {
@@ -932,25 +936,86 @@ buf_pool_resize(void)
not larger than the size difference */
chunks = buf_pool->chunks;
chunk = chunks + buf_pool->n_chunks;
- max_size = 0;
- max_chunk = NULL;
+ max_size = max_free_size = 0;
+ max_chunk = max_free_chunk = NULL;
while (--chunk >= chunks) {
if (chunk->size <= chunk_size
- && chunk->size > max_size
- && buf_chunk_all_free(chunk)) {
- max_size = chunk->size;
- max_chunk = chunk;
+ && chunk->size > max_free_size) {
+ if (chunk->size > max_size) {
+ max_size = chunk->size;
+ max_chunk = chunk;
+ }
+
+ if (buf_chunk_all_free(chunk)) {
+ max_free_size = chunk->size;
+ max_free_chunk = chunk;
+ }
}
}
- if (!max_size) {
+ if (!max_free_size) {
+
+ ulint dirty = 0;
+ ulint nonfree = 0;
+ buf_block_t* block;
+ buf_block_t* bend;
/* Cannot shrink: try again later
(do not assign srv_buf_pool_old_size) */
- goto func_exit;
+ if (!max_chunk) {
+
+ goto func_exit;
+ }
+
+ block = max_chunk->blocks;
+ bend = block + max_chunk->size;
+
+ /* Move the blocks of chunk to the end of the
+ LRU list and try to flush them. */
+ for (; block < bend; block++) {
+ if (block->state != BUF_BLOCK_FILE_PAGE) {
+
+ continue;
+ }
+
+ mutex_enter(&block->mutex);
+
+ if (!buf_flush_ready_for_replace(block)) {
+
+ buf_LRU_make_block_old(block);
+ dirty++;
+ } else if (!buf_LRU_free_block(block)) {
+ nonfree++;
+ }
+
+ mutex_exit(&block->mutex);
+ }
+
+ /* See if the chunk was in fact free. */
+ if (!dirty && !nonfree) {
+
+ goto is_free;
+ }
+
+ mutex_exit(&buf_pool->mutex);
+
+ /* Request for a flush of the chunk. */
+ if (buf_flush_batch(BUF_FLUSH_LRU, dirty,
+ ut_dulint_zero)
+ == ULINT_UNDEFINED) {
+
+ buf_flush_wait_batch_end(BUF_FLUSH_LRU);
+ }
+
+ /* Retry after flushing. */
+ goto try_again;
}
+ max_size = max_free_size;
+ max_chunk = max_free_chunk;
+
+is_free:
srv_buf_pool_old_size = srv_buf_pool_size;
/* Rewrite buf_pool->chunks. Copy everything but max_chunk. */
diff --git a/buf/buf0lru.c b/buf/buf0lru.c
index 461dd752c3c..a5db248f585 100644
--- a/buf/buf0lru.c
+++ b/buf/buf0lru.c
@@ -868,12 +868,18 @@ buf_LRU_block_free_non_file_page(
#ifdef UNIV_DEBUG
/* Wipe contents of page to reveal possible stale pointers to it */
memset(block->frame, '\0', UNIV_PAGE_SIZE);
- memset(block->page_zip.data, 0xff, block->page_zip.size);
#else
/* Wipe page_no and space_id */
memset(block->frame + FIL_PAGE_OFFSET, 0xfe, 4);
memset(block->frame + FIL_PAGE_ARCH_LOG_NO_OR_SPACE_ID, 0xfe, 4);
#endif
+ if (block->page_zip.data) {
+ /* TODO: return zip to an aligned pool */
+ ut_free(block->page_zip.data);
+ block->page_zip.data = NULL;
+ block->page_zip.size = 0;
+ }
+
UT_LIST_ADD_FIRST(free, buf_pool->free, block);
block->in_free_list = TRUE;
--
2.30.9