Sync optimistic_margine_count

buf/buf0buf.c

@@ -2850,7 +2850,7 @@ buf_page_create(
 	ibuf_merge_or_delete_for_page(NULL, space, offset, zip_size, TRUE);
 
 	/* Flush pages from the end of the LRU list if necessary */
-	buf_flush_free_margin();
+	buf_flush_free_margin(FALSE);
 
 	frame = block->frame;
 

buf/buf0flu.c

@@ -151,7 +151,7 @@ buf_flush_ready_for_replace(
 	buf_page_t*	bpage)	/* in: buffer control block, must be
 				buf_page_in_file(bpage) and in the LRU list */
 {
-	ut_ad(buf_pool_mutex_own());
+	//ut_ad(buf_pool_mutex_own());
 	ut_ad(mutex_own(buf_page_get_mutex(bpage)));
 	ut_ad(bpage->in_LRU_list);
 
@@ -162,6 +162,8 @@ buf_flush_ready_for_replace(
 		       && bpage->buf_fix_count == 0);
 	}
 
+	/* permited not to own LRU_mutex..  */
+/*
 	ut_print_timestamp(stderr);
 	fprintf(stderr,
 		"  InnoDB: Error: buffer block state %lu"
@@ -169,6 +171,7 @@ buf_flush_ready_for_replace(
 		(ulong) buf_page_get_state(bpage));
 	ut_print_buf(stderr, bpage, sizeof(buf_page_t));
 	putc('\n', stderr);
+*/
 
 	return(FALSE);
 }
@@ -1190,7 +1193,7 @@ buf_flush_LRU_recommendation(void)
 	ulint		n_replaceable;
 	ulint		distance	= 0;
 
-	buf_pool_mutex_enter();
+	//buf_pool_mutex_enter();
 
 	n_replaceable = UT_LIST_GET_LEN(buf_pool->free);
 
@@ -1216,7 +1219,7 @@ buf_flush_LRU_recommendation(void)
 		bpage = UT_LIST_GET_PREV(LRU, bpage);
 	}
 
-	buf_pool_mutex_exit();
+	//buf_pool_mutex_exit();
 
 	if (n_replaceable >= BUF_FLUSH_FREE_BLOCK_MARGIN) {
 
@@ -1235,8 +1238,9 @@ flush only pages such that the s-lock required for flushing can be acquired
 immediately, without waiting. */
 UNIV_INTERN
 void
-buf_flush_free_margin(void)
+buf_flush_free_margin(
 /*=======================*/
+	ibool	wait)
 {
 	ulint	n_to_flush;
 	ulint	n_flushed;
@@ -1245,7 +1249,7 @@ buf_flush_free_margin(void)
 
 	if (n_to_flush > 0) {
 		n_flushed = buf_flush_batch(BUF_FLUSH_LRU, n_to_flush, 0);
-		if (n_flushed == ULINT_UNDEFINED) {
+		if (wait && n_flushed == ULINT_UNDEFINED) {
 			/* There was an LRU type flush batch already running;
 			let us wait for it to end */
 

buf/buf0lru.c

@@ -885,7 +885,7 @@ buf_LRU_get_free_block(
 
 	/* No free block was found: try to flush the LRU list */
 
-	buf_flush_free_margin();
+	buf_flush_free_margin(TRUE);
 	++srv_buf_pool_wait_free;
 
 	os_aio_simulated_wake_handler_threads();

buf/buf0rea.c

@@ -358,7 +358,7 @@ buf_read_page(
 	}
 
 	/* Flush pages from the end of the LRU list if necessary */
-	buf_flush_free_margin();
+	buf_flush_free_margin(FALSE);
 
 	/* Increment number of I/O operations used for LRU policy. */
 	buf_LRU_stat_inc_io();
@@ -619,7 +619,7 @@ buf_read_ahead_linear(
 	os_aio_simulated_wake_handler_threads();
 
 	/* Flush pages from the end of the LRU list if necessary */
-	buf_flush_free_margin();
+	buf_flush_free_margin(FALSE);
 
 #ifdef UNIV_DEBUG
 	if (buf_debug_prints && (count > 0)) {
@@ -704,7 +704,7 @@ buf_read_ibuf_merge_pages(
 	os_aio_simulated_wake_handler_threads();
 
 	/* Flush pages from the end of the LRU list if necessary */
-	buf_flush_free_margin();
+	buf_flush_free_margin(FALSE);
 
 #ifdef UNIV_DEBUG
 	if (buf_debug_prints) {
@@ -789,7 +789,7 @@ buf_read_recv_pages(
 	os_aio_simulated_wake_handler_threads();
 
 	/* Flush pages from the end of the LRU list if necessary */
-	buf_flush_free_margin();
+	buf_flush_free_margin(FALSE);
 
 #ifdef UNIV_DEBUG
 	if (buf_debug_prints) {

handler/innodb_patch_info.h

@@ -27,5 +27,6 @@ struct innodb_enhancement {
 {"innodb_show_status","Improvements to SHOW INNODB STATUS","Memory information and lock info fixes","http://www.percona.com/docs/wiki/percona-innodb-plugin:innodb_show_status"},
 {"innodb_io","Improvements to InnoDB IO","","http://www.percona.com/docs/wiki/percona-innodb-plugin:innodb_io"},
 {"innodb_rw_lock","InnoDB RW-lock fixes","Useful for 8+ cores SMP systems","http://www.percona.com/docs/wiki/percona-innodb-plugin:innodb_rw_lock"},
+{"optimistic_margine_count","Fix of buffer_pool mutex","Decreases contention on buffer_pool mutex","http://www.percona.com/docs/wiki/percona-innodb-plugin:optimistic_margine_count"},
 {NULL, NULL, NULL, NULL}
 };

include/buf0flu.h

@@ -40,8 +40,9 @@ Flushes pages from the end of the LRU list if there is too small
 a margin of replaceable pages there. */
 UNIV_INTERN
 void
-buf_flush_free_margin(void);
+buf_flush_free_margin(
 /*=======================*/
+	ibool	wait);
 /************************************************************************
 Initializes a page for writing to the tablespace. */
 UNIV_INTERN