path: root/percona/5.0.91-b22-20100522/innodb_dict_size_limit.patch

diff -ruN a/innobase/btr/btr0sea.c b/innobase/btr/btr0sea.c
--- a/innobase/btr/btr0sea.c	2009-08-27 18:42:17.000000000 +0900
+++ b/innobase/btr/btr0sea.c	2009-08-27 18:43:11.000000000 +0900
@@ -1077,6 +1077,124 @@
 }
 
 /************************************************************************
+Drops a page hash index based on index */
+
+void
+btr_search_drop_page_hash_index_on_index(
+/*=====================================*/
+	dict_index_t*	index)		/* in: record descriptor */
+{
+	page_t*		page;
+	hash_table_t*	table;
+	buf_block_t*	block;
+	ulint		n_fields;
+	ulint		n_bytes;
+	rec_t*		rec;
+	ulint		fold;
+	ulint		prev_fold;
+	dulint		tree_id;
+	ulint		n_cached;
+	ulint		n_recs;
+	ulint*		folds;
+	ulint		i;
+	mem_heap_t*	heap	= NULL;
+	ulint*		offsets;
+
+	rw_lock_x_lock(&btr_search_latch);
+	mutex_enter(&buf_pool->mutex);
+
+	table = btr_search_sys->hash_index;
+
+	block = UT_LIST_GET_LAST(buf_pool->LRU);
+
+	while (block != NULL) {
+		if (block->index == index && block->is_hashed) {
+			page = block->frame;
+
+			/* from btr_search_drop_page_hash_index() */
+			n_fields = block->curr_n_fields;
+			n_bytes = block->curr_n_bytes;
+
+			ut_a(n_fields + n_bytes > 0);
+
+			n_recs = page_get_n_recs(page);
+
+			/* Calculate and cache fold values into an array for fast deletion
+			from the hash index */
+
+			folds = mem_alloc(n_recs * sizeof(ulint));
+
+			n_cached = 0;
+
+			rec = page_get_infimum_rec(page);
+			rec = page_rec_get_next(rec);
+
+			tree_id = btr_page_get_index_id(page);
+	
+			ut_a(0 == ut_dulint_cmp(tree_id, index->id));
+
+			prev_fold = 0;
+
+			offsets = NULL;
+
+			while (!page_rec_is_supremum(rec)) {
+				/* FIXME: in a mixed tree, not all records may have enough
+				ordering fields: */
+				offsets = rec_get_offsets(rec, index, offsets,
+							n_fields + (n_bytes > 0), &heap);
+				ut_a(rec_offs_n_fields(offsets) == n_fields + (n_bytes > 0));
+				fold = rec_fold(rec, offsets, n_fields, n_bytes, tree_id);
+
+				if (fold == prev_fold && prev_fold != 0) {
+
+					goto next_rec;
+				}
+
+				/* Remove all hash nodes pointing to this page from the
+				hash chain */
+
+				folds[n_cached] = fold;
+				n_cached++;
+next_rec:
+				rec = page_rec_get_next(rec);
+				prev_fold = fold;
+			}
+
+			for (i = 0; i < n_cached; i++) {
+
+				ha_remove_all_nodes_to_page(table, folds[i], page);
+			}
+
+			ut_a(index->search_info->ref_count > 0);
+			index->search_info->ref_count--;
+
+			block->is_hashed = FALSE;
+			block->index = NULL;
+	
+			if (UNIV_UNLIKELY(block->n_pointers)) {
+				/* Corruption */
+				ut_print_timestamp(stderr);
+				fprintf(stderr,
+"  InnoDB: Corruption of adaptive hash index. After dropping\n"
+"InnoDB: the hash index to a page of %s, still %lu hash nodes remain.\n",
+					index->name, (ulong) block->n_pointers);
+			}
+
+			mem_free(folds);
+		}
+
+		block = UT_LIST_GET_PREV(LRU, block);
+	}
+
+	mutex_exit(&buf_pool->mutex);
+	rw_lock_x_unlock(&btr_search_latch);
+
+	if (UNIV_LIKELY_NULL(heap)) {
+		mem_heap_free(heap);
+	}
+}
+
+/************************************************************************
 Drops a page hash index when a page is freed from a fseg to the file system.
 Drops possible hash index if the page happens to be in the buffer pool. */
 
diff -ruN a/innobase/dict/dict0boot.c b/innobase/dict/dict0boot.c
--- a/innobase/dict/dict0boot.c	2009-07-07 21:53:58.000000000 +0900
+++ b/innobase/dict/dict0boot.c	2009-08-27 18:42:59.000000000 +0900
@@ -247,6 +247,7 @@
 	system tables */
 	/*-------------------------*/
 	table = dict_mem_table_create("SYS_TABLES", DICT_HDR_SPACE, 8, FALSE);
+	table->n_mysql_handles_opened = 1; /* for pin */
 
 	dict_mem_table_add_col(table, "NAME", DATA_BINARY, 0, 0, 0);
 	dict_mem_table_add_col(table, "ID", DATA_BINARY, 0, 0, 0);
@@ -283,6 +284,7 @@
 	ut_a(success);
 	/*-------------------------*/
 	table = dict_mem_table_create("SYS_COLUMNS", DICT_HDR_SPACE, 7, FALSE);
+	table->n_mysql_handles_opened = 1; /* for pin */
 
 	dict_mem_table_add_col(table, "TABLE_ID", DATA_BINARY,0,0,0);
 	dict_mem_table_add_col(table, "POS", DATA_INT, 0, 4, 0);
@@ -309,6 +311,7 @@
 	ut_a(success);
 	/*-------------------------*/
 	table = dict_mem_table_create("SYS_INDEXES", DICT_HDR_SPACE, 7, FALSE);
+	table->n_mysql_handles_opened = 1; /* for pin */
 
 	dict_mem_table_add_col(table, "TABLE_ID", DATA_BINARY, 0,0,0);
 	dict_mem_table_add_col(table, "ID", DATA_BINARY, 0, 0, 0);
@@ -345,6 +348,7 @@
 	ut_a(success);
 	/*-------------------------*/
 	table = dict_mem_table_create("SYS_FIELDS", DICT_HDR_SPACE, 3, FALSE);
+	table->n_mysql_handles_opened = 1; /* for pin */
 
 	dict_mem_table_add_col(table, "INDEX_ID", DATA_BINARY, 0,0,0);
 	dict_mem_table_add_col(table, "POS", DATA_INT, 0, 4, 0);
diff -ruN a/innobase/dict/dict0crea.c b/innobase/dict/dict0crea.c
--- a/innobase/dict/dict0crea.c	2009-07-07 21:53:58.000000000 +0900
+++ b/innobase/dict/dict0crea.c	2009-08-27 18:42:59.000000000 +0900
@@ -1178,6 +1178,9 @@
             	/* Foreign constraint system tables have already been
             	created, and they are ok */
 
+		table1->n_mysql_handles_opened = 1; /* for pin */
+		table2->n_mysql_handles_opened = 1; /* for pin */
+
 		mutex_exit(&(dict_sys->mutex));
 
             	return(DB_SUCCESS);
@@ -1267,6 +1270,11 @@
 	
 	trx->op_info = "";
 
+	table1 = dict_table_get_low("SYS_FOREIGN");
+	table2 = dict_table_get_low("SYS_FOREIGN_COLS");
+	table1->n_mysql_handles_opened = 1; /* for pin */
+	table2->n_mysql_handles_opened = 1; /* for pin */
+
 	row_mysql_unlock_data_dictionary(trx);
 
   	trx_free_for_mysql(trx);
diff -ruN a/innobase/dict/dict0dict.c b/innobase/dict/dict0dict.c
--- a/innobase/dict/dict0dict.c	2009-07-07 21:53:58.000000000 +0900
+++ b/innobase/dict/dict0dict.c	2009-08-27 18:43:11.000000000 +0900
@@ -638,6 +638,8 @@
 	mutex_enter(&(dict_sys->mutex));
 
 	table = dict_table_get_on_id_low(table_id, trx);
+
+	dict_table_LRU_trim(table);
 	
 	mutex_exit(&(dict_sys->mutex));
 
@@ -752,6 +754,8 @@
 	
 	table = dict_table_get_low(table_name);
 
+	dict_table_LRU_trim(table);
+
 	mutex_exit(&(dict_sys->mutex));
 
 	if (table != NULL) {
@@ -787,6 +791,8 @@
 	        table->n_mysql_handles_opened++;
 	}
 
+	dict_table_LRU_trim(table);
+
 	mutex_exit(&(dict_sys->mutex));
 
 	if (table != NULL) {
@@ -1267,20 +1273,64 @@
 too much space. Currently not used! */
 
 void
-dict_table_LRU_trim(void)
-/*=====================*/
+dict_table_LRU_trim(
+/*================*/
+	dict_table_t*	self)
 {
 	dict_table_t*	table;
 	dict_table_t*	prev_table;
+	dict_foreign_t*	foreign;
+	ulint		n_removed;
+	ulint		n_have_parent;
+	ulint		cached_foreign_tables;
 
-	ut_error;
+	//ut_error;
 
 #ifdef UNIV_SYNC_DEBUG
 	ut_ad(mutex_own(&(dict_sys->mutex)));
 #endif /* UNIV_SYNC_DEBUG */
 
+retry:
+	n_removed = n_have_parent = 0;
 	table = UT_LIST_GET_LAST(dict_sys->table_LRU);
 
+	while ( srv_dict_size_limit && table
+		&& ((dict_sys->table_hash->n_cells
+		     + dict_sys->table_id_hash->n_cells
+		     + dict_sys->col_hash->n_cells) * sizeof(hash_cell_t)
+		    + dict_sys->size) > srv_dict_size_limit ) {
+		prev_table = UT_LIST_GET_PREV(table_LRU, table);
+
+		if (table == self || table->n_mysql_handles_opened)
+			goto next_loop;
+
+		cached_foreign_tables = 0;
+		foreign = UT_LIST_GET_FIRST(table->foreign_list);
+		while (foreign != NULL) {
+			if (foreign->referenced_table)
+				cached_foreign_tables++;
+			foreign = UT_LIST_GET_NEXT(foreign_list, foreign);
+		}
+
+		/* TODO: use table->mem_fix also, if it becomes exact. */
+
+		if (cached_foreign_tables == 0) {
+			dict_table_remove_from_cache(table);
+			n_removed++;
+		} else {
+			n_have_parent++;
+		}
+next_loop:
+		table = prev_table;
+	}
+
+	if ( srv_dict_size_limit && n_have_parent && n_removed
+		&& ((dict_sys->table_hash->n_cells
+		     + dict_sys->table_id_hash->n_cells
+		     + dict_sys->col_hash->n_cells) * sizeof(hash_cell_t)
+		    + dict_sys->size) > srv_dict_size_limit )
+		goto retry;
+/*
 	while (table && (dict_sys->size >
 			 buf_pool_get_max_size() / DICT_POOL_PER_VARYING)) {
 
@@ -1292,6 +1342,7 @@
 
 		table = prev_table;
 	}
+*/
 }
 
 /**************************************************************************
@@ -1565,6 +1616,10 @@
 #ifdef UNIV_SYNC_DEBUG
 	ut_ad(mutex_own(&(dict_sys->mutex)));
 #endif /* UNIV_SYNC_DEBUG */
+	/* remove all entry of the index from adaptive hash index,
+	because removing from adaptive hash index needs dict_index */
+	if (srv_use_adaptive_hash_indexes && srv_dict_size_limit)
+		btr_search_drop_page_hash_index_on_index(index);
 
 	/* We always create search info whether or not adaptive
 	hash index is enabled or not. */
diff -ruN a/innobase/ibuf/ibuf0ibuf.c b/innobase/ibuf/ibuf0ibuf.c
--- a/innobase/ibuf/ibuf0ibuf.c	2009-08-27 18:42:17.000000000 +0900
+++ b/innobase/ibuf/ibuf0ibuf.c	2009-08-27 18:42:59.000000000 +0900
@@ -535,6 +535,7 @@
 	sprintf(buf, "SYS_IBUF_TABLE_%lu", (ulong) space);
 	/* use old-style record format for the insert buffer */
 	table = dict_mem_table_create(buf, space, 2, FALSE);
+	table->n_mysql_handles_opened = 1; /* for pin */
 
 	dict_mem_table_add_col(table, "PAGE_NO", DATA_BINARY, 0, 0, 0);
 	dict_mem_table_add_col(table, "TYPES", DATA_BINARY, 0, 0, 0);
diff -ruN a/innobase/include/btr0sea.h b/innobase/include/btr0sea.h
--- a/innobase/include/btr0sea.h	2009-07-07 21:54:00.000000000 +0900
+++ b/innobase/include/btr0sea.h	2009-08-27 18:43:11.000000000 +0900
@@ -97,6 +97,13 @@
 /*============================*/
 	page_t*	page);	/* in: index page, s- or x-latched */
 /************************************************************************
+Drops a page hash index based on index */
+
+void
+btr_search_drop_page_hash_index_on_index(
+/*=====================================*/
+	dict_index_t*	index);		/* in: record descriptor */
+/************************************************************************
 Drops a page hash index when a page is freed from a fseg to the file system.
 Drops possible hash index if the page happens to be in the buffer pool. */
 
diff -ruN a/innobase/include/dict0dict.h b/innobase/include/dict0dict.h
--- a/innobase/include/dict0dict.h	2009-07-07 21:54:01.000000000 +0900
+++ b/innobase/include/dict0dict.h	2009-08-27 18:42:59.000000000 +0900
@@ -938,6 +938,11 @@
 	const char*	ptr,	/* in: scan from */
 	const char*	string);/* in: look for this */
 
+void
+dict_table_LRU_trim(
+/*================*/
+	dict_table_t*	self);
+
 /* Buffers for storing detailed information about the latest foreign key
 and unique key errors */
 extern FILE*	dict_foreign_err_file;
diff -ruN a/innobase/include/dict0dict.ic b/innobase/include/dict0dict.ic
--- a/innobase/include/dict0dict.ic	2009-07-07 21:54:01.000000000 +0900
+++ b/innobase/include/dict0dict.ic	2009-08-27 18:42:59.000000000 +0900
@@ -533,6 +533,13 @@
 
 	HASH_SEARCH(name_hash, dict_sys->table_hash, table_fold, table,
 				ut_strcmp(table->name, table_name) == 0);
+
+	/* make young in table_LRU */
+	if (table) {
+		UT_LIST_REMOVE(table_LRU, dict_sys->table_LRU, table);
+		UT_LIST_ADD_FIRST(table_LRU, dict_sys->table_LRU, table);
+	}
+
 	return(table);
 }
 
@@ -592,6 +599,10 @@
 	if (table != NULL) {
 		table->mem_fix++;
 
+		/* make young in table_LRU */
+		UT_LIST_REMOVE(table_LRU, dict_sys->table_LRU, table);
+		UT_LIST_ADD_FIRST(table_LRU, dict_sys->table_LRU, table);
+
 		/* lock_push(trx, table, LOCK_DICT_MEM_FIX) */
 	}
 	
diff -ruN a/innobase/include/srv0srv.h b/innobase/include/srv0srv.h
--- a/innobase/include/srv0srv.h	2009-08-27 18:42:17.000000000 +0900
+++ b/innobase/include/srv0srv.h	2009-08-27 18:42:59.000000000 +0900
@@ -147,6 +147,8 @@
 extern uint	srv_read_ahead;
 extern uint	srv_adaptive_checkpoint;
 
+extern ulint	srv_dict_size_limit;
+
 extern volatile ibool srv_io_pattern;
 extern ulong	srv_io_pattern_trace;
 extern ulong	srv_io_pattern_trace_running;
@@ -552,6 +554,7 @@
         ulint innodb_data_writes;
         ulint innodb_data_written;
         ulint innodb_data_reads;
+        ulint innodb_dict_tables;
         ulint innodb_buffer_pool_pages_total;
         ulint innodb_buffer_pool_pages_data;
         ulint innodb_buffer_pool_pages_dirty;
diff -ruN a/innobase/srv/srv0srv.c b/innobase/srv/srv0srv.c
--- a/innobase/srv/srv0srv.c	2009-08-27 18:42:17.000000000 +0900
+++ b/innobase/srv/srv0srv.c	2009-08-27 18:42:59.000000000 +0900
@@ -353,6 +353,8 @@
 uint	srv_read_ahead = 3; /* 1: random  2: linear  3: Both */
 uint	srv_adaptive_checkpoint = 0; /* 0: none  1: reflex  2: estimate */
 
+ulint	srv_dict_size_limit = 0;
+
 volatile ibool srv_io_pattern = FALSE;
 ulint   srv_io_pattern_trace = 0;
 ulint   srv_io_pattern_trace_running = 0;
@@ -1953,6 +1955,7 @@
         export_vars.innodb_data_reads= os_n_file_reads;
         export_vars.innodb_data_writes= os_n_file_writes;
         export_vars.innodb_data_written= srv_data_written;
+        export_vars.innodb_dict_tables= (dict_sys ? UT_LIST_GET_LEN(dict_sys->table_LRU) : 0);
         export_vars.innodb_buffer_pool_read_requests= buf_pool->n_page_gets;
         export_vars.innodb_buffer_pool_write_requests= srv_buf_pool_write_requests;
         export_vars.innodb_buffer_pool_wait_free= srv_buf_pool_wait_free;
diff -ruN a/mysql-test/r/innodb_dict_size_limit.result b/mysql-test/r/innodb_dict_size_limit.result
--- /dev/null	1970-01-01 09:00:00.000000000 +0900
+++ b/mysql-test/r/innodb_dict_size_limit.result	2009-08-27 18:42:59.000000000 +0900
@@ -0,0 +1,60 @@
+DROP TABLE IF EXISTS `test_5`;
+DROP TABLE IF EXISTS `test_4`;
+DROP TABLE IF EXISTS `test_3`;
+DROP TABLE IF EXISTS `test_2`;
+DROP TABLE IF EXISTS `test_1`;
+SET storage_engine=InnoDB;
+SET GLOBAL innodb_dict_size_limit=1;
+FLUSH TABLES;
+CREATE TABLE `test_1` (`a` int, `b` int, PRIMARY KEY  (`a`));
+CREATE TABLE `test_2` (`a` int, `b` int, PRIMARY KEY  (`a`));
+CREATE TABLE `test_3` (`a` int, `b` int, PRIMARY KEY  (`a`));
+CREATE TABLE `test_4` (`a` int, `b` int, PRIMARY KEY  (`a`));
+CREATE TABLE `test_5` (`a` int, `b` int, PRIMARY KEY  (`a`));
+ALTER TABLE `test_5` ADD CONSTRAINT FOREIGN KEY(`b`) REFERENCES `test_4`(`a`);
+ALTER TABLE `test_4` ADD CONSTRAINT FOREIGN KEY(`b`) REFERENCES `test_3`(`a`);
+SHOW GLOBAL STATUS LIKE 'Innodb_dict_tables';
+Variable_name	Value
+Innodb_dict_tables	9
+FLUSH TABLES;
+SELECT * FROM `test_1`;
+a	b
+SHOW GLOBAL STATUS LIKE 'Innodb_dict_tables';
+Variable_name	Value
+Innodb_dict_tables	8
+SELECT * FROM `test_3`;
+a	b
+SHOW GLOBAL STATUS LIKE 'Innodb_dict_tables';
+Variable_name	Value
+Innodb_dict_tables	11
+FLUSH TABLES;
+SELECT * FROM `test_2`;
+a	b
+SHOW GLOBAL STATUS LIKE 'Innodb_dict_tables';
+Variable_name	Value
+Innodb_dict_tables	8
+SELECT * FROM `test_1`;
+a	b
+FLUSH TABLES;
+SELECT * FROM `test_4`;
+a	b
+SHOW GLOBAL STATUS LIKE 'Innodb_dict_tables';
+Variable_name	Value
+Innodb_dict_tables	9
+SELECT * FROM `test_3`;
+a	b
+SHOW GLOBAL STATUS LIKE 'Innodb_dict_tables';
+Variable_name	Value
+Innodb_dict_tables	10
+SET GLOBAL innodb_dict_size_limit=0;
+FLUSH TABLES;
+SELECT * FROM `test_2`;
+a	b
+SHOW GLOBAL STATUS LIKE 'Innodb_dict_tables';
+Variable_name	Value
+Innodb_dict_tables	11
+DROP TABLE `test_5`;
+DROP TABLE `test_4`;
+DROP TABLE `test_3`;
+DROP TABLE `test_2`;
+DROP TABLE `test_1`;
diff -ruN a/mysql-test/t/innodb_dict_size_limit.test b/mysql-test/t/innodb_dict_size_limit.test
--- /dev/null	1970-01-01 09:00:00.000000000 +0900
+++ b/mysql-test/t/innodb_dict_size_limit.test	2009-08-27 18:42:59.000000000 +0900
@@ -0,0 +1,63 @@
+#
+# Test for new variable innodb_dict_size_limit;
+#
+-- source include/have_innodb.inc
+
+--disable_warnings
+DROP TABLE IF EXISTS `test_5`;
+DROP TABLE IF EXISTS `test_4`;
+DROP TABLE IF EXISTS `test_3`;
+DROP TABLE IF EXISTS `test_2`;
+DROP TABLE IF EXISTS `test_1`;
+--enable_warnings
+
+SET storage_engine=InnoDB;
+SET GLOBAL innodb_dict_size_limit=1;
+
+FLUSH TABLES;
+
+CREATE TABLE `test_1` (`a` int, `b` int, PRIMARY KEY  (`a`));
+CREATE TABLE `test_2` (`a` int, `b` int, PRIMARY KEY  (`a`));
+CREATE TABLE `test_3` (`a` int, `b` int, PRIMARY KEY  (`a`));
+CREATE TABLE `test_4` (`a` int, `b` int, PRIMARY KEY  (`a`));
+CREATE TABLE `test_5` (`a` int, `b` int, PRIMARY KEY  (`a`));
+
+ALTER TABLE `test_5` ADD CONSTRAINT FOREIGN KEY(`b`) REFERENCES `test_4`(`a`);
+ALTER TABLE `test_4` ADD CONSTRAINT FOREIGN KEY(`b`) REFERENCES `test_3`(`a`);
+
+SHOW GLOBAL STATUS LIKE 'Innodb_dict_tables';
+
+FLUSH TABLES;
+SELECT * FROM `test_1`;
+
+SHOW GLOBAL STATUS LIKE 'Innodb_dict_tables';
+
+SELECT * FROM `test_3`;
+
+SHOW GLOBAL STATUS LIKE 'Innodb_dict_tables';
+
+FLUSH TABLES;
+SELECT * FROM `test_2`;
+
+SHOW GLOBAL STATUS LIKE 'Innodb_dict_tables';
+
+SELECT * FROM `test_1`;
+FLUSH TABLES;
+SELECT * FROM `test_4`;
+SHOW GLOBAL STATUS LIKE 'Innodb_dict_tables';
+
+SELECT * FROM `test_3`;
+SHOW GLOBAL STATUS LIKE 'Innodb_dict_tables';
+
+SET GLOBAL innodb_dict_size_limit=0;
+FLUSH TABLES;
+SELECT * FROM `test_2`;
+
+SHOW GLOBAL STATUS LIKE 'Innodb_dict_tables';
+
+DROP TABLE `test_5`;
+DROP TABLE `test_4`;
+DROP TABLE `test_3`;
+DROP TABLE `test_2`;
+DROP TABLE `test_1`;
+
diff -ruN a/patch_info/innodb_dict_size_limit.info b/patch_info/innodb_dict_size_limit.info
--- /dev/null	1970-01-01 09:00:00.000000000 +0900
+++ b/patch_info/innodb_dict_size_limit.info	2009-08-27 18:42:59.000000000 +0900
@@ -0,0 +1,9 @@
+File=innodb_dict_size_limit.patch
+Name=Limit dictionary cache size
+Version=1.0
+Author=Percona
+License=GPL
+Comment=Variable innodb_dict_size_limit in bytes
+ChangeLog=
+2009-01-26
+YK: Initial release
diff -ruN a/sql/ha_innodb.cc b/sql/ha_innodb.cc
--- a/sql/ha_innodb.cc	2009-08-27 18:42:17.000000000 +0900
+++ b/sql/ha_innodb.cc	2009-08-27 18:42:59.000000000 +0900
@@ -288,6 +288,8 @@
   (char*) &export_vars.innodb_dblwr_pages_written,        SHOW_LONG},
   {"dblwr_writes",
   (char*) &export_vars.innodb_dblwr_writes,               SHOW_LONG},
+  {"dict_tables",
+  (char*) &export_vars.innodb_dict_tables,                SHOW_LONG},
   {"log_waits",
   (char*) &export_vars.innodb_log_waits,                  SHOW_LONG},
   {"log_write_requests",
diff -ruN a/sql/ha_innodb.h b/sql/ha_innodb.h
--- a/sql/ha_innodb.h	2009-08-27 18:42:17.000000000 +0900
+++ b/sql/ha_innodb.h	2009-08-27 18:42:59.000000000 +0900
@@ -243,6 +243,7 @@
 extern ulong srv_enable_unsafe_group_commit;
 extern uint srv_read_ahead;
 extern uint srv_adaptive_checkpoint;
+extern ulong srv_dict_size_limit;
 extern ulong srv_show_locks_held;
 extern ulong srv_show_verbose_locks;
 extern ulong srv_io_pattern_trace;
diff -ruN a/sql/mysqld.cc b/sql/mysqld.cc
--- a/sql/mysqld.cc	2009-08-27 18:42:17.000000000 +0900
+++ b/sql/mysqld.cc	2009-08-27 18:42:59.000000000 +0900
@@ -5101,6 +5101,7 @@
   OPT_INNODB_ADAPTIVE_CHECKPOINT,
   OPT_INNODB_READ_IO_THREADS,
   OPT_INNODB_WRITE_IO_THREADS,
+  OPT_INNODB_DICT_SIZE_LIMIT,
   OPT_INNODB_ADAPTIVE_HASH_INDEX,
   OPT_FEDERATED,
   OPT_INNODB_USE_LEGACY_CARDINALITY_ALGORITHM
@@ -5464,6 +5465,10 @@
    "Number of background write I/O threads in InnoDB.",
    (gptr*) &innobase_write_io_threads, (gptr*) &innobase_write_io_threads,
    0, GET_LONG, REQUIRED_ARG, 8, 1, 64, 0, 0, 0},
+  {"innodb_dict_size_limit", OPT_INNODB_DICT_SIZE_LIMIT,
+   "Limit the allocated memory for dictionary cache. (0: unlimited)",
+   (gptr*) &srv_dict_size_limit, (gptr*) &srv_dict_size_limit, 0,
+   GET_ULONG, REQUIRED_ARG, 0, 0, ULONG_MAX, 0, 0 ,0},
   {"innodb_io_pattern_trace", OPT_INNODB_IO_PATTERN_TRACE,
    "Create/Drop the internal hash table for IO pattern tracing.",
    (gptr*) &srv_io_pattern_trace, (gptr*) &srv_io_pattern_trace,
diff -ruN a/sql/set_var.cc b/sql/set_var.cc
--- a/sql/set_var.cc	2009-08-27 18:42:17.000000000 +0900
+++ b/sql/set_var.cc	2009-08-27 18:42:59.000000000 +0900
@@ -540,6 +540,8 @@
 sys_var_enum	sys_innodb_adaptive_checkpoint("innodb_adaptive_checkpoint",
                            &srv_adaptive_checkpoint,
                            &innodb_adaptive_checkpoint_typelib, fix_innodb_adaptive_checkpoint);
+sys_var_long_ptr	sys_innodb_dict_size_limit("innodb_dict_size_limit",
+                                                   &srv_dict_size_limit);
 sys_var_long_ptr  sys_innodb_show_locks_held(
                                         "innodb_show_locks_held",
                                         &srv_show_locks_held);
@@ -930,6 +932,7 @@
   &sys_innodb_read_ahead,
   &sys_innodb_enable_unsafe_group_commit,
   &sys_innodb_adaptive_checkpoint,
+  &sys_innodb_dict_size_limit,
   &sys_innodb_show_locks_held,
   &sys_innodb_show_verbose_locks,
   &sys_innodb_io_pattern_trace,
@@ -1084,6 +1087,7 @@
   {sys_innodb_adaptive_checkpoint.name, (char*) &sys_innodb_adaptive_checkpoint, SHOW_SYS},
   {"innodb_read_io_threads", (char*) &innobase_read_io_threads, SHOW_LONG},
   {"innodb_write_io_threads", (char*) &innobase_write_io_threads, SHOW_LONG},
+  {sys_innodb_dict_size_limit.name, (char*) &sys_innodb_dict_size_limit, SHOW_SYS},
   {sys_innodb_io_pattern_trace.name, (char*) &sys_innodb_io_pattern_trace, SHOW_SYS},
   {sys_innodb_io_pattern_trace_running.name, (char*) &sys_innodb_io_pattern_trace_running, SHOW_SYS},
   {sys_innodb_io_pattern_size_limit.name, (char*) &sys_innodb_io_pattern_size_limit, SHOW_SYS},