Merge lp:~gl-az/percona-server/5.5-1018264 into lp:percona-server/5.5

[George Ormond Lorch III]

Fix for PS bug lp:1018264 - Multiple hash index partitions causes overly
large hash index: When multiple adaptive hash index partitions are
specified, _each_ partition was being created with hash_size which should
be 1/64 of the total size of all buffer pools which is incorrect and can
cause overly high memory usage. hash_size should be representing the
_total_ size of all partitions, not the individual size of each partition.
Modfied code to divide hash_size in btr_search_sys_create by number of
partitions (btr_search_index_num).

Fix for PS bug lp:1018264 - Multiple hash index partitions causes overly
large hash index: When multiple adaptive hash index partitions are
specified, _each_ partition was being created with hash_size which should
be 1/64 of the total size of all buffer pools which is incorrect and can
cause overly high memory usage. hash_size should be representing the
_total_ size of all partitions, not the individual size of each partition.
Modfied code to divide hash_size in btr_search_sys_create by number of
partitions (btr_search_index_num).

http://jenkins.percona.com/view/PS%205.5/job/percona-server-5.5-param/521/

[Stewart Smith (stewart)]

review: Approve

=== modified file 'Percona-Server/storage/innobase/btr/btr0sea.c'
--- Percona-Server/storage/innobase/btr/btr0sea.c	2012-05-10 07:49:14 +0000
+++ Percona-Server/storage/innobase/btr/btr0sea.c	2012-09-28 02:18:22 +0000
@@ -183,6 +183,15 @@
 	//rw_lock_create(btr_search_latch_key, &btr_search_latch,
 	//	       SYNC_SEARCH_SYS);
 
+	/* PS bug lp:1018264 - Multiple hash index partitions causes overly
+	   large hash index: When multiple adaptive hash index partitions are
+	   specified, _each_ partition was being created with hash_size which
+	   should be 1/64 of the total size of all buffer pools which is
+	   incorrect and can cause overly high memory usage. hash_size
+	   should be representing the _total_ size of all partitions, not the
+	   individual size of each partition. */
+	hash_size /= btr_search_index_num;
+
 	btr_search_sys = mem_alloc(sizeof(btr_search_sys_t));
 
 	/* btr_search_index_num should be <= 32. (bits of trx->has_search_latch) */