Excessive Memory usage

I'm evaluating Percona XtraDB cluster in small 2 Node environment. Replication between nodes is working fine, but seems that even under light utilization mysqld process size grows all the time without releasing the memory compared to Standalone Server.

OS: Centos 6.3 x64

With following packages installed:

Percona-Server-shared-51-5.1.66-rel14.1.495.rhel6.x86_64
percona-release-0.0-1.x86_64
percona-xtrabackup-2.0.3-470.rhel6.x86_64
Percona-XtraDB-Cluster-client-5.5.27-23.6.356.rhel6.x86_64
Percona-XtraDB-Cluster-server-5.5.27-23.6.356.rhel6.x86_64

Updated Galera to the latest available:
galera-23.2.2-1.rhel5.x86_64

Node 1
my.cnf:

[mysqld_safe]
wsrep_urls=gcomm://10.0.0.101:4567,gcomm://10.0.0.102:4567,gcomm://

[mysqld]
datadir=/var/lib/mysql/mysql_data
user=mysql
log_slave_updates = 1
binlog_format=ROW
max_allowed_packet = 200M
default_storage_engine=InnoDB

#wsrep_provider=/usr/lib64/libgalera_smm.so
wsrep_provider=/usr/lib64/galera/libgalera_smm.so
wsrep_slave_threads=2
wsrep_cluster_name=mycluster
wsrep_sst_method=xtrabackup
wsrep_sst_auth=root:
wsrep_node_name=test-web01

innodb_locks_unsafe_for_binlog=1
innodb_autoinc_lock_mode=2
innodb_buffer_pool_size = 256M
innodb_additional_mem_pool_size = 4M
innodb_log_file_size = 64M
innodb_log_buffer_size = 8M
innodb_flush_method = O_DIRECT
innodb_flush_log_at_trx_commit = 1

Running following test:

create database ptest;
use ptest;
create table ti2(c1 int auto_increment primary key, c2 char(255)) engine=InnoDB;
insert into ti2(c2) values('abc');
insert into ti2(c2) select c2 from ti2;
insert into ti2(c2) select c2 from ti2;
insert into ti2(c2) select c2 from ti2;
insert into ti2(c2) select c2 from ti2;
insert into ti2(c2) select c2 from ti2;
insert into ti2(c2) select c2 from ti2;
insert into ti2(c2) select c2 from ti2;
insert into ti2(c2) select c2 from ti2;
insert into ti2(c2) select c2 from ti2;
insert into ti2(c2) select c2 from ti2;
insert into ti2(c2) select c2 from ti2;
insert into ti2(c2) select c2 from ti2;
insert into ti2(c2) select c2 from ti2;
insert into ti2(c2) select c2 from ti2;
insert into ti2(c2) select c2 from ti2;
insert into ti2(c2) select c2 from ti2;
insert into ti2(c2) select c2 from ti2;
insert into ti2(c2) select c2 from ti2;
insert into ti2(c2) select c2 from ti2;
insert into ti2(c2) select c2 from ti2;
insert into ti2(c2) select c2 from ti2;

Results of Percona-XtraDB-Cluster-server-5.5.27

  PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
  8951 mysql 20 0 1101m 83m 7160 S 0.0 5.1 0:00.29 mysqld

  PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
 8951 mysql 20 0 1741m 846m 2508 S 0.0 51.1 1:19.67 mysqld

Results of Percona-Server-server-55-5.5.28-rel29.1.335

  PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
 7077 mysql 20 0 756m 55m 5540 S 0.0 5.5 0:00.12 mysqld

  PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
 7077 mysql 20 0 756m 308m 5788 S 0.3 31.0 0:25.45 mysqld

When inserts are continued Galera cluster will eventually run out memory but with Standalone Server memory usage is not growing. Comparison is done against different Mysql versions, but I see similar result when I disable replication by removing wsrep parameters from XtraDB Cluster my.cnf.