Debian Configuration :: Xen4 On Squeeze - Slow Mysql In DomU

I have a mysql server in guest domU on debian squeeze. when i create test table and do INSERT INTO test (name, value) VALUES(RAND(), RAND()); Query OK, 1 row affected (0.28 sec)

At other physical server with same configuration Query OK, 1 row affected (0.00 sec)

I try this several time but on physical server max value never get over 0.05sec and on VM lowest value was 0.13sec.

Another tests:

On physical server:

OLTP test statistics:

Threads fairness:

on VM:

OLTP test statistics:

Threads fairness:

performance of disk write speed on VM is much better then on physical server .