> Yes i run it on a virtual machine don't know the exact hardware but it's shared among other idle servers.
> Using vmware vsphere And i think some intel xeon 3ghz processor a few GB ram and enough disk space.
I remember discussions in this forum where there were very poor performance was reported for DBMS under VMware. Some were very old, you'll have to run a search.
Here is a sample: http://moodle.org/mod/forum/discuss.php?d=146521