Sorry, I'm not aware of any formal document on the issue. However from my benchmark the I/O is 7/8 time slower than on a similar configuration with a HP BL20p (with 1 CPU). I used the same identical version of SLES9 (SP2) and oracle (10gR2). Datafiles were on ASM (we tried even ext3). The storage used for VMWARE ESX is on HP EVA 5000 (tested even on EVA 3000 and IBM ESS 800 shark). Regards Fabrizio ________________________________ From: Stauffer, Robert G [mailto:rstauffer@xxxxxxxxxxxxxxxxxxxx] Sent: 05 December, 2005 5:07 PM To: Magni Fabrizio; HELMUT.DAIMINGER@xxxxxx; oracle-l@xxxxxxxxxxxxx Subject: RE: Is anybody running 10g on VMWare? We're beginning to use VMWare here, but haven't put any Oracle databases on it yet. Because I'm new to VMWare, this is the first I've heard about any database performance issues. Are these issues formally documented or discussed anywhere that you could share with me? Thanks.