And here are several links to help you out tune it up!
With identical hardware, there is a small performance overhead due to virtualization, but that goes away if you consolidate to new hardware which is the case in 90% of a consolidation projects.
Overhead of virtualization was a constant and due to the increasing power of processors this constant is now irrelevant.
As any new SQL implementation, you need to follow some basic rules to tune up SQL.
Storage, a place you can get a lot of performance increase following simple rules.
· 15K disk gives you an average of +33% of disk speed compared to 10K ones.
· Disk alignment gives you another +10% to +15% (read this MS KB for an how-to)
· NTFS Allocation Unit Size of 64KB (SQL best practice)
· RAID-5 is best choice for databases t hat are >75% of reads
· Split databases and logs on different disks
· More spindles better performances
At the data center we have virtualized several SQL 2005 servers, even clustered them in active/active mode. We found the solution very stable whilst given us the benefits of virtualization and most of the add-on features such snapshots and HA.
A good thought, if you’re using VMware DRS, put it manual mode for any guest that has RDM disk attached. Anyway they can’t be vmotionned due to RDM SCSI bus sharing conflict and eventually DRS may try to migrate the guest causing some troubles especially to clusters.
Happy database virtualization!