This is the first of a series of HOL posts about "how we did it".
For the primary workload, we used the vCenter Virtual Appliance using the local Postgres database.
Due to the unusually high churn rate of HOL, we need to have a high ratio of vCenters. These vCenters needed to have a lot of horsepower behind them to survive this churn.
1) Paravirtualized SCSI adaptors for disk controllers for the VCVA vm.
2) Created 2 additional dedicated datastores (Luns) for each of the DB & Logs on the VCVA vm.
3) 4 CPU's x 32GB memory (we might have gone a bit high on memory)
4) Removed all long term logging and rollups, we are doing all stats in vC Ops.
5) Increased heap sizes to large for the SPS, tomcat inventory & vCenter process.
The only downside to the VCVA is the fact that it doesn't support linked mode, but you can get around that with the NGC & SSO. http://www.virtuallyghetto.com/2012/09/automatically-join-multiple-vcsa-51.html