VMware published an excellent document about VMFS volume management a few days ago.
VMware® VMFS Volume Management information guide
The guide explains the VMFS volume header metadata mechanism and describes the new 3.5 setting SCSI.CompareLUNNumber. A must read if you use third-party storage snapshot and replication technology.
 

I’m currently reviewing a design of a new virtual infrastructure. The VI uses multiple 10GB links to connect to a very large lefthand san.
I’m more a Fibre Channel guy, but I believe that this solution will smoke most mid-range FC-sans. I cannot wait to deploy the VI on the SAN.
But I need to get used [...]

When it comes to IO performance in the virtual infrastructure one of the most recommended “tweaks” is changing the Queue Depth (QD). But most forget that the QD parameter is just a small part of the IO path.
The IO path is made up of layers of hardware and software components, many of which can [...]