From the Punching Cloud blog

Over the course of past week I was asked a couple of storage related questions in regards to VMFS volumes and LUN partitions. The topic of the questions were based on something that folks with experience, and knowledge of VMware virtualization platforms are aware about. The questions were focused VMFS volumes and how they work, and the reason as why is not a good practice to create multiple VMFS volumes in a LUN that has been partitioned.  I wanted to take a moment and try to explain it as simple as I can so here is my take on why we don’t want to use multiple VMFS volumes per LUN.  [..]