I got a vmware esxi 5.5 on a Dell PowerEdge R710 with 6 sata disks in RAID5 with a single logical volume on a Perc H700 controller. Vmware is installed on this Raid5 volume and also the virtual machines run on the same volume.
I noticed that when I try some storage benchmark on vm I got a good read/write throughput (100-150 MB/s), but I have an high latency and in general I noticed that vm aren't fast as I'm expect (the server has 2 Quad core Xeon CPU with 48 GB or ram).
I always read comments about vmware best practices which recommend to not run vm on the same datastore where vmware is installed, I also read about some caching issue about that (vmware disable caching on its installation volume), but I never found any detailed information about this on vmware knowledge base (except generic guidelines, something like 'this is not the best practice' without any technical explanation).
Do you have some tecnical informations about that or have you found something more specific about this behavior?
Do you think this latency (and in general this clumsy performance) can be solved creating a new volume on the same controller (ora a single disk on the same controller outside the RAID array) and installing vmware on that volume or disk?
Thanks for any information