VMWARE ESX Server slow write when using NFS as a Data-Store. April 4, 2008

I’ve been playing around with virtualization for quite sometime not, at the beginning I wasn’t too interested. In fact a friend of mine, Q hooked on this thing like a junkie on crack…heh…. need less to say, I’ve been testing HA, DRS and Vmotion stuff out.

To have all your VMs accessible to your esx servers at any time, you would need a common storage amongst them, the Data Store is this case.

Any of you tested with NFS, would notice because of the sync being done when writing a file to the nfs store, dramatic decrease in throughput for the data, can result in VMs crashing and sometimes in Windows, disk errors show up in the event log.

I currently run Centos 5 (latest update)

/VMWARE-HOSTS x.x.x.x(rw,async,no_subtree_check,nohide,no_root_squash) x.x.x.x(rw,async,no_subtree_check,nohide,no_root_squash)
I was reaching throughput of 9 – 16 mbit with sync, using async throughput has increased.

Now I get more than 80mbit.