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I've been using ESXi 5.0 quite successfully with my datastore provided by NFS share on FreeNAS 8. All of a sudden i'm experiencing terrible performance.

I've ruled out some things:

Hardware (FreeNAS side): Transferring the same data using samba is fine Hardware (ESXi side): Same problem from both ESXi hypervisors and the problem goes away when i connect to an NFS datastore sitting on my WHS2011 box

I can't see anything that stands out in any of the logs on either the FreeNAS box or the ESXi box.

Watching the performance graph against the datastore within vSphere i can see that the write latency is 2000+ (2seconds+) while trying to boot a windows server 2008 r2 virtual machine.

How can i further diagnose/troubleshoot this problem?

EDIT one extra note- i'm not sure if this can help pinpoint the problem... while powering on the virtual machines they sit at 95% for a quite a while.

EDIT copying from the nfs share to my macbook pro i get about 10MB/sec- which is pretty poor although I think my problem is less throughput, but more latency.

This image shows the latency against my 2 datastores (ufs resides on the FreeNAS server and vm on the WHS2011 server). Both have the same load (i am running the windows server 2008 r2 installation and it's at about 10% complete)



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You do know FreeNAS isn't supported with vSphere v5 right? –  Chopper3 Jan 30 '12 at 14:22
@Chopper3 yes- appreciate that. But I (and many others) have had it running AOK up till now so i'm puzzled. –  Lee Tickett Jan 30 '12 at 14:35
So what was the problem / solution to this. Or did you just reboot? –  Brent Aug 2 '12 at 8:17
never got a solution unfortunately –  Lee Tickett Aug 4 '12 at 19:45

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