· May want to check for alignment of your vm’s.  If you have virtual storage console installed, its under monitor/host config, and tools.  Check it out.

· Could be a reallocate issue if you have added a bunch of disks, but is doubtful. 

DFM is a used mostly for reporting among other things, but I use it primarily for reporting/protection manager, etc.  The Netapp Management Console is your friend.  That is the live view or a more “accurate” view of what is currently going on, with the ability to go back in time.  DFM is just going to show an average, and is not (IMHO) a good place to look for performance numbers..   Perfstat is the real ticket; that will show you console activity.

From: toasters-bounces@teaparty.net [mailto:toasters-bounces@teaparty.net] On Behalf Of Philbert Rupkins
Sent: Tuesday, May 21, 2013 2:19 PM
To: toasters@teaparty.net
Subject: VM Virtual Disk Latency Versus NFS Latency on Filer

Hello,

This may be more of a VMWare question.    From within Data Fabric Manager, I am seeing a spike in latency on a NetApp volume used as an NFS datastore.    DFM shows a spike in NFS latency of 50 ms on the volume.

However,  a virtual machine's performance counters in vSphere show a spike in Virtual Disk latency upwards of 700ms for the same "latency event".   

Any idea what might account for this difference in latency reporting between the NetApp (DFM) and ESXi?   I expected there to be some difference for obvious reasons but I didnt expect to see a difference of this magnitude.

Thanks,

Phil