First off, make sure the values in nfsstat –d are actually incrementing significantly by  running nfsstat –z to clear the counters and then wait a while and looking at nfsstat –d again.

You may find that you are only doing a handful of unaligned ops and not hundreds or thousands per second.

--Jordan

From: toasters-bounces@teaparty.net [mailto:toasters-bounces@teaparty.net] On Behalf Of Will.Burchell@skanska.co.uk
Sent: Monday, June 16, 2014 2:50 PM
To: Toasters@teaparty.net
Subject: High CPU VM misalignment confusion

Hello. I am hoping you can guide me in the right direction

We have been experiencing very high CPU load on a 7-mode HA pair of 3270 controllers run 8.1.3P2

We have worked with netapp support on these issues and they note our workload is very high on one controller (where we run our VMware setup from)

We also have so called “bad practice” where we are running our exchange ISCSI LUNs on SATA with logs and dbs on the same aggregate (currently separating this out as I type)

I have been told by support we have VMDK misalignment, however I spent a long time a few months ago resolving this firstly by using the VSC tool to confirm the problem and then fixing it with a combination of MBRALIGN and VMware converter as a V2V process

The support guy tells me he seems misalignment when he runs nfsstat –d but MBRSCAN shows these are aligned. What is going on here?

Trying to reduce our CPU and IO burden but getting conflicting information.

Finally I think we should look to upgrade to 8.1.4P2 to remove some bugs? We would consider 8.2.x but I don’t think we can as we run Exchange 2010 (using SME 6.x etc)

Thanks in advance

William