That's right. I blogged on it a bit here:
Share and enjoy!
Peter
From: Chris Muellner
[mailto:chris@northlandusa.com]
Sent: Friday, August 26, 2011 1:05 PM
To: Eugene Vilensky
Cc: toasters@teaparty.net
Subject: RE: Sources of unaligned IO other that Vmware? -
pw.over_limitpersists
“Will easily queryable stats about misaligned VMDKs on
NFS ever be available?”
It already is actually. Download the latest version of the
ESX Host Utility Kit and use the mbralign utility that’s included with it. It
can be run from either the VMware hosts themselves or from a Linux/Unix server
with mount access. If you take a NetApp snapshot of the datastore then you can
run the mbralign scan against the snapshotted -flat.vmdk(s) without having to
power off the virtual machines.
Also, some VMware align/misalignment statistics are included
in the output of nfsstat -d in version 7.3.5.1 or later. I may be slightly off
on the OnTap release version…
From:
toasters-bounces@teaparty.net [mailto:toasters-bounces@teaparty.net] On
Behalf Of Eugene Vilensky
Sent: Friday, August 26, 2011 2:39 PM
Cc: toasters@teaparty.net
Subject: Re: Sources of unaligned IO other that Vmware? - pw.over_limit
persists
On Fri, Aug 26, 2011 at 11:34 AM, Jeff Mohler <speedtoys.racing@gmail.com>
wrote:
"By the way, from ONTAP 8.0.1+, you
can directly check alignment with the “lun show –v” command:"
---
Gotta
be careful here, this only works on the -direct- lun.
This
will not tell you how healthy any underlying virtual filesystems within the LUN
may or may not be, only the high level direct LUN itself.
Will easily queryable stats about misaligned VMDKs on NFS
ever be available? Without mounting the datastores on Linux and checking with
fdisk...