Comments on: Storage: How to size your LUNs?

By: Awais

Awais — Wed, 30 Nov 2011 18:47:00 +0000

size ki samajh nai aye

By: - Cliff Davies

- Cliff Davies — Wed, 01 Jun 2011 20:50:20 +0000

[...] on this subject. A few that I personally recommend are this, this, this (Appendix C) this and this. And you might be thinking…why is this guy recommending older VMW and EMC whitepapers? The first [...]

By: Sizing your ESX LUNs « VMware geekery and Microsoft trickery

Sizing your ESX LUNs « VMware geekery and Microsoft trickery — Tue, 15 Feb 2011 08:37:40 +0000

[...] http://www.gabesvirtualworld.com/?p=68 http://searchvmware.techtarget.com/tip/0,289483,sid179_gci1350469,00.html http://communities.vmware.com/thread/104211 http://communities.vmware.com/thread/238199 http://www.yellow-bricks.com/2009/06/23/vmfslun-size/ [...]

By: VMware LUN Sizes « Virtualised Reality

VMware LUN Sizes « Virtualised Reality — Sun, 03 May 2009 19:44:26 +0000

[...] http://www.gabesvirtualworld.com/?p=68 [...]

By: Robert

Robert — Sun, 29 Mar 2009 12:47:15 +0000

Gabe,

I have been using 1 lun per 1 datastore and everything seems to be running great. Do you see any real problems with doing this. Also, what have you seen in array size on the SAN. Do you see anything wrong with creating very large arrays and storing very small LUNs on each array. Are there any best practices you care to mention?

Thank you

By: Virtualization Short Take #10 - blog.scottlowe.org - The weblog of an IT pro specializing in virtualization, storage, and servers

Thu, 26 Jun 2008 14:47:29 +0000

[...] from the VC database. That’s handy. In an earlier article, Gabe also weighed in on storage sizing as well. This seems to be getting quite a bit of attention recently (gee, I can’t imagine [...]

By: Nick

Nick — Thu, 12 Jun 2008 14:14:19 +0000

I can’t see how IOPS wouldn’t be a major issue with this, unless you’re running RAID groups with many spindles to give high IOPS capacity.

As a worst case if you did a 3 x 1TB disk RAID-5 RAID group and ran 30 VMs on it you’ve got 30 servers contending for about 400 IOPS. Of course SAN cache performance etc alleviate this but surely there’d still be a major bottleneck.

By: Martin Steadman

Martin Steadman — Fri, 06 Jun 2008 22:55:07 +0000

In my experience, you run into cluster filesystem locking problems long before you run out of IOPs on a good storage device.

I keep the lock contention at bay by limiting the number of VMs per VMFS to 25-30. With 30GB VMs, this works out to 750 – 900 GB per LUN.

Our onsite VMware TAM and our EMC storage reps actually recommend less, for busy VMs: 450 – 500 GB per LUN, with one VMFS per target.

Our VMs are never all active at the the same time, so we can get away with a higher density.

By: Vikash Kumar Roy

Vikash Kumar Roy — Wed, 28 May 2008 13:44:07 +0000

My experience with lun sizing depends upon your queue depth at the SP and at the FC. If you have set the queue depth to low and you are trying to oversubscribe this you will have potential performance problem. We uses standard lun size of 400GB and just ensure that we do not oversubscribe the queue depth and we have more than 30+ VMDK files on it. So as you mention earlier there is no thumb rule for lun size to determine and I have to agree with that.

By: Andrew Storrs

Andrew Storrs — Thu, 22 May 2008 23:12:09 +0000