Comments on: Hyper-Threading on vSphere

By: RTFM Education » Blog Archive » vNews – April 14th, 2010

RTFM Education » Blog Archive » vNews – April 14th, 2010 — Wed, 14 Apr 2010 18:04:16 +0000

[...] Hyper-threading is back [...]

By: Hyper-Threading on vSphere « vFrank

Hyper-Threading on vSphere « vFrank — Tue, 30 Mar 2010 07:33:42 +0000

[...] of my favorite bloggers and performance guru Scott Drummonds has posted some info on Hyper-Threading and [...]

By: Marius Redelinghuys

Marius Redelinghuys — Fri, 19 Mar 2010 06:44:03 +0000

Hi Scott,

My bad, I have not seen that section yet.

Thanx for the info and link.

By: Scott

Scott — Thu, 18 Mar 2010 15:43:37 +0000

Marius,

As I suggested above, it seems that HT provides a universal good. We recommend leaving it on.

Why do you think that HT should not be used with FT? Certainly they are compatible:

http://kb.vmware.com/kb/1013428

By: Marius Redelinghuys

Marius Redelinghuys — Thu, 18 Mar 2010 07:23:54 +0000

Why should it recommended that HT be enabled? Should you do any FT then HT should be switched off in any case. Although it is always nice to see plenty of CPU’s (with HT), it might just cause obstacles in future

By: vSphere 4.0, Hyper-Threading, and Terminal Services « Pivot Point

vSphere 4.0, Hyper-Threading, and Terminal Services « Pivot Point — Wed, 17 Mar 2010 22:23:34 +0000

[...] intel, scheduler, terminal services, vsphere — Scott @ 3:23 pm I recently wrote a blog article detailing Hyper-Threading (HT) and its effect on vSphere. An astute reader pointed out, a recent update to Project VRC’s terminal services analysis [...]

By: Hyperthreading and vSphere 4 w/ Nehalem and Westmere « Virtualization Buster

Mon, 08 Mar 2010 23:21:50 +0000

[...] http://vpivot.com/2010/03/06/hyper-threading-on-vsphere/ [...]

By: orz

orz — Mon, 08 Mar 2010 21:12:41 +0000

Thanks for the follow up, Scott. Great to hear you guys are already on it, wouldn’t have expected any less.

Now I just hope your findings on this and more general performance insights on here are soon to be publicized, in the awesome fashion as usual.

By: Scott

Scott — Mon, 08 Mar 2010 16:35:00 +0000

orz,

Yeah, I am aware of that work. We researched the reason for the disappointing results and discovered something interesting about our scheduler. I wrote up a summary that was distributed internally. I think that I will share those comments on this blog.

The interesting thing about those VRC results is that ESX did not benefit from HT the way it should. HT did not slow things down but nor did it provide value (on vSphere).

More to come…

Scott

By: Comparing Nehalem and Harpertown running vSphere in a production environment « A glimpse into the life of IT

Mon, 08 Mar 2010 00:43:57 +0000

[...] Unlike the old E5430 hosts, hyper threading is possible on the x5550 hosts, and according to VMWare’s documentation, is recommended. Whether it actually improves performance is subject to some debate, as found here. [...]