Comments on: vSphere 4.0, Hyper-Threading, and Terminal Services http://vpivot.com/2010/03/17/vsphere-4-0-hyper-threading-and-terminal-services/ Scott Drummonds on Virtualization Wed, 08 Feb 2012 14:30:44 +0000 hourly 1 http://wordpress.org/?v=3.2.1 By: Duane Smith http://vpivot.com/2010/03/17/vsphere-4-0-hyper-threading-and-terminal-services/comment-page-1/#comment-1299 Duane Smith Wed, 30 Jun 2010 18:36:57 +0000 http://vpivot.com/?p=333#comment-1299 I see you said for condition 3 "A roughly one-to-one mapping between vCPUs and logical processors.". Logical Processsors clears it up. Thanks! This is good stuff. I see you said for condition 3 “A roughly one-to-one mapping between vCPUs and logical processors.”. Logical Processsors clears it up. Thanks! This is good stuff.

]]> By: Duane Smith http://vpivot.com/2010/03/17/vsphere-4-0-hyper-threading-and-terminal-services/comment-page-1/#comment-1297 Duane Smith Wed, 30 Jun 2010 17:50:53 +0000 http://vpivot.com/?p=333#comment-1297 I'm not clear on the requirement and hoping you can help. 4, four-way VMs would be a total of 16 vcpus. So for the specific condition to be met, you would have to be on a host with 4 Xeon 5500s? Do they exist? Or does the one-to-one mapping requirement apply to threads, in which case the 4ea. @ 4 VCPU VMs would meet the requirement on the 2 socket Xeon 5500. I’m not clear on the requirement and hoping you can help. 4, four-way VMs would be a total of 16 vcpus. So for the specific condition to be met, you would have to be on a host with 4 Xeon 5500s? Do they exist? Or does the one-to-one mapping requirement apply to threads, in which case the 4ea. @ 4 VCPU VMs would meet the requirement on the 2 socket Xeon 5500.

]]> By: drummonds http://vpivot.com/2010/03/17/vsphere-4-0-hyper-threading-and-terminal-services/comment-page-1/#comment-954 drummonds Sun, 16 May 2010 23:54:39 +0000 http://vpivot.com/?p=333#comment-954 Yes. The patch was released and documented in <a href="http://kb.vmware.com/kb/1020233" rel="nofollow">KB article 1020233</a>. The patch actually makes no modification to ESX behavior at all. Is simply opens up the possibility of a special scheduler configuration. That special scheduler configuration should be utilized when the condition described by the KB occurs. Yes. The patch was released and documented in KB article 1020233. The patch actually makes no modification to ESX behavior at all. Is simply opens up the possibility of a special scheduler configuration. That special scheduler configuration should be utilized when the condition described by the KB occurs.

]]> By: Alan Osborne http://vpivot.com/2010/03/17/vsphere-4-0-hyper-threading-and-terminal-services/comment-page-1/#comment-951 Alan Osborne Sun, 16 May 2010 21:56:12 +0000 http://vpivot.com/?p=333#comment-951 Has the patch been released to the public yet? If so, is there any down-side to installing the patch? Has the patch been released to the public yet?

If so, is there any down-side to installing the patch?

]]> By: IT Bubble : VMware patch for vSphere 4 validates 3rd party benchmarks http://vpivot.com/2010/03/17/vsphere-4-0-hyper-threading-and-terminal-services/comment-page-1/#comment-646 IT Bubble : VMware patch for vSphere 4 validates 3rd party benchmarks Thu, 15 Apr 2010 15:03:43 +0000 http://vpivot.com/?p=333#comment-646 [...] Intel Nehalem processors when Hyper-Threading is enabled, the good folk at VMware have rushed out a patch. To quote:'It took us some time to understand the reason for these results, but we eventually [...] [...] Intel Nehalem processors when Hyper-Threading is enabled, the good folk at VMware have rushed out a patch. To quote:'It took us some time to understand the reason for these results, but we eventually [...]

]]> By: VMware releases ESX patch to improve performance | Virtualization Spotlight http://vpivot.com/2010/03/17/vsphere-4-0-hyper-threading-and-terminal-services/comment-page-1/#comment-637 VMware releases ESX patch to improve performance | Virtualization Spotlight Fri, 02 Apr 2010 12:15:23 +0000 http://vpivot.com/?p=333#comment-637 [...] few weeks ago VMware acknowledged a bug in ESX that translates into poor performance when it runs Microsoft Terminal Services workload on Intel [...] [...] few weeks ago VMware acknowledged a bug in ESX that translates into poor performance when it runs Microsoft Terminal Services workload on Intel [...]

]]> By: Scott http://vpivot.com/2010/03/17/vsphere-4-0-hyper-threading-and-terminal-services/comment-page-1/#comment-636 Scott Wed, 24 Mar 2010 20:18:19 +0000 http://vpivot.com/?p=333#comment-636 If the vCPU-to-core ratio is greater than one, the scheduler is always able to find work to plug into the available scheduler slots. Even idle VMs fill a small amount of CPU. So, we are not seeing this issue with any large number of VMs. If the vCPU-to-core ratio is greater than one, the scheduler is always able to find work to plug into the available scheduler slots. Even idle VMs fill a small amount of CPU. So, we are not seeing this issue with any large number of VMs.

]]> By: Andrew Fidel http://vpivot.com/2010/03/17/vsphere-4-0-hyper-threading-and-terminal-services/comment-page-1/#comment-635 Andrew Fidel Wed, 24 Mar 2010 18:09:50 +0000 http://vpivot.com/?p=333#comment-635 Scott, Wouldn't having 4 very busy 4-way VM's on a 5500 with additional idle VM's cause the same issue? Or is this really a very corner case where the lack of a tiebreaker input from the idle VM's throws off the scheduler? Scott,
Wouldn’t having 4 very busy 4-way VM’s on a 5500 with additional idle VM’s cause the same issue? Or is this really a very corner case where the lack of a tiebreaker input from the idle VM’s throws off the scheduler?

]]> By: Kimmo http://vpivot.com/2010/03/17/vsphere-4-0-hyper-threading-and-terminal-services/comment-page-1/#comment-634 Kimmo Tue, 23 Mar 2010 00:31:44 +0000 http://vpivot.com/?p=333#comment-634 Thanks Scott Thanks Scott

]]> By: Scott http://vpivot.com/2010/03/17/vsphere-4-0-hyper-threading-and-terminal-services/comment-page-1/#comment-633 Scott Mon, 22 Mar 2010 17:53:56 +0000 http://vpivot.com/?p=333#comment-633 Kimmo, If your production environment meets the three requirements, you may benefit from the patch we are going to release. Using 4-way VMs on any Xeon 5500 processor, meeting requirement three means having only four VMs on the host. It is uncommon for our customers to run so few VMs on a Xeon 5500 system. Scott Kimmo,

If your production environment meets the three requirements, you may benefit from the patch we are going to release. Using 4-way VMs on any Xeon 5500 processor, meeting requirement three means having only four VMs on the host. It is uncommon for our customers to run so few VMs on a Xeon 5500 system.

Scott

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