Hyper-V and Hyper-threading: On or off?

Posted by CapBBeard on Server Fault See other posts from Server Fault or by CapBBeard
Published on 2009-07-29T04:41:53Z Indexed on 2010/04/10 6:43 UTC
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hyperthreading

Hey all,

With the new Xeon CPUs supporting Hyper-threading, what is the current wisdom with regard to using it (or not) on a Hyper-V host machine?

I was originally under the impression that turning it on in a virtual host environment could be detrimental as the 'extra' CPUs were not true cores. However I've also read (unconfirmed) comments along the lines of MS doing some hard work to get Hyper-V running well in a Hyper-threading environment.

Does anyone have any solid information or experience in this regard? Cheers!

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