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Distribute logical cpu amongst virtual machines
Distribute logical cpu amongst virtual machines
- Hello Im fairly new to hyper-v and i have some questions regarding cpu usage. I have a hyper-v machine with 2 quad core processors. I also have 3 virtual machines running on the server. 1 server is a production server and i want to give almost allresources to this one. In the hyper-v settings i can only set 4 processors(cores?) to the machine. Hwen i log in to this machine i see it runs with 4 cores (ctrl + alt + del). The other 2 machines are development machine witch will be scraped soon. I have set them to get 2 cpus each but the task manager only shows 1 core instead of 2.
Is there any way i can make the production server run on 6 cores or is 4 maximum? is 4 cores maximum for a VM, or have i got it all wrong?
I want to make sure that when i install other Hyper-v machines, these will run with optimal resources allocated to them.
Answers
- Four cores is the most you're going to be able to allocate to a Hyper-V virtual machine.
There is some confusion over this, but that's the limit. There have been changes to the maximum number of virtual processors supported for the overall Hyper-V server as well the maximum number of virtual machines supported. For example, this update http://www.microsoft.com/downloads/details.aspx?FamilyID=fe36823a-7e5a-4262-9bf5-d6b3ae3ad375&DisplayLang=en increases the maximum number of virtual processors from 16 to 24. Installing this update doesn't change the fact that you are still limited to allocating 4 virtual processors to a single virtual machine. Also, this update won't help you because you don't have that many physical cores in the first place.
You may be interested in using the Virtual Machine Reserve and Virtual Machine Limit settings described here: http://www.virtualizationadmin.com/articles-tutorials/microsoft-hyper-v-articles/load-balancing-high-availability/resource-allocation-hyper-v-part3.html. You could use the Virtual Machine Reserve to ensure that your production vm gets a specified minimum aamount of resources.- Proposed As Answer byDiego Castelli Friday, July 03, 2009 2:33 PM
- Marked As Answer byVincent HuMSFT, ModeratorMonday, July 06, 2009 9:56 AM
All Replies
- Four cores is the most you're going to be able to allocate to a Hyper-V virtual machine.
There is some confusion over this, but that's the limit. There have been changes to the maximum number of virtual processors supported for the overall Hyper-V server as well the maximum number of virtual machines supported. For example, this update http://www.microsoft.com/downloads/details.aspx?FamilyID=fe36823a-7e5a-4262-9bf5-d6b3ae3ad375&DisplayLang=en increases the maximum number of virtual processors from 16 to 24. Installing this update doesn't change the fact that you are still limited to allocating 4 virtual processors to a single virtual machine. Also, this update won't help you because you don't have that many physical cores in the first place.
You may be interested in using the Virtual Machine Reserve and Virtual Machine Limit settings described here: http://www.virtualizationadmin.com/articles-tutorials/microsoft-hyper-v-articles/load-balancing-high-availability/resource-allocation-hyper-v-part3.html. You could use the Virtual Machine Reserve to ensure that your production vm gets a specified minimum aamount of resources.- Proposed As Answer byDiego Castelli Friday, July 03, 2009 2:33 PM
- Marked As Answer byVincent HuMSFT, ModeratorMonday, July 06, 2009 9:56 AM
