[libvirt-users] CPU Resource Reservation using KVM
Hi All I am new to KVM world. I have been using VMware for about a year. In VMware world we can reserve cpu resources for a VM. Say for instance if we need 4 vCPUs with a total of 8000 GHz then we can mention this configuration in vCenter while creating a VM. This guarantees 8000 GHz of cpu resources for the deployed VM. How can i achieve the same thing using KVM ? Please provide as much details as possible. Any pointers for reading this would also be helpful. Appreciate your responses in this regard. Thanks Jatin
On Mon, Apr 13, 2015 at 12:14:12PM +0530, Jatin Davey wrote:
Hi All
I am new to KVM world. I have been using VMware for about a year.
In VMware world we can reserve cpu resources for a VM. Say for instance if we need 4 vCPUs with a total of 8000 GHz then we can mention this configuration in vCenter while creating a VM. This guarantees 8000 GHz of cpu resources for the deployed VM.
How can i achieve the same thing using KVM ?
If you are comfortable with command line, you can look at `virsh` manual page for setvcpus - change number of virtual CPUs to control how many vCPUs you can allocate. If you're using `virt-manager`, you should be able to control it via UI for a guest under its "Show virtual hardware details" and look for "Processor". -- /kashyap
On 4/13/2015 1:18 PM, Kashyap Chamarthy wrote:
On Mon, Apr 13, 2015 at 12:14:12PM +0530, Jatin Davey wrote:
Hi All
I am new to KVM world. I have been using VMware for about a year.
In VMware world we can reserve cpu resources for a VM. Say for instance if we need 4 vCPUs with a total of 8000 GHz then we can mention this configuration in vCenter while creating a VM. This guarantees 8000 GHz of cpu resources for the deployed VM.
How can i achieve the same thing using KVM ?
If you are comfortable with command line, you can look at `virsh` manual page for
setvcpus - change number of virtual CPUs
to control how many vCPUs you can allocate.
If you're using `virt-manager`, you should be able to control it via UI for a guest under its "Show virtual hardware details" and look for "Processor".
I have looked at virsh and more specifically "setvcpus". We can assign virtual CPUs using it but my question is different. I am looking at reserving cpu speed to the virtual cpu's. I know we can allocate and modify the amount vcpu's using setvcpus command but how can i ask kvm to reserve a particular amount of cpu speed of the host core's to the virtual cpus. Thanks Jatin
On Mon, Apr 13, 2015 at 01:41:59PM +0530, Jatin Davey wrote:
On 4/13/2015 1:18 PM, Kashyap Chamarthy wrote:
Hi All
I am new to KVM world. I have been using VMware for about a year.
In VMware world we can reserve cpu resources for a VM. Say for instance if we need 4 vCPUs with a total of 8000 GHz then we can mention this configuration in vCenter while creating a VM. This guarantees 8000 GHz of cpu resources for the deployed VM.
How can i achieve the same thing using KVM ? If you are comfortable with command line, you can look at `virsh` manual
On Mon, Apr 13, 2015 at 12:14:12PM +0530, Jatin Davey wrote: page for
setvcpus - change number of virtual CPUs
to control how many vCPUs you can allocate.
If you're using `virt-manager`, you should be able to control it via UI for a guest under its "Show virtual hardware details" and look for "Processor".
I have looked at virsh and more specifically "setvcpus".
You mention that info only now.
We can assign virtual CPUs using it but my question is different. I am looking at reserving cpu speed to the virtual cpu's. I know we can allocate and modify the amount vcpu's using setvcpus command but how can i ask kvm to reserve a particular amount of cpu speed of the host core's to the virtual cpus.
Okay. I don't notice an option to regulate CPU freq. But the closest I see is the 'quota' XML attribute (as part of 'cputune' element) that will "ensure that all vcpus run at the same speed." https://libvirt.org/formatdomain.html#elementsCPUTuning -- /kashyap
On 4/13/2015 2:19 PM, Kashyap Chamarthy wrote:
On Mon, Apr 13, 2015 at 01:41:59PM +0530, Jatin Davey wrote:
On 4/13/2015 1:18 PM, Kashyap Chamarthy wrote:
Hi All
I am new to KVM world. I have been using VMware for about a year.
In VMware world we can reserve cpu resources for a VM. Say for instance if we need 4 vCPUs with a total of 8000 GHz then we can mention this configuration in vCenter while creating a VM. This guarantees 8000 GHz of cpu resources for the deployed VM.
How can i achieve the same thing using KVM ? If you are comfortable with command line, you can look at `virsh` manual
On Mon, Apr 13, 2015 at 12:14:12PM +0530, Jatin Davey wrote: page for
setvcpus - change number of virtual CPUs
to control how many vCPUs you can allocate.
If you're using `virt-manager`, you should be able to control it via UI for a guest under its "Show virtual hardware details" and look for "Processor".
I have looked at virsh and more specifically "setvcpus". You mention that info only now.
We can assign virtual CPUs using it but my question is different. I am looking at reserving cpu speed to the virtual cpu's. I know we can allocate and modify the amount vcpu's using setvcpus command but how can i ask kvm to reserve a particular amount of cpu speed of the host core's to the virtual cpus. Okay. I don't notice an option to regulate CPU freq. But the closest I see is the 'quota' XML attribute (as part of 'cputune' element) that will "ensure that all vcpus run at the same speed."
Yes , The information provided in this link is what precisely i wanted to know. Thanks for pointing to it. Thanks Jatin
participants (2)
-
Jatin Davey -
Kashyap Chamarthy