At 05/17/2012 02:06 PM, KAMEZAWA Hiroyuki Wrote:
> (2012/05/17 15:05), Wen Congyang wrote:
>
>> At 05/17/2012 01:42 PM, Hu Tao Wrote:
>>> On Thu, May 17, 2012 at 01:25:48PM +0800, Wen Congyang wrote:
>>>> At 05/17/2012 01:09 PM, KAMEZAWA Hiroyuki Wrote:
>>>>> (2012/05/17 14:07), Wen Congyang wrote:
>>>>>
>>>>>> At 05/17/2012 12:46 PM, KAMEZAWA Hiroyuki Wrote:
>>>>>>> (2012/05/17 12:54), Wen Congyang wrote:
>>>>>
>>>>>>>> So, if we donot limit the hypervisor, the behavior shoule not be
>>>>>>>> changed. So we should limit the whole vm. If the hypervisor threads
>>>>>>>> are limited, there is no need to limit the whole vm.
>>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>> need to tune hypervisor quota to limit vcpu-only quota ?
>>>>>>> Sounds strange to me.
>>>>>>
>>>>>> No, current implemetion is:
>>>>>> 1. limit vcpu and hypervisor: vm is not limited
>>>>>> 2. limit vcpu only: vm is limited
>>>>>> 3. limit hypervisor: vm is not limited
>>>>>> 4. vcpu and hypervisor are not limited: vm is not limited.
>>>>>>
>>>>>
>>>>>
>>>>> In 2.
>>>>>
>>>>> vm ----- quota_is_limited
>>>>> |- hypervisor ----- quota is unlimited
>>>>> |- vcpu[0...x] ----- quota is limited
>>>>>
>>>>> Hm...vm is limited. It seems user need to tune vm's quota...can user
>>>>> makes vm's quota to be unlimited and limit *only* vpcus as Xen ?
>>>>
>>>> Without this patchset, the vm will be limited if the vcpu is limited.
>>>> We cannot know whether the hypervisor is unlimited or the user does not
>>>> set it. If the user does not set it, we should not change the behavior.
>>>> So I donot find an easy way to limit only vcpus.
>>>
>>> Can we change the implementation like these:
>>>
>>> 1.
>>> <cputune>
>>> <vcpu>
>>> <period>period</period>
>>> <quota>quota</quota>
>>> </vcpu>
>>> </cputune>
>>>
>>> Limit vcpus only, does not limit vm or hypervisor.
>>>
>>> 2.
>>> <cputune>
>>> <hypervisor>
>>> <period>period</period>
>>> <quota>quota</quota>
>>> </hypervisor>
>>> </cputune>
>>>
>>> Limit hypervisor only, does not limit vm or vcpus.
>>>
>>> 3.
>>> <cputune>
>>> <period>period</period>
>>> <quota>quota</quota>
>>> </cputune>
>>>
>>> Limit the whole vm, in this case vcpus and hypervisor are also limited.
>>>
>>> 4.
>>> <cputune>
>>> <period>period</period>
>>> <quota>quota</quota>
>>> <vcpu>
>>> <period>period</period>
>>> <quota>quota</quota>
>>> </vcpu>
>>> <hypervisor>
>>> <period>period</period>
>>> <quota>quota</quota>
>>> </hypervisor>
>>> </cputune>
>>
>> This is very complex, and the user should know how we implement it
>> and the period/quota's limit. If the user gives a wrong value, the
>> vm cannot start.
>>
>> We implement the limit like this:
>>
>> vm
>> |
>> ----------------------------
>> | ... | |
>> vcpu0 vcpun hypervisor
>>
>> If all is limited, the vm's quota should be greater than max(vcpu's quota, hypervisor's quota)
>> and vm's period should be less than min(vcpu's period, hypervisor's period).
>>
>> So I donot like this idea.
>>
>
>
> Hmm. my proposal is not so complicated as you say. And simpler than your way.
>
> <quota target='all|vcpu'> </quota> # all is default and limit the whole vm.
> # vcpu is just limit vcpus rather than whole vm.
> <period> .... </period> # period is shared in all settings.
>
> Isn't it ?
Do you mean this:
<cputune>
<vcpu>
<period>period</period>
<quota target='all|vcpu'>quota</quota>
</vcpu>
<hypervisor>
<period>period</period>
<quota>quota</quota>
</hypervisor>
</cputune>
Thanks
Wen Congyang
>
> Thanks,
> -Kame
>
>
>
--
libvir-list mailing list
libvir-list@xxxxxxxxxx
https://www.redhat.com/mailman/listinfo/libvir-list