Re: How to setup low CPU priority domU

Jan Hejl
Sat, 05 Oct 2013 20:15:42 -0000

Hello,

sorry for late response. I''ve been on holidays.

Dne 26.9.2013 10:06, Dario Faggioli napsal(a):
> On mar, 2013-09-24 at 09:57 +0200, Jan Hejl wrote:
>> Hello everyone,
>>
> Hi,
>
>> i would like to use one of my domU with all 32 hardware cores but
>> with lower priority (something like nice 10), but setting cpu weight
>> seems to be someway unstable.
>>
> You mean you want that domU to have 32 vCPUs? Can I ask you from where
> this requirement comes from?
There''s a lot of free resource over night when everyone sleeps and i
want to use these resources to build video rendering farm. Does it makes
sense?
>
>> Dom0 is Gentoo with Xen 4.3.0, 2 AMD Opetrons 6274 (32 cores), 64GB of
>> memory, but dom0 runs on 16 cores and 32GB of memory. Hosts 5 linux
>> domUs with similiar configs, each from 2 to 4 cores, from 1GB to 4GB of
>> memory. DomU with all cores is Windows Server 2008R2 Enterprise with
>> Terminal Services installed.
>>
> Mmm... nice setup! :-P
Thank you. It''s just one of four slots in 2U
TWIN.
>
> Do you mind sending here the output of the following commands, to help
> us picture the situation better?
>
> ~# xl info -n
> ~# xl list -n
> ~# xl vcpu-list
>
> If possible, run the following two too:
>
> ~# xl debug-key u
> ~# xl dmesg > xl-dmesg.log
>
> And attach the xl-dmesg.log file.
Attached.
>
> Of course, do all the above with all your domains up and running, and
> after the re-weighting of the Win server.
>
>> When I set cpu-weight to 192 (others have 256 - default), it starts to
>> lag. Applications became pretty slow and unstable.
>>
> You mean apps inside the Win server with 32 vCPUs or in general?
Whole machine is slow. It behaves like old 386 PC when you disabled that
TURBO button. Everything slowed down.
>
> Regards,
> Dario
>
Thanks
Jan