[Engine-devel] CPU Pinning @engine

[Andrew Cathrow]

----- Original Message -----
> From: "Doron Fediuck" <dfediuck at redhat.com>
> To: dlaor at redhat.com
> Cc: engine-devel at ovirt.org
> Sent: Sunday, May 20, 2012 5:49:08 PM
> Subject: Re: [Engine-devel] CPU Pinning @engine
> 
> On 20/05/12 21:41, Dor Laor wrote:
> > On 05/17/2012 11:15 PM, Doron Fediuck wrote:
> >> On 17/05/12 20:28, Ayal Baron wrote:
> >>> "Live migration will not be supported for such VM's."
> >>>
> >>> Migration will work on homogeneous clusters so this should not be
> >>> enforced (not limited to VMs which are pinned to host) just give
> >>> a warning.
> >>>
> >> I agree, but if we wish to ping vCPUx to pCPUy in host a, we
> >> cannot ensure to have the same in host b,
> >> since it may have pCPUy too busy, so performance will degrade.
> >> Also, I hope you saw my general comment
> > 
> > Performance may degrade on any migration to loaded host regardless
> > of pinning.
> > 
> > There is not need to forbid migration. Instead, the SLA assurance
> > policy should verify the dedicated resources and match the target
> > w/ the guarantee and decide according to this.
> > 
> Thanks for the input.
> We may start with migration blocked in a configurable manner, so
> people who wish migrate to work
> will simply set the relevant configuration key.
> As for looking for a matched CPU, will add it as p2.

We shouldn't block migration
If a user wants to not migrate a cpu pinned VM then let them use the non-migratable flag in the UI.


> 
> >> about starting with a humble solution and gradually improving. In
> >> this context (auto)numa can help us,
> >> so we better do numa than handle migration for basic mode, risking
> >> performance issues.
> >>
> >>>
> >>> ----- Original Message -----
> >>>> From: "Doron Fediuck"<dfediuck at redhat.com>
> >>>> To: engine-devel at ovirt.org
> >>>> Sent: Thursday, May 17, 2012 2:42:46 PM
> >>>> Subject: [Engine-devel] CPU Pinning @engine
> >>>>
> >>>> Hi All,
> >>>> Currently the VDSM has a CPU pinning hook.
> >>>> We'd like to add better support of it into the engine itself.
> >>>> Here's a design draft to cover it:
> >>>> http://www.ovirt.org/wiki/Features/Design/cpu-pinning
> >>>>
> >>>> Please review and comment if needed.
> >>>>
> >>>> Thanks!
> >>>> --
> >>>>
> >>>> /d
> >>>>
> >>>> Never say "OOPS!" always say "Ah, Interesting!"
> >>>> _______________________________________________
> >>>> Engine-devel mailing list
> >>>> Engine-devel at ovirt.org
> >>>> http://lists.ovirt.org/mailman/listinfo/engine-devel
> >>>>
> >>> _______________________________________________
> >>> Engine-devel mailing list
> >>> Engine-devel at ovirt.org
> >>> http://lists.ovirt.org/mailman/listinfo/engine-devel
> >>
> >>
> > 
> 
> 
> --
> 
> /d
> 
> Never say "OOPS!" always say "Ah, Interesting!"
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