From mboxrd@z Thu Jan  1 00:00:00 1970
From: Keir Fraser <keir.fraser@eu.citrix.com>
Subject: Re: [PATCH] only set scheduler timer for non-idle CPU
Date: Thu, 02 Apr 2009 14:18:41 +0100
Message-ID: <C5FA79C1.5885%keir.fraser@eu.citrix.com>
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To: Keir Fraser <keir.fraser@eu.citrix.com>, Thomas Pfeuffer <thomas.pfeuffer@mytum.de>, "Yu, Ke" <ke.yu@intel.com>, "xen-devel@lists.xensource.com" <xen-devel@lists.xensource.com>
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On 02/04/2009 14:06, "Keir Fraser" <keir.fraser@eu.citrix.com> wrote:

>> I think your patch is not good in case sedf-scheduler is used. If idle V=
CPU
>> is the current "running" VCPU, the scheduler timer is set to the next "p=
eriod
>> begin" of the first VCPU in the wait queue.
>> Your patch prevents sedf from taking the VCPUs waiting for their next pe=
riod
>> into the runnable queue again.
>=20
> It=B9s probably cleaner always to respect the specific scheduler=B9s scheduli=
ng
> quantum in schedule.c, but then have sched_credit.c return a very large
> quantum (large as possible) for the idle VCPU.

I checked in something to this effect as c/s 19500.

 -- Keir