From: Keir Fraser <keir.fraser@eu.citrix.com>
To: Jeremy Fitzhardinge <jeremy@goop.org>,
Mukesh Rathor <mukesh.rathor@oracle.com>
Cc: "Xen-devel@lists.xensource.com" <Xen-devel@lists.xensource.com>
Subject: Re: Linux spin lock enhancement on xen
Date: Wed, 18 Aug 2010 18:09:22 +0100 [thread overview]
Message-ID: <C891D252.1E4BD%keir.fraser@eu.citrix.com> (raw)
In-Reply-To: <4C6C0C3D.2070508@goop.org>
On 18/08/2010 17:37, "Jeremy Fitzhardinge" <jeremy@goop.org> wrote:
> I don't see why the guest should micromanage Xen's scheduler decisions.
> If a VCPU is waiting for another VCPU and can put itself to sleep in the
> meantime, then its up to Xen to take advantage of that newly freed PCPU
> to schedule something. It may decide to run something in your domain
> that's runnable, or it may decide to run something else. There's no
> reason why the spinlock holder is the best VCPU to run overall, or even
> the best VCPU in your domain.
>
> My view is you should just put any VCPU which has nothing to do to
> sleep, and let Xen sort out the scheduling of the remainder.
Yeah, I'm no fan of yield or yield-to type operations. I'd reserve the right
to implement both of them as no-op.
-- Keir
next prev parent reply other threads:[~2010-08-18 17:09 UTC|newest]
Thread overview: 23+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-08-17 1:33 Linux spin lock enhancement on xen Mukesh Rathor
2010-08-17 7:33 ` Keir Fraser
2010-08-17 7:53 ` Jan Beulich
2010-08-18 1:58 ` Mukesh Rathor
2010-08-17 14:34 ` Ky Srinivasan
2010-08-18 1:58 ` Mukesh Rathor
2010-08-17 17:43 ` Jeremy Fitzhardinge
2010-08-18 1:58 ` Mukesh Rathor
2010-08-18 16:37 ` Jeremy Fitzhardinge
2010-08-18 17:09 ` Keir Fraser [this message]
2010-08-19 2:52 ` Mukesh Rathor
2010-08-24 8:08 ` George Dunlap
2010-08-24 8:20 ` Keir Fraser
2010-08-24 8:43 ` George Dunlap
2010-08-24 8:48 ` Jan Beulich
2010-08-24 9:09 ` George Dunlap
2010-08-24 13:25 ` Jan Beulich
2010-08-24 16:11 ` George Dunlap
2010-08-26 14:08 ` Tim Deegan
2010-08-25 1:03 ` Dong, Eddie
2010-08-26 2:13 ` Mukesh Rathor
2010-08-19 2:52 ` Mukesh Rathor
2010-08-23 21:33 ` Jeremy Fitzhardinge
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