WARNING - OLD ARCHIVES

This is an archived copy of the Xen.org mailing list, which we have preserved to ensure that existing links to archives are not broken. The live archive, which contains the latest emails, can be found at http://lists.xen.org/
   
 
 
Xen 
 
Home Products Support Community News
 
   
 

xen-devel

Re: [Xen-devel] planned csched improvements?

To: Jan Beulich <JBeulich@xxxxxxxxxx>, Kevin Tian <kevin.tian@xxxxxxxxx>
Subject: Re: [Xen-devel] planned csched improvements?
From: Keir Fraser <keir.fraser@xxxxxxxxxxxxx>
Date: Mon, 12 Oct 2009 08:34:14 +0100
Cc: "xen-devel@xxxxxxxxxxxxxxxxxxx" <xen-devel@xxxxxxxxxxxxxxxxxxx>
Delivery-date: Mon, 12 Oct 2009 00:35:11 -0700
Envelope-to: www-data@xxxxxxxxxxxxxxxxxxx
In-reply-to: <4AD2F68F020000780001934B@xxxxxxxxxxxxxxxxxx>
List-help: <mailto:xen-devel-request@lists.xensource.com?subject=help>
List-id: Xen developer discussion <xen-devel.lists.xensource.com>
List-post: <mailto:xen-devel@lists.xensource.com>
List-subscribe: <http://lists.xensource.com/mailman/listinfo/xen-devel>, <mailto:xen-devel-request@lists.xensource.com?subject=subscribe>
List-unsubscribe: <http://lists.xensource.com/mailman/listinfo/xen-devel>, <mailto:xen-devel-request@lists.xensource.com?subject=unsubscribe>
Sender: xen-devel-bounces@xxxxxxxxxxxxxxxxxxx
Thread-index: AcpLDY3LmDZw/biITUWQ42DjjSy2iAAANfRn
Thread-topic: [Xen-devel] planned csched improvements?
User-agent: Microsoft-Entourage/12.20.0.090605
On 12/10/2009 08:27, "Jan Beulich" <JBeulich@xxxxxxxxxx> wrote:

>> there's a migration delay (default is 1ms) to judge cache hotness and
>> thus avoid unnecessary migration. However so far it's only checked
>> when one cpu wants to steal vcpus from other runqueue. Possibly it
>> makes sense to add this check to csched_vcpu_acct, as a cold cache
>> and cascade of other VCPU migrations could easily beat benefit on a
>> "more idle" socket.
> 
> Where do you see this 1ms delay - I can't seem to spot it...

The option of interest is vcpu_migration_delay, but it defaults to zero
(disabled). Intel explicitly set it to 1000 (1ms) for their tests.

 -- Keir



_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel

<Prev in Thread] Current Thread [Next in Thread>