Re: [Xen-devel] What about real time? - Mark A. Williamson - com.xensource.lists.xen-devel

3 messages in com.xensource.lists.xen-develRe: [Xen-devel] What about real time?

From	Sent On	Attachments
Andrew W.Donoho	08 Nov 2004 15:50
Keir Fraser	08 Nov 2004 23:22
Mark A. Williamson	09 Nov 2004 05:51

Subject:	Re: [Xen-devel] What about real time?
From:	Mark A. Williamson (mark...@cl.cam.ac.uk)
Date:	11/09/2004 05:51:20 AM
List:	com.xensource.lists.xen-devel

There's a soft realtime scheduler in Xen called Atropos, which can give CPU share and latency guarantees to domains. This is not the default scheduler and it's got some annoying bug in that's throwing everything off, so it's not worth enabling for now. Fixing it is on my list of things to do on a slow weekend ;-)

As Keir says, once you start using services from other domains, things get rather more complicated regarding latency!

Mark

On Monday 08 Nov 2004 23:50, Andrew W.Donoho wrote:

Folks,

I know that Xen is designed for servers and such. But defined latency (e.g. real time) responsiveness is one of those characteristics that needs to be addressed early in the development lifecycle. What are the team's thoughts on achieving some sort of latency guarantee. (No fair punting by saying that some I/O devices can never guarantee latency, those devices do not need to be supported for defined latency situations.)

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