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Re: [Xen-devel] What about real time?

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Subject: Re: [Xen-devel] What about real time?
From: "Mark A. Williamson" <mark.williamson@xxxxxxxxxxxx>
Date: Tue, 9 Nov 2004 13:51:42 +0000
Cc: Andrew W.Donoho <awd@xxxxxxx>
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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!


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.)
> Andrew
> ____________________________________
> Andrew W. Donoho
> awd@xxxxxxx, PGP Key ID: 0x81D0F250
> +1 (512) 453-6652 (o), +1 (512) 750-7596 (m)

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