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

[Keir F. <Kei...@cl...>]

Depends what Xen services you want to use. :-)

If you run a RTOS with its own device drivers on its own CPU (not
sharing with anyone else) then you will probably find that Xen adds
very little jitter already.

If you want to be able to use services in other guests (e.g., remote
device drivers) that are multiplexed, then the problem is (at least)
much much harder.

 -- Keir

> 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@DDG.com, PGP Key ID: 0x81D0F250
> +1 (512) 453-6652 (o), +1 (512) 750-7596 (m)
> 
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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@DDG.com, PGP Key ID: 0x81D0F250
+1 (512) 453-6652 (o), +1 (512) 750-7596 (m)


--Apple-Mail-23--755923030
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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


<fontfamily><param>Helvetica</param>____________________________________

Andrew W. Donoho

awd@DDG.com, PGP Key ID: 0x81D0F250

+1 (512) 453-6652 (o), +1 (512) 750-7596 (m)


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