Re: [ANNOUNCE] Linux 2.6 Real Time Kernel

From: Måns Rullgård
Date: Sat Oct 09 2004 - 14:42:04 EST


Lee Revell <rlrevell@xxxxxxxxxxx> writes:

>> > > To the best of my understanding, this still doesn't provide
>> > > deterministic hard-real-time performance in Linux.
>> >
>> > Using only the VP+IRQ thread patch, I ran my RT app for 11 million
>> > cycles yesterday, with a maximum delay of 190 usecs. How would this not
>> > satisfy a 200 usec hard RT constraint?
>>
>> I think the keyword here is "deterministic", isn't it?
>
> Well, depends what you mean by deterministic. Some RT apps only require
> an upper bound on response time. This is a form of determinism.

Sure, but running for a zillion cycles without breaking some limit
doesn't guarantee that it never will happen. Being able to give such
a guarantee is what determinism is about.

--
Måns Rullgård
mru@xxxxxxxxxx

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