Re: web page on O(1) scheduler

Mike Galbraith (efault@gmx.de)
Thu, 22 May 2003 11:52:24 +0200


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At 10:56 AM 5/21/2003 -0700, David Mosberger wrote:
> >>>>> On Wed, 21 May 2003 11:26:31 +0200, Mike Galbraith <efault@gmx.de>
> said:
>
> Mike> The page mentions persistent starvation. My own explorations
> Mike> of this issue indicate that the primary source is always
> Mike> selecting the highest priority queue.
>
>My working assumption is that the problem is a bug with the dynamic
>prioritization. The task receiving the signals calls sleep() after
>handling a signal and hence it's dynamic priority should end up higher
>than the priority of the task sending signals (since the sender never
>relinquishes the CPU voluntarily).
>
>However, I haven't actually had time to look at the relevant code, so
>I may be missing something. If you understand the issue better,
>please explain to me why this isn't a dynamic priority issue.

You're right, it looks like a corner case. It works fine here with the
attached diff.

-Mike
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