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Date: Tue, 31 Jan 2006 20:28:43 -0500 (EST)
From: Daniel Eischen <deischen@freebsd.org>
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To: kurt@intricatesoftware.com
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Cc: freebsd-threads@freebsd.org
Subject: Re: kse: high prio threads starving low prio threads
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On Tue, 31 Jan 2006, Kurt Miller wrote:

> I'm working on 1.5 jdk certification on 5.4 and 6.0. One of the
> jck tests hangs because a high priority thread that is yielding
> is starving the lower priority threads. The following program
> demonstrates this problem. Using libthr the program finishes.
> Using kse hangs using all three scheduling policies.
>
> Is this the expected behavior of kse?

It is the expected behavior for any POSIX threads library
that supports SCHED_FIFO and priorities and also running
on a system with one scheduling allocation domain (one CPU).
libthr does not support posix priority scheduling.

>
> Is there a work-around to the starving issue?

It is working as it should.  Recode it not to use priorities
if that is what you want.

-- 
DE