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Date: Fri, 16 May 2008 06:51:01 +1000
From: Andrew Snow <andrew@modulus.org>
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Subject: Re: thread scheduling at mutex unlock
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> But I think that it is not "fair" that at re-lock former
> owner gets the lock immediately and the thread that waited on it for
> longer time doesn't get a chance.

I believe this is what yield() is for.  Before attempting a re-lock you 
should call yield() to allow other threads a chance to run.

(Side note: On FreeBSD, I believe only high priority threads will run 
when you yield().  As a workaround, I think you have to lower the 
thread's priority before yield() and then raise it again afterwards.)


- Andrew