From owner-freebsd-hackers@FreeBSD.ORG  Mon Mar 19 18:05:00 2007
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Date: Mon, 19 Mar 2007 14:04:58 -0400 (EDT)
From: Daniel Eischen <deischen@freebsd.org>
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To: Peter Holmes <peter_holmes2003@yahoo.com>
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Cc: fbsd hackers <freebsd-hackers@freebsd.org>
Subject: Re: Pthread spin locks
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On Mon, 19 Mar 2007, Peter Holmes wrote:

> I have a related question - it would be great if someone could help me. Let's 
> say there are multiple system scope pthreads running on an SMP system. Is 
> there a chance that if a pthread holding a spinlock is scheduled out (due to a 
> scheduling decision etc.) then other pthreads will be starved. Is there 
> anything the system provides to guard against pthread starvation.

No, especially if the threads hold other locks.
I have no idea why POSIX added spinlocks.  I don't
see why anyone would want to use them.

-- 
DE