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From: Ben Kelly <ben@wanderview.com>
To: John Baldwin <jhb@freebsd.org>
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Date: Mon, 18 May 2009 22:16:46 -0400
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Cc: Adam McDougall <mcdouga9@egr.msu.edu>, freebsd-current@freebsd.org,
	Artem Belevich <fbsdlist@src.cx>
Subject: Re: [patch] zfs livelock and thread priorities
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On May 18, 2009, at 11:29 AM, John Baldwin wrote:
> On Saturday 16 May 2009 12:40:44 pm Ben Kelly wrote:
>>   1) It changes the kproc(9) API by adding a kproc_create_priority()
>> function that allows you to set the priority of the newly created
>> thread.  I'm not sure how people feel about this.
>
> Actually, I almost think we should just add a priority argument to  
> each of the
> routines that creates a new kthread/kproc.  Perhaps allow a priority  
> of 0 to
> let the thread run with the default priority.  Hmm, it looks like  
> kthreads
> default to running with whatever thread0 runs at (PVM) which is  
> probably not
> really ideal.  Having an explicit priority for every kthread would  
> probably
> be best.  Most kthreads should probably be at PZERO by default I  
> think.

If this approach was taken would it make sense to use a flag to  
indicate "use the specified priority" since 0 is a valid priority value?

Thanks.

- Ben