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Cc: Perforce Change Reviews <perforce@freebsd.org>,
	Kip Macy <kmacy@freebsd.org>
Subject: Re: PERFORCE change 100089 for review
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On Mon, 26 Jun 2006, John Baldwin wrote:

> On Monday 26 June 2006 16:54, Kip Macy wrote:
>> http://perforce.freebsd.org/chv.cgi?CH=100089
>>
>> Change 100089 by kmacy@kmacy_storage:sun4v_work_sleepq on 2006/06/26
> 20:53:51
>>
>> 	add profiling for rwlocks
>> 	not convinced of correctness as there don't appear to be any contended
> rwlocks on my workloads
>
> Few things use them currently.  I have a patch to make the name cache use 
> them if you want it.

You may already have seen this, but I have a UNIX domain socket re-locking in 
//depot/user/rwatson/proto/src/sys/kern/uipc_usrreq.c that uses rwlocks and 
finer-grained mutexes, among other things.  Ideally this can generate some 
contention (although perhaps not too much).

Robert N M Watson
Computer Laboratory
University of Cambridge