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From: John Baldwin <jhb@freebsd.org>
To: Rick Macklem <rmacklem@uoguelph.ca>
Subject: Re: NFS server bottlenecks
Date: Mon, 15 Oct 2012 11:08:09 -0400
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Cc: Nikolay Denev <ndenev@gmail.com>, Garrett Wollman <wollman@freebsd.org>,
 FreeBSD Hackers <freebsd-hackers@freebsd.org>
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On Saturday, October 13, 2012 9:03:22 am Rick Macklem wrote:
> rick
> ps: I hope John doesn't mind being added to the cc list yet again. It's
>     just that I suspect he knows a fair bit about mutex implementation
>     and possible hardware cache line effects.

Currently mtx_pool just uses a simple array (I have patches to force the
array members to be cache-aligned, but they haven't been shown to help in
any benchmarks to date).  I do think though that I would prefer embedding
the mutexes in the hash table entries directly.  This is what we do for the
turnstile and sleep queue hash tables.

-- 
John Baldwin