Date: Sun, 5 Mar 2006 11:22:48 -0800
From: Mark Fasheh <mark.fasheh@oracle.com>
To: Andrew Morton <akpm@osdl.org>
Cc: Daniel Phillips <phillips@google.com>, linux-kernel@vger.kernel.org,
       ocfs2-devel@oss.oracle.com
Subject: Re: Ocfs2 performance bugs of doom
Message-ID: <20060305192247.GH31587@ca-server1.us.oracle.com>
Reply-To: Mark Fasheh <mark.fasheh@oracle.com>
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On Fri, Mar 03, 2006 at 11:36:17PM -0800, Andrew Morton wrote:
> >  -	hash = full_name_hash(name, len);
> 
> err, you might want to calculate that hash outside the spinlock.
Hmm, good catch.

> Maybe have a lock per bucket, too.
That could be an avenue to explore. I guess we probably want to optimize the
actual lookup and memory usage before looking at that.

> A 1MB hashtable is verging on comical.  How may data are there in total?
Yes 1MB is much too big. We're looking right now at 3 lock resources per
inode, so total number of elements depends upon your file system I suppose.
Hopefully I'll have some time today to run some basic tests which may show
us what size strikes a better balance of performance versus memory overhead.
	--Mark

--
Mark Fasheh
Senior Software Developer, Oracle
mark.fasheh@oracle.com
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