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Subject: Re: [PATCH] trace: reorder struct ring_buffer_per_cpu to remove
 padding on 64bit
From: Richard Kennedy <richard@rsk.demon.co.uk>
To: rostedt@goodmis.org
Cc: Frederic Weisbecker <fweisbec@gmail.com>, Ingo Molnar <mingo@redhat.com>,
       lkml <linux-kernel@vger.kernel.org>,
       Arnaldo Carvalho de Melo <acme@infradead.org>
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Date: Thu, 25 Mar 2010 13:44:03 +0000
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On Thu, 2010-03-25 at 09:38 -0400, Steven Rostedt wrote:
> On Thu, 2010-03-25 at 11:27 +0000, Richard Kennedy wrote:
> > Reorder structure to remove 8 bytes of padding on 64 bit builds.
> > This shrinks the size to 128 bytes so allowing allocation from a smaller
> > slab & needed one fewer cache lines.
> > 
> 
> Thanks!
> 
> Just curious, did you use Arnaldo's pahole utility to find this?
> 
> -- Steve
No, but something similar I guess. I wrote my own tool that parses the
debug data & filters out the interesting results ;)

Richard