From: Ted Ts'o <tytso@mit.edu>
Subject: Re: [RFC, PATCH] Avoid hot statistics cache line in ext4 extent
 cache
Date: Fri, 13 Apr 2012 15:33:56 -0400
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Cc: Linus Torvalds <torvalds@linux-foundation.org>,
	Andi Kleen <andi@firstfloor.org>,
	Vivek Haldar <haldar@google.com>,
	Andreas Dilger <adilger@dilger.ca>, linux-ext4@vger.kernel.org
To: Tim Chen <tim.c.chen@linux.intel.com>
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On Fri, Apr 13, 2012 at 12:26:53PM -0700, Tim Chen wrote:
> 
> The files are sparse files.  So the amount of IO is limited and we are
> not IO constrained.  
> 

... OK, and exactly how sparse are these files?  Can you say something
about the relatistic use case this workload is supposed to represent?
Or is this more of an artificial/micro benchmark?

					- Ted