Date: Fri, 14 Mar 2008 11:03:42 -0700 (PDT)
From: david@lang.hm
To: Theodore Tso <tytso@mit.edu>
cc: Ric Wheeler <ric@emc.com>, Benny Amorsen <benny+usenet@amorsen.dk>,
       linux-kernel@vger.kernel.org
Subject: Re: [ANNOUNCE] Ramback: faster than a speeding bullet
In-Reply-To: <20080314164952.GA7767@mit.edu>
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On Fri, 14 Mar 2008, Theodore Tso wrote:

> It depends on the workload, obviously.  I thought I remember someone
> on this thread talking about benchmark where they went from ~2000 to
> ~20 ops/sec once they added fsync().  I'm sure that was an extreme
> benchmarking workload that isn't at all representative of real-life
> usage, where you're usually do something else modifying the metadata
> of many tiny files over and over again.  :-)

I've seen this sort of thing with syslog, normal syslog at ~100 logs/sec, 
syslog without fsync >10,000 logs/sec.

if this is your situation then battery backed cache on your controller is 
the answer as it gives you almost full speed with the safety of fsync.

David Lang

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