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Date: Fri, 10 Jun 2011 16:59:54 +0100
From: Matthew Garrett <mjg59@srcf.ucam.org>
To: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Kyungmin Park <kmpark@infradead.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        Ankita Garg <ankita@in.ibm.com>, linux-arm-kernel@lists.infradead.org,
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        linux-pm@lists.linux-foundation.org, svaidy@linux.vnet.ibm.com,
        thomas.abraham@linaro.org
Subject: Re: [PATCH 00/10] mm: Linux VM Infrastructure to support Memory
 Power Management
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On Fri, Jun 10, 2011 at 08:11:21AM -0700, Paul E. McKenney wrote:

> Of course, on a server, you could get similar results by having a very
> large amount of memory (say 256GB) and a workload that needed all the
> memory only occasionally for short periods, but could get by with much
> less (say 8GB) the rest of the time.  I have no idea whether or not
> anyone actually has such a system.

For the server case, the low hanging fruit would seem to be 
finer-grained self-refresh. At best we seem to be able to do that on a 
per-CPU socket basis right now. The difference between active and 
self-refresh would seem to be much larger than the difference between 
self-refresh and powered down.

-- 
Matthew Garrett | mjg59@srcf.ucam.org
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