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Date: Thu, 26 May 2011 20:31:11 +0100
From: Matthew Garrett <mjg59@srcf.ucam.org>
To: "D. Jansen" <d.g.jansen@googlemail.com>
Cc: Oliver Neukum <oneukum@suse.de>, Dave Chinner <david@fromorbit.com>,
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Subject: Re: [rfc] Ignore Fsync Calls in Laptop_Mode
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On Thu, May 26, 2011 at 09:01:49AM +0200, D. Jansen wrote:

> Exactly. 0.5 Watts is a lot of energy on a modern system. And on some
> systems with proper link power management in sata and pcie it will be
> even higher (~1 Watt I think). Think not only of the work that will be
> lost if the system crashes (unlikely), but also of the work that could
> never be done because the battery was gone (a certainty).

I don't think link power management is relevant. The hysteresis there is 
sufficiently low that it's only going to make a difference during the 
point where you're actually throwing data across the link.

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