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Date: Mon, 31 Mar 2003 16:02:12 -0800
From: Andrew Morton <akpm@digeo.com>
To: Ingo Oeser <ingo.oeser@informatik.tu-chemnitz.de>
Cc: piggin@cyberone.com.au, helgehaf@aitel.hist.no, erik@hensema.net,
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Subject: Re: Delaying writes to disk when there's no need
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Ingo Oeser <ingo.oeser@informatik.tu-chemnitz.de> wrote:
>
> On Mon, Mar 31, 2003 at 02:45:00PM -0800, Andrew Morton wrote:
> > It could have pretty bad failure modes.  Short-lived files in /tmp now
> > perform writeout, which needs to be waited on when those files are removed.
> 
> /tmp is not a problem, because this can be fixed by using tmpfs
> (I use 2GB of it with 1GB of RAM).

I don't.   These files get unlinked before they hit disk.

> The disk is idle, so this is not about performance, but power
> consumption. Spinning up a disk costs around 1-2 seconds, so you
> should come in with at least the amount of data you write in 1-2
> seconds for a spun down disk.

The requirements for portable computers are totally different.  You'd turn
the whole thing off for them.

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