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Date: Sat, 29 Mar 2003 00:12:48 +0100
From: Pavel Machek <pavel@suse.cz>
To: Erik Hensema <erik@hensema.net>
Cc: linux-kernel@vger.kernel.org
Subject: Re: Delaying writes to disk when there's no need
Message-ID: <20030328231248.GH5147@zaurus.ucw.cz>
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Hi!

> In all kernels I've tested writes to disk are delayed a long time even when
> there's no need to do so.
> 
> A very simple test shows this: on an otherwise idle system, create a tar of
> a NFS-mounted filesystem to a local disk. The kernel starts writing out the
> data after 30 seconds, while a slow and steady stream would be much nicer
> to the system, I think.
> 

Well, doing writeback sooner when disks
are idle might be good idea; detecting
if disk is idle might not be too easy, through.

OTOH, raid resync already has some
such detection?
				Pavel
-- 
				Pavel
Written on sharp zaurus, because my Velo1 broke. If you have Velo you don't need...

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