From mboxrd@z Thu Jan  1 00:00:00 1970
From: Matthias Schniedermeyer <ms@citd.de>
Subject: Re: [PATCH] sysctl: Add a feature to drop caches selectively
Date: Fri, 27 Jun 2014 10:41:39 +0200
Message-ID: <20140627084139.GA29704@citd.de>
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Cc: Artem Bityutskiy <dedekind1@gmail.com>,
	Bernd Schubert <bernd.schubert@itwm.fraunhofer.de>,
	Dave Chinner <david@fromorbit.com>,
	Thomas Knauth <thomas.knauth@gmx.de>,
	David Rientjes <rientjes@google.com>,
	Maksym Planeta <mcsim.planeta@gmail.com>,
	Alexander Viro <viro@zeniv.linux.org.uk>,
	linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org
To: =?iso-8859-1?B?THVr4T8=?= Czerner <lczerner@redhat.com>
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On 26.06.2014 13:57, Luk=E1? Czerner wrote:

> > So if the authors want to sell this new interface (in whatever form=
) to
> > the kernel community, they should start with providing a solid use-=
case,
> > with some more details, explore alternatives and show how the
> > alternatives do not work for them.
>=20
> Yes please, let's see some solid use-case for this.

Personally i would want it to verify files after copying them:
Especially while moving files:
- Copy a file
- <drop cache>
- Verify that it really is correct on stable storage
- Remove original file

Currently i choose either of the 3 ways:
- drop_caches
- umount/mount
- Write more data than memory in machine (Which is only an=20
approximnation and you have to verify in the same order the files were=20
written, so it is likely that any cache was thrashed in the meantime)

But having a way to selectivly "destory" the cache of a file would make=
=20
this task easier.




--=20

Matthias