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From: Alan Cox <alan@lxorguk.ukuu.org.uk>
To: "Theodore Ts'o" <tytso@mit.edu>
Cc: "Lasse Kärkkäinen" <ljkarkk2@cc.hut.fi>, linux-kernel@vger.kernel.org
Subject: Re: urandom is too slow
Date: Tue, 30 Oct 2012 21:38:50 +0000	[thread overview]
Message-ID: <20121030213850.7b987ddf@pyramind.ukuu.org.uk> (raw)
In-Reply-To: <20121030185403.GA5044@thunk.org>

> If you just want to wipe a disk, you shouldn't be using /dev/urandom for that
> purpose.

If you want to wipe a disk issue a security erase command via hdparm.
There is no guarantee that simply writing crap all over it will re-use
the same sectors of physical media, and for a flash drive it causes
massive wear and takes forever while a security erase is normally near
immediate.

Alan

  parent reply	other threads:[~2012-10-30 21:33 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-10-30 14:55 urandom is too slow Lasse Kärkkäinen
2012-10-30 18:54 ` Theodore Ts'o
2012-10-30 20:56   ` Pádraig Brady
2012-10-30 21:38   ` Alan Cox [this message]
2012-11-02  1:10     ` Lasse Kärkkäinen
2012-11-02 19:56       ` Theodore Ts'o

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