From: Theodore Tso <tytso@mit.edu>
To: Thomas Glanzmann <thomas@glanzmann.de>,
Arjan van de Ven <arjan@infradead.org>,
tytso@thunk.org, LKML <linux-kernel@vger.kernel.org>,
linux-ext4@vger.kernel.org
Subject: Re: zero out blocks of freed user data for operation a virtual machine environment
Date: Mon, 25 May 2009 08:03:20 -0400 [thread overview]
Message-ID: <20090525120320.GA25908@mit.edu> (raw)
In-Reply-To: <20090524173933.GD24753@cip.informatik.uni-erlangen.de>
On Sun, May 24, 2009 at 07:39:33PM +0200, Thomas Glanzmann wrote:
> Hello,
>
> > > tunable feature that zeroes our free data
>
> > wouldn't it be better if the VM's would just support the TRIM command?
>
> the resources available to me indicate that the TRIM command is a not
> yet standarized command targeted at SSD disks to indicate free disk
> space. Does ext3/4 trigger a block device layer call that could result
> in a TRIM command?
Yes, it does, sb_issue_discard(). So if you wanted to hook into this
routine with a function which issued calls to zero out blocks, it
would be easy to create a private patch.
- Ted
next prev parent reply other threads:[~2009-05-25 12:03 UTC|newest]
Thread overview: 18+ messages / expand[flat|nested] mbox.gz Atom feed top
2009-05-24 17:00 zero out blocks of freed user data for operation a virtual machine environment Thomas Glanzmann
2009-05-24 17:15 ` Arjan van de Ven
2009-05-24 17:39 ` Thomas Glanzmann
2009-05-25 12:03 ` Theodore Tso [this message]
2009-05-25 12:34 ` Thomas Glanzmann
2009-05-25 13:14 ` Goswin von Brederlow
2009-05-25 14:01 ` Thomas Glanzmann
[not found] ` <f3177b9e0905251023n762b815akace1ae34e643458e@mail.gmail.com>
2009-05-25 17:26 ` Chris Worley
2009-05-26 10:22 ` Goswin von Brederlow
2009-05-26 16:52 ` Chris Worley
2009-05-28 19:27 ` Goswin von Brederlow
2009-05-25 3:29 ` David Newall
2009-05-25 5:26 ` Thomas Glanzmann
2009-05-25 7:48 ` Ron Yorston
2009-05-25 10:50 ` Thomas Glanzmann
2009-05-25 12:06 ` Theodore Tso
2009-05-25 21:19 ` Bill Davidsen
2009-05-26 4:45 ` Thomas Glanzmann
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