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From: Mark Lord <mlord@pobox.com>
To: Lukas Czerner <lczerner@redhat.com>
Cc: "Prof. Dr. Klaus Kusche" <klaus.kusche@computerix.info>,
	Ric Wheeler <ricwheeler@gmail.com>,
	dgilbert@interlog.com, linux-scsi@vger.kernel.org
Subject: Re: Good SAS adapters for 6 Gb/s SATA SSD's (with TRIM)?
Date: Fri, 12 Aug 2011 08:32:02 -0400	[thread overview]
Message-ID: <4E451D42.5050809@pobox.com> (raw)
In-Reply-To: <alpine.LFD.2.00.1108121143430.4535@dhcp-27-109.brq.redhat.com>

On 11-08-12 05:52 AM, Lukas Czerner wrote:
..
> wiper.sh is just a hack to do rally nasty thing to the filesystam
> (allocating all free space)

It actually does NOT allocate all of the free space,
but yes it does reserve *most* of it, leaving a few percent
or a few hundred MB free while it issues the DSM/TRIM commands.

And it uses the fallocate system call, so the reserved space
is not actually written to when reserved, nor when later freed.

I expect the next version of it to include support for FSTRIM,
but that is a much slower method, especially for offline TRIM.

Cheers
-- 
Mark Lord
Real-Time Remedies Inc.
mlord@pobox.com

  reply	other threads:[~2011-08-12 12:32 UTC|newest]

Thread overview: 17+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-08-11 15:18 Good SAS adapters for 6 Gb/s SATA SSD's (with TRIM)? Prof. Dr. Klaus Kusche
2011-08-11 19:59 ` Douglas Gilbert
2011-08-12  3:19   ` Douglas Gilbert
2011-08-12  7:16     ` Stefan /*St0fF*/ Hübner
2011-08-12 13:42       ` Douglas Gilbert
2011-08-14 19:59         ` Stefan Hübner
2011-08-12  8:04     ` Prof. Dr. Klaus Kusche
2011-08-12  8:15       ` Ric Wheeler
2011-08-12  8:48         ` Prof. Dr. Klaus Kusche
2011-08-12  9:01           ` Ric Wheeler
2011-08-12  9:24             ` Prof. Dr. Klaus Kusche
2011-08-12  9:35               ` Ric Wheeler
2011-08-12 11:14                 ` Lukas Czerner
2011-08-12  9:52               ` Lukas Czerner
2011-08-12 12:32                 ` Mark Lord [this message]
2011-08-12  9:17 ` Artem Bokhan
2011-08-12  9:34   ` Artem Bokhan

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