From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jeff Layton <laytonjb@att.net>
Subject: Re: TRIM support in drivers and dm/md?
Date: Thu, 04 Nov 2010 10:46:45 -0400
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References: <4CD2B2EF.4050005@att.net> <20101104134014.GB21931@parisc-linux.org>
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To: Matthew Wilcox <matthew@wil.cx>
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  On 11/04/2010 09:40 AM, Matthew Wilcox wrote:
> On Thu, Nov 04, 2010 at 09:19:43AM -0400, Jeff Layton wrote:
>> Do many of the SATA controllers support TRIM? (i.e. pass
>> the TRIM command to the SSD). Does anyone know
>> anything about dm/md supporting TRIM? (I'm thinking LVM
>> and software RAID tools).
> As far as I know, there's nothing to be done in any SATA controller
> driver to support TRIM.  It's just up to the drive whether it understands
> the command.
That's the rub. I've heard that many drivers don't understand
the command. So I'm curious what drivers do and any experience
anyone might have.

Thanks!