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From: NeilBrown <neilb@suse.de>
To: Chris Friesen <chris.friesen@genband.com>
Cc: linux-raid@vger.kernel.org
Subject: Re: RFC: use TRIM data from filesystems to speed up array rebuild?
Date: Wed, 5 Sep 2012 06:21:13 +1000	[thread overview]
Message-ID: <20120905062113.05e4f0f4@notabene.brown> (raw)
In-Reply-To: <50464322.3010509@genband.com>

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On Tue, 04 Sep 2012 12:06:26 -0600 Chris Friesen <chris.friesen@genband.com>
wrote:

> 
> Hi,
> 
> I'm not really a filesystem guy so this may be a really dumb question.
> 
> We currently have an issue where we have a ~1TB RAID1 array that is 
> mostly given over to LVM.  If we swap one of the disks it will rebuild 
> everything, even though we may only be using a small fraction of the space.
> 
> This got me thinking.  Has anyone given thought to using the TRIM 
> information from filesystems to allow the RAID code to maintain a 
> bitmask of used disk blocks and only sync the ones that are actually used?
> 
> Presumably this bitmask would itself need to be stored on the disk.
> 
> Thanks,
> Chris
> 
> 

Something like this?
  http://neil.brown.name/blog/20110216044002#5

NeilBrown

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  parent reply	other threads:[~2012-09-04 20:21 UTC|newest]

Thread overview: 9+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-09-04 18:06 RFC: use TRIM data from filesystems to speed up array rebuild? Chris Friesen
2012-09-04 19:11 ` Ric Wheeler
2012-09-04 20:24   ` NeilBrown
2012-09-04 22:59     ` Ric Wheeler
2012-09-06 17:17     ` Benjamin ESTRABAUD
2012-09-06 18:42       ` David Brown
2012-09-07  9:23         ` Benjamin ESTRABAUD
2012-09-04 20:21 ` NeilBrown [this message]
2012-09-04 20:28   ` Chris Friesen

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