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Subject: Re: Discard support (was Re: [PATCH] swap: send callback when swap
 slot is freed)
From: James Bottomley <James.Bottomley@suse.de>
To: Mark Lord <liml@rtr.ca>
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Date: Mon, 17 Aug 2009 15:28:12 -0500
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On Mon, 2009-08-17 at 16:19 -0400, Mark Lord wrote:
> James Bottomley wrote:
> > On Mon, 2009-08-17 at 14:21 -0400, Greg Freemyer wrote:
> >> On Mon, Aug 17, 2009 at 1:19 PM, James Bottomley<James.Bottomley@suse.de> wrote:
> >>> On Mon, 2009-08-17 at 13:08 -0400, Greg Freemyer wrote:
> ..
> >>>> Non-coalescing is believed detrimental,
> >>> It is?  Why?
> >> For the only compliant SSD in the wild, Mark has shown it to be true
> >> via testing.
> > 
> > He only said larger trims take longer.  As I said previously, if it's a
> > X+nY relationship, then we still benefit from accumulation up to some
> > value of n.
> ..
> 
> Err, what I said was, "rm -rf /usr/src/linux" takes over half an hour
> with uncoalesced TRIM, and only a scant few seconds in total *with*
> coalesced TRIM.

Yes, sorry, missed the Non- when I read that sentence.

James