linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: James Bottomley <James.Bottomley@HansenPartnership.com>
To: Jeff Garzik <jeff@garzik.org>
Cc: Matthew Wilcox <matthew@wil.cx>,
	Jens Axboe <jens.axboe@oracle.com>,
	Boaz Harrosh <bharrosh@panasas.com>,
	Hugh Dickins <hugh@veritas.com>,
	Matthew Wilcox <willy@linux.intel.com>,
	linux-ide@vger.kernel.org, linux-kernel@vger.kernel.org,
	linux-scsi@vger.kernel.org,
	Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>,
	Mark Lord <lkml@rtr.ca>
Subject: Re: New TRIM/UNMAP tree published (2009-05-02)
Date: Sun, 03 May 2009 14:37:56 -0500	[thread overview]
Message-ID: <1241379476.5596.92.camel@mulgrave.int.hansenpartnership.com> (raw)
In-Reply-To: <49FDEE64.5090302@garzik.org>

On Sun, 2009-05-03 at 15:20 -0400, Jeff Garzik wrote:
> Is WRITE SAME associated with this current DISCARD work, or is that just 
> a similar example?  I'm unfamiliar with its issues...

It's an adjunct body of work.  T10 apparently ratified both UNMAP and
the WRITE SAME extensions.  What WRITE SAME does is write the same data
block to multiple contiguous locations as specified in the CDB.  What
the thin provisioning update did for it is allow you to specify a flag
saying I want these sectors unmapped.   The perceived benefit of WRITE
SAME is that you specify (with the write same data ... presumably all
zeros) what an unmapped sector will return if it's ever read from again,
which was a big argument in the UNMAP case.

James



  reply	other threads:[~2009-05-03 19:38 UTC|newest]

Thread overview: 59+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2009-04-02 14:37 [PATCH 1/5] Block: Discard may need to allocate pages Matthew Wilcox
2009-04-02 14:37 ` [PATCH 2/5] Make DISCARD_BARRIER and DISCARD_NOBARRIER writes instead of reads Matthew Wilcox
2009-04-02 14:37   ` [PATCH 3/5] ata: Add TRIM infrastructure Matthew Wilcox
2009-04-02 14:37     ` [PATCH 4/5] ide: Add support for TRIM Matthew Wilcox
2009-04-02 14:37       ` [PATCH 5/5] libata: " Matthew Wilcox
2009-04-02 17:20         ` Mark Lord
2009-04-02 17:55           ` Matthew Wilcox
2009-04-16 20:25         ` Mark Lord
2009-04-17 19:44           ` Mark Lord
2009-04-02 15:58       ` [PATCH 4/5] ide: " Sergei Shtylyov
2009-04-02 16:28         ` Matthew Wilcox
2009-04-02 16:38           ` Sergei Shtylyov
2009-04-02 16:51             ` Matthew Wilcox
2009-04-02 19:37               ` Bartlomiej Zolnierkiewicz
2009-04-07 21:38                 ` Bartlomiej Zolnierkiewicz
2009-04-07 22:15                   ` Matthew Wilcox
2009-04-07 22:26                     ` Jeff Garzik
2009-04-07 22:35                     ` Bartlomiej Zolnierkiewicz
2009-04-07 17:20       ` Jeff Garzik
2009-04-07 17:57         ` Mark Lord
2009-04-07 18:10           ` Markus Trippelsdorf
2009-04-07 19:58             ` Mark Lord
2009-04-08  7:14               ` Markus Trippelsdorf
2009-04-08 14:25                 ` Mark Lord
2009-04-08 14:33       ` Mark Lord
2009-04-08 14:44         ` Dongjun Shin
2009-04-08 14:59         ` Jeff Garzik
2009-04-08 15:50           ` Mark Lord
2009-04-02 15:55     ` [PATCH 3/5] ata: Add TRIM infrastructure Sergei Shtylyov
2009-04-02 16:18       ` Matthew Wilcox
2009-04-02 16:32         ` Sergei Shtylyov
2009-04-02 16:47           ` Matthew Wilcox
2009-04-07  0:02     ` Jeff Garzik
2009-04-05 12:28 ` [PATCH 1/5] Block: Discard may need to allocate pages Boaz Harrosh
2009-04-06 20:34   ` Matthew Wilcox
2009-05-03  6:11   ` Matthew Wilcox
2009-05-03  7:16     ` New TRIM/UNMAP tree published (2009-05-02) Matthew Wilcox
2009-05-03 13:07       ` Hugh Dickins
2009-05-03 14:48         ` Matthew Wilcox
2009-05-03 15:02           ` Boaz Harrosh
2009-05-03 15:42             ` Matthew Wilcox
2009-05-03 16:34               ` Boaz Harrosh
2009-05-03 18:34                 ` Jeff Garzik
2009-05-03 18:40                   ` Jeff Garzik
2009-05-03 19:04                     ` James Bottomley
2009-05-03 19:20                       ` Jeff Garzik
2009-05-03 19:37                         ` James Bottomley [this message]
2009-05-04 14:03                           ` Douglas Gilbert
2009-05-04 14:40                             ` James Bottomley
2009-05-04 15:11                               ` Douglas Gilbert
2009-05-04 15:23                                 ` James Bottomley
2009-05-03 19:47                         ` James Bottomley
2009-05-03 22:47                           ` Jeff Garzik
2009-05-04 15:28                             ` Boaz Harrosh
2009-05-03 21:48                   ` Matthew Wilcox
2009-05-03 22:54                     ` Jeff Garzik
2009-05-03 18:48               ` Bartlomiej Zolnierkiewicz
2009-05-03 15:05           ` Hugh Dickins
2009-04-17 21:23 ` [PATCH 1/5] Block: Discard may need to allocate pages Mark Lord

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=1241379476.5596.92.camel@mulgrave.int.hansenpartnership.com \
    --to=james.bottomley@hansenpartnership.com \
    --cc=bharrosh@panasas.com \
    --cc=bzolnier@gmail.com \
    --cc=hugh@veritas.com \
    --cc=jeff@garzik.org \
    --cc=jens.axboe@oracle.com \
    --cc=linux-ide@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-scsi@vger.kernel.org \
    --cc=lkml@rtr.ca \
    --cc=matthew@wil.cx \
    --cc=willy@linux.intel.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).