From: Valdis.Kletnieks@vt.edu
To: Tejun Heo <htejun@gmail.com>
Cc: david@lang.hm, Stefan Bader <Stefan.Bader@de.ibm.com>,
Phillip Susi <psusi@cfl.rr.com>,
device-mapper development <dm-devel@redhat.com>,
linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org,
linux-raid@vger.kernel.org, Jens Axboe <jens.axboe@oracle.com>,
David Chinner <dgc@sgi.com>,
Andreas Dilger <adilger@clusterfs.com>,
ric@emc.com
Subject: Re: [dm-devel] Re: [RFD] BIO_RW_BARRIER - what it means for devices, filesystems, and dm/md.
Date: Fri, 01 Jun 2007 13:07:07 -0400 [thread overview]
Message-ID: <10553.1180717627@turing-police.cc.vt.edu> (raw)
In-Reply-To: Your message of "Fri, 01 Jun 2007 16:16:01 +0900." <465FC7B1.3060309@gmail.com>
[-- Attachment #1: Type: text/plain, Size: 930 bytes --]
On Fri, 01 Jun 2007 16:16:01 +0900, Tejun Heo said:
> Don't those thingies usually have NV cache or backed by battery such
> that ORDERED_DRAIN is enough?
Probably *most* do, but do you really want to bet the user's data on it?
> The problem is that the interface between the host and a storage device
> (ATA or SCSI) is not built to communicate that kind of information
> (grouped flush, relaxed ordering...). I think battery backed
> ORDERED_DRAIN combined with fine-grained host queue flush would be
> pretty good. It doesn't require some fancy new interface which isn't
> gonna be used widely anyway and can achieve most of performance gain if
> the storage plays it smart.
Yes, that would probably be "pretty good". But how do you get the storage
device to *reliably* tell the truth about what it actually implements? (Consider
the number of devices that downright lie about their implementation of cache
flushing....)
[-- Attachment #2: Type: application/pgp-signature, Size: 226 bytes --]
next prev parent reply other threads:[~2007-06-01 17:08 UTC|newest]
Thread overview: 102+ messages / expand[flat|nested] mbox.gz Atom feed top
2007-05-25 7:58 Neil Brown
2007-05-25 11:15 ` David Chinner
2007-05-25 11:49 ` Jens Axboe
2007-05-25 14:49 ` [dm-devel] " Phillip Susi
2007-05-28 18:32 ` Jens Axboe
2007-05-25 13:52 ` Stefan Bader
2007-05-28 1:37 ` Neil Brown
2007-05-29 9:12 ` Stefan Bader
2007-05-25 15:11 ` [dm-devel] " Phillip Susi
2007-05-26 1:03 ` Andreas Dilger
2007-05-26 10:27 ` Tejun Heo
2007-05-28 1:30 ` Neil Brown
2007-05-28 2:45 ` David Chinner
2007-05-28 2:57 ` Neil Brown
2007-05-28 4:29 ` David Chinner
2007-05-31 0:46 ` Neil Brown
2007-05-31 0:57 ` [dm-devel] " Alasdair G Kergon
2007-05-31 1:07 ` Alasdair G Kergon
2007-05-31 1:11 ` David Chinner
2007-05-28 4:48 ` Timothy Shimmin
2007-05-29 6:45 ` Jeremy Higdon
2007-05-29 20:03 ` Phillip Susi
2007-05-29 23:48 ` David Chinner
2007-05-30 0:01 ` david
2007-05-30 6:17 ` David Chinner
2007-05-30 8:55 ` Stefan Bader
2007-05-30 16:52 ` david
2007-05-31 0:20 ` David Chinner
2007-05-31 6:26 ` Jens Axboe
2007-05-31 7:03 ` David Chinner
2007-05-31 7:06 ` Jens Axboe
2007-05-31 13:30 ` Bill Davidsen
2007-05-31 13:36 ` Jens Axboe
2007-06-01 16:04 ` Bill Davidsen
2007-06-02 14:51 ` Jens Axboe
2007-06-02 19:55 ` Bill Davidsen
2007-06-01 3:16 ` Tejun Heo
2007-06-01 8:21 ` Jens Axboe
2007-06-02 9:20 ` Tejun Heo
2007-06-02 14:34 ` Jens Axboe
2007-06-02 22:57 ` Guy Watkins
2007-06-04 7:39 ` Tejun Heo
2007-05-31 18:31 ` Phillip Susi
2007-05-31 19:00 ` Jens Axboe
2007-05-31 19:21 ` david
2007-05-31 19:40 ` Jens Axboe
2007-05-31 23:34 ` David Chinner
2007-06-01 5:59 ` Neil Brown
2007-06-01 6:11 ` Jens Axboe
2007-06-01 7:53 ` David Chinner
2007-06-01 23:56 ` Bill Davidsen
2007-05-31 18:24 ` Phillip Susi
2007-05-30 16:45 ` Phillip Susi
2007-05-30 20:27 ` [dm-devel] " Phillip Susi
2007-05-31 6:24 ` Jens Axboe
2007-05-31 18:37 ` Phillip Susi
2007-05-31 18:58 ` Jens Axboe
2007-06-02 0:04 ` Bill Davidsen
2007-05-28 9:29 ` Tejun Heo
2007-05-28 9:43 ` [dm-devel] " Alasdair G Kergon
2007-05-29 9:25 ` Stefan Bader
2007-05-29 22:05 ` Alasdair G Kergon
2007-05-30 9:12 ` Stefan Bader
2007-05-30 10:41 ` Alasdair G Kergon
2007-05-30 16:55 ` Phillip Susi
2007-05-31 11:14 ` Stefan Bader
2007-06-01 3:25 ` Tejun Heo
2007-06-01 5:55 ` david
2007-06-01 7:16 ` Tejun Heo
2007-06-01 17:07 ` Valdis.Kletnieks [this message]
2007-06-01 18:09 ` Tejun Heo
2007-07-10 18:39 ` Ric Wheeler
2007-07-10 23:40 ` Valdis.Kletnieks
2007-07-11 2:49 ` Tejun Heo
2007-07-11 22:44 ` Ric Wheeler
2007-07-12 17:34 ` Valdis.Kletnieks
2007-07-12 19:43 ` Ric Wheeler
2007-07-12 23:10 ` Guy Watkins
2007-07-13 11:30 ` Ric Wheeler
2007-07-11 2:51 ` Tejun Heo
2007-05-29 19:59 ` Phillip Susi
2007-05-31 0:22 ` Neil Brown
2007-05-30 9:35 ` Jens Axboe
2007-07-05 12:28 ` Tejun Heo
2007-07-09 12:27 ` Jens Axboe
2007-07-18 10:56 ` [PATCH] block: cosmetic changes Tejun Heo
2007-07-18 10:59 ` [PATCH] block: factor out bio_check_eod() Tejun Heo
2007-07-18 11:06 ` Jens Axboe
2007-07-18 11:18 ` Tejun Heo
2007-07-18 11:31 ` Jens Axboe
2007-07-18 11:33 ` Tejun Heo
2007-07-18 11:34 ` Jens Axboe
2007-07-18 11:41 ` Tejun Heo
2007-07-18 11:45 ` Jens Axboe
2007-07-18 11:49 ` Jens Axboe
2007-07-18 12:34 ` Tejun Heo
2007-07-18 12:31 ` Jens Axboe
2007-05-28 11:17 ` [RFD] BIO_RW_BARRIER - what it means for devices, filesystems, and dm/md Nikita Danilov
2007-05-31 3:31 ` Neil Brown
2007-05-28 14:43 ` Bill Davidsen
2007-05-31 0:37 ` Neil Brown
2007-05-31 12:28 ` Bill Davidsen
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=10553.1180717627@turing-police.cc.vt.edu \
--to=valdis.kletnieks@vt.edu \
--cc=Stefan.Bader@de.ibm.com \
--cc=adilger@clusterfs.com \
--cc=david@lang.hm \
--cc=dgc@sgi.com \
--cc=dm-devel@redhat.com \
--cc=htejun@gmail.com \
--cc=jens.axboe@oracle.com \
--cc=linux-fsdevel@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-raid@vger.kernel.org \
--cc=psusi@cfl.rr.com \
--cc=ric@emc.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
all inboxes | Powered by JetHome®