From: Greg Banks <gnb@sgi.com>
To: Dongjun Shin <djshin90@gmail.com>
Cc: Linux Filesystem Mailing List <linux-fsdevel@vger.kernel.org>,
David Chinner <dgc@melbourne.sgi.com>,
Donald Douwsma <donaldd@melbourne.sgi.com>,
Christoph Hellwig <hch@infradead.org>,
Roger Strassburg <rls@sgi.com>, Mark Goodwin <markgw@sgi.com>,
Brett Jon Grandbois <brettg@melbourne.sgi.com>,
Arnd Bergmann <arnd@arndb.de>
Subject: Re: Proposal to improve filesystem/block snapshot interaction
Date: Wed, 31 Oct 2007 14:44:36 +1100 [thread overview]
Message-ID: <20071031034436.GB9041@sgi.com> (raw)
In-Reply-To: <7fe698080710300235v3ce49613nfe3c5e733f1b6f5b@mail.gmail.com>
On Tue, Oct 30, 2007 at 06:35:08PM +0900, Dongjun Shin wrote:
> On 10/30/07, Greg Banks <gnb@sgi.com> wrote:
> >
> > BIO_HINT_RELEASE
> > The bio's block extent is no longer in use by the filesystem
> > and will not be read in the future. Any storage used to back
> > the extent may be released without any threat to filesystem
> > or data integrity.
> >
>
> I'd like to second the proposal, but it would be more useful to bring the hint
> down to the physical devices.
>
> There is an ongoing discussion about adding 'Trim' ATA command for notifying
> the drive about the deleted blocks.
>
> http://www.t13.org/Documents/UploadedDocuments/docs2007/e07154r3-Data_Set_Management_Proposal_for_ATA-ACS2.pdf
What an interesting document. Am I reading the change markup correctly,
did it get *simpler* in the last revision? Wow.
I agree that BIO_HINT_RELEASE would be a good match for the proposed
Trim command. But I don't think we'll ever be issuing Trims with
more than a single LBA Range Entry, that feature seems unhelpful.
The Trim proposal doesn't specify what happens when a sector which
is already deallocated is deallocated again, presumably this is
supposed to be harmless?
Greg.
--
Greg Banks, R&D Software Engineer, SGI Australian Software Group.
Apparently, I'm Bedevere. Which MPHG character are you?
I don't speak for SGI.
prev parent reply other threads:[~2007-10-31 3:36 UTC|newest]
Thread overview: 20+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <20070927063113.GD2989@sgi.com>
2007-10-30 1:04 ` Proposal to improve filesystem/block snapshot interaction Greg Banks
2007-10-30 1:11 ` Greg Banks
2007-10-30 4:16 ` Neil Brown
2007-10-30 5:12 ` Greg Banks
2007-10-30 7:43 ` Arnd Bergmann
2007-11-20 23:43 ` Roger Strassburg
2007-10-30 23:56 ` David Chinner
2007-10-31 4:01 ` Greg Banks
2007-10-31 7:04 ` David Chinner
2007-10-30 9:35 ` Dongjun Shin
2007-10-30 10:15 ` Arnd Bergmann
2007-10-30 10:49 ` Dongjun Shin
2007-10-30 12:38 ` Arnd Bergmann
2007-10-30 14:19 ` Dongjun Shin
2007-10-30 15:37 ` Jörn Engel
2007-10-30 16:37 ` Arnd Bergmann
2007-10-30 23:19 ` Kyungmin Park
2007-10-30 23:42 ` Kyungmin Park
2007-10-30 14:06 ` Jörn Engel
2007-10-31 3:44 ` Greg Banks [this message]
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=20071031034436.GB9041@sgi.com \
--to=gnb@sgi.com \
--cc=arnd@arndb.de \
--cc=brettg@melbourne.sgi.com \
--cc=dgc@melbourne.sgi.com \
--cc=djshin90@gmail.com \
--cc=donaldd@melbourne.sgi.com \
--cc=hch@infradead.org \
--cc=linux-fsdevel@vger.kernel.org \
--cc=markgw@sgi.com \
--cc=rls@sgi.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).