From: Christoph Hellwig <hch@lst.de>
To: Chris Wedgwood <cw@f00f.org>
Cc: pbonzini@redhat.com, aliguori@us.ibm.com,
Michael Roth <mdroth@linux.vnet.ibm.com>,
qemu-devel@nongnu.org
Subject: Re: [Qemu-devel] [PATCH 2/2] qemu-ga: add guest-fstrim command
Date: Sun, 24 Jun 2012 18:33:40 +0200 [thread overview]
Message-ID: <20120624163340.GA5727@lst.de> (raw)
In-Reply-To: <20120622174856.GA6505@puku.stupidest.org>
On Fri, Jun 22, 2012 at 10:48:56AM -0700, Chris Wedgwood wrote:
> > FITRIM is a mounted filesystem feature to discard (or "trim") blocks which
> > are not in use by the filesystem. This is useful for solid-state drives
> > (SSDs) and thinly-provisioned storage. Provide access to the feature
> > from the host so that filesystems can be trimmed periodically or before
> > migration.
>
> Why can't we use the block layer for this? AHCI (I think) already
> has support, others could be added some some coordination.
>
> That was existing operating systems with current filesystems will DTRT
> when needed.
This commands calls the FITRIM command in the guest, which tells the
filesystems to issue an discard for all currently unused space. At that
point it enters the block layer.
next prev parent reply other threads:[~2012-06-24 16:33 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-06-21 23:04 [Qemu-devel] [PULL] qemu-ga patches for guest-fstrim command Michael Roth
2012-06-21 23:04 ` [Qemu-devel] [PATCH 1/2] qemu-ga: make names more generic for mount list functions Michael Roth
2012-06-21 23:04 ` [Qemu-devel] [PATCH 2/2] qemu-ga: add guest-fstrim command Michael Roth
2012-06-22 17:48 ` Chris Wedgwood
2012-06-22 21:12 ` Michael Roth
2012-06-23 3:38 ` Chris Wedgwood
2012-06-23 20:54 ` Michael Roth
2012-06-24 16:33 ` Christoph Hellwig [this message]
-- strict thread matches above, loose matches on Subject: below --
2012-06-12 10:50 [Qemu-devel] [PATCH 0/2] qemu-ga: Add " Paolo Bonzini
2012-06-12 10:50 ` [Qemu-devel] [PATCH 2/2] qemu-ga: add " Paolo Bonzini
2012-06-12 19:54 ` Luiz Capitulino
2012-06-12 21:05 ` Michael Roth
2012-06-13 5:31 ` Paolo Bonzini
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=20120624163340.GA5727@lst.de \
--to=hch@lst.de \
--cc=aliguori@us.ibm.com \
--cc=cw@f00f.org \
--cc=mdroth@linux.vnet.ibm.com \
--cc=pbonzini@redhat.com \
--cc=qemu-devel@nongnu.org \
/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).