From: Fabrice Bellard <fabrice@bellard.org>
To: qemu-devel@nongnu.org
Cc: Chris Wright <chrisw@redhat.com>,
Mark McLoughlin <markmc@redhat.com>,
Ryan Harper <ryanh@us.ibm.com>,
Laurent Vivier <Laurent.Vivier@bull.net>,
kvm-devel <kvm-devel@lists.sourceforge.net>
Subject: Re: [Qemu-devel] [RFC] Disk integrity in QEMU
Date: Fri, 10 Oct 2008 12:03:25 +0200 [thread overview]
Message-ID: <48EF286D.3050200@bellard.org> (raw)
In-Reply-To: <48EE38B9.2050106@codemonkey.ws>
Anthony Liguori wrote:
> [...]
> So to summarize, I think we should enable O_DSYNC by default to ensure
> that guest data integrity is not dependent on the host OS, and that
> practically speaking, cache=off is only useful for very specialized
> circumstances. Part of the patch I'll follow up with includes changes
> to the man page to document all of this for users.
>
> Thoughts?
QEMU is also used for debugging and arbitrary machine simulation. In
this case, using uncached accesses is bad because you want maximum
isolation between the guest and the host. For example, if the guest is a
development OS not using a disk cache, I still want to use the host disk
cache.
So the "normal" caching scheme must be left as it is now. However, I
agree that the default behavior could be modified.
Regards,
Fabrice.
next prev parent reply other threads:[~2008-10-10 10:03 UTC|newest]
Thread overview: 101+ messages / expand[flat|nested] mbox.gz Atom feed top
2008-10-09 17:00 [Qemu-devel] [RFC] Disk integrity in QEMU Anthony Liguori
2008-10-10 7:54 ` Gerd Hoffmann
2008-10-10 8:12 ` Mark McLoughlin
2008-10-12 23:10 ` Jamie Lokier
2008-10-14 17:15 ` Avi Kivity
2008-10-10 9:32 ` Avi Kivity
2008-10-12 23:00 ` Jamie Lokier
2008-10-10 8:11 ` Aurelien Jarno
2008-10-10 12:26 ` Anthony Liguori
2008-10-10 12:53 ` Paul Brook
2008-10-10 13:55 ` Anthony Liguori
2008-10-10 14:05 ` Paul Brook
2008-10-10 14:19 ` Avi Kivity
2008-10-17 13:14 ` Jens Axboe
2008-10-19 9:13 ` Avi Kivity
2008-10-10 15:48 ` Aurelien Jarno
2008-10-10 9:16 ` Avi Kivity
2008-10-10 9:58 ` Daniel P. Berrange
2008-10-10 10:26 ` Avi Kivity
2008-10-10 12:59 ` Paul Brook
2008-10-10 13:20 ` Avi Kivity
2008-10-10 12:34 ` Anthony Liguori
2008-10-10 12:56 ` Avi Kivity
2008-10-11 9:07 ` andrzej zaborowski
2008-10-11 17:54 ` Mark Wagner
2008-10-11 20:35 ` Anthony Liguori
2008-10-12 0:43 ` Mark Wagner
2008-10-12 1:50 ` Chris Wright
2008-10-12 16:22 ` Jamie Lokier
2008-10-12 17:54 ` Anthony Liguori
2008-10-12 18:14 ` nuitari-qemu
2008-10-13 0:27 ` Mark Wagner
2008-10-13 1:21 ` Anthony Liguori
2008-10-13 2:09 ` Mark Wagner
2008-10-13 3:16 ` Anthony Liguori
2008-10-13 6:42 ` Aurelien Jarno
2008-10-13 14:38 ` Steve Ofsthun
2008-10-12 0:44 ` Chris Wright
2008-10-12 10:21 ` Avi Kivity
2008-10-12 14:37 ` Dor Laor
2008-10-12 15:35 ` Jamie Lokier
2008-10-12 18:00 ` Anthony Liguori
2008-10-12 18:02 ` Anthony Liguori
2008-10-15 10:17 ` Andrea Arcangeli
2008-10-12 17:59 ` Anthony Liguori
2008-10-12 18:34 ` Avi Kivity
2008-10-12 19:33 ` Izik Eidus
2008-10-14 17:08 ` Avi Kivity
2008-10-12 19:59 ` Anthony Liguori
2008-10-12 20:43 ` Avi Kivity
2008-10-12 21:11 ` Anthony Liguori
2008-10-14 15:21 ` Avi Kivity
2008-10-14 15:32 ` Anthony Liguori
2008-10-14 15:43 ` Avi Kivity
2008-10-14 19:25 ` Laurent Vivier
2008-10-16 9:47 ` Avi Kivity
2008-10-12 10:12 ` Avi Kivity
2008-10-17 13:20 ` Jens Axboe
2008-10-19 9:01 ` Avi Kivity
2008-10-19 18:10 ` Jens Axboe
2008-10-19 18:23 ` Avi Kivity
2008-10-19 19:17 ` M. Warner Losh
2008-10-19 19:31 ` Avi Kivity
2008-10-19 18:24 ` Avi Kivity
2008-10-19 18:36 ` Jens Axboe
2008-10-19 19:11 ` Avi Kivity
2008-10-19 19:30 ` Jens Axboe
2008-10-19 20:16 ` Avi Kivity
2008-10-20 14:14 ` Avi Kivity
2008-10-10 10:03 ` Fabrice Bellard [this message]
2008-10-13 16:11 ` Laurent Vivier
2008-10-13 16:58 ` Anthony Liguori
2008-10-13 17:36 ` Jamie Lokier
2008-10-13 17:06 ` [Qemu-devel] " Ryan Harper
2008-10-13 18:43 ` Anthony Liguori
2008-10-14 16:42 ` Avi Kivity
2008-10-13 18:51 ` Laurent Vivier
2008-10-13 19:43 ` Ryan Harper
2008-10-13 20:21 ` Laurent Vivier
2008-10-13 21:05 ` Ryan Harper
2008-10-15 13:10 ` Laurent Vivier
2008-10-16 10:24 ` Laurent Vivier
2008-10-16 13:43 ` Anthony Liguori
2008-10-16 16:08 ` Laurent Vivier
2008-10-17 12:48 ` Avi Kivity
2008-10-17 13:17 ` Laurent Vivier
2008-10-14 10:05 ` Kevin Wolf
2008-10-14 14:32 ` Ryan Harper
2008-10-14 16:37 ` Avi Kivity
2008-10-13 19:00 ` Mark Wagner
2008-10-13 19:15 ` Ryan Harper
2008-10-14 16:49 ` Avi Kivity
2008-10-13 17:58 ` [Qemu-devel] " Rik van Riel
2008-10-13 18:22 ` Jamie Lokier
2008-10-13 18:34 ` Rik van Riel
2008-10-14 1:56 ` Jamie Lokier
2008-10-14 2:28 ` nuitari-qemu
2008-10-28 17:34 ` Ian Jackson
2008-10-28 17:45 ` Anthony Liguori
2008-10-28 17:50 ` Ian Jackson
2008-10-28 18:19 ` Jamie Lokier
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=48EF286D.3050200@bellard.org \
--to=fabrice@bellard.org \
--cc=Laurent.Vivier@bull.net \
--cc=chrisw@redhat.com \
--cc=kvm-devel@lists.sourceforge.net \
--cc=markmc@redhat.com \
--cc=qemu-devel@nongnu.org \
--cc=ryanh@us.ibm.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).