From: Jeff Dike <jdike@karaya.com>
To: Ryan Cumming <bodnar42@phalynx.dhs.org>
Cc: linux-kernel@vger.kernel.org
Subject: Re: Special Kernel Modification
Date: Mon, 05 Nov 2001 00:52:51 -0500 [thread overview]
Message-ID: <200111050552.AAA06451@ccure.karaya.com> (raw)
In-Reply-To: Your message of "Sun, 04 Nov 2001 19:13:15 PST." <E160aCK-0001Fs-00@localhost>
bodnar42@phalynx.dhs.org said:
> > Mounting it synchronous will disable caching in the VM.
> Who told
> you that? Synchronous mounting turns off write buffering. Even with
> "-o sync" writes will still end up in the page cache, they'll just be
> commited immediately.
Ummm, how about O_DIRECT instead of O_SYNC (or maybe as well, my googling
hasn't been clear on whether O_DIRECT bypasses the cache on writes as well)?
All IO bypasses the virtual machine cache, so there's no multiple caching.
> Er, it will be shared in the host's context, but each VM will still
> have their own copy in the page cache. This is no better than a
> COW'ed block device
Nope. You O_DIRECT here as well.
Jeff
next prev parent reply other threads:[~2001-11-05 4:34 UTC|newest]
Thread overview: 23+ messages / expand[flat|nested] mbox.gz Atom feed top
2001-11-05 0:01 Special Kernel Modification Lonnie Cumberland
2001-11-05 0:19 ` Ryan Cumming
2001-11-05 0:29 ` lonnie
2001-11-05 1:04 ` Jan-Benedict Glaw
2001-11-05 3:04 ` Mike Fedyk
2001-11-06 0:34 ` Jorgen Cederlof
2001-11-06 0:38 ` lonnie
2001-11-05 0:22 ` Alan Cox
2001-11-05 0:39 ` Phil Sorber
2001-11-05 0:38 ` Rik van Riel
2001-11-05 1:04 ` Jeremy Jackson
2001-11-05 1:58 ` Jeff Dike
2001-11-05 2:14 ` Ryan Cumming
2001-11-05 4:02 ` Jeff Dike
2001-11-05 3:13 ` Ryan Cumming
2001-11-05 5:52 ` Jeff Dike [this message]
2001-11-05 5:30 ` Ryan Cumming
2001-11-05 14:22 ` Jeff Dike
2001-11-05 16:53 ` Andrea Arcangeli
2001-11-05 20:18 ` Jeff Dike
2001-11-05 19:05 ` Andrea Arcangeli
-- strict thread matches above, loose matches on Subject: below --
2001-11-05 0:37 John Weber
[not found] <E160aCK-0001Fs-00@localhost.suse.lists.linux.kernel>
[not found] ` <200111050552.AAA06451@ccure.karaya.com.suse.lists.linux.kernel>
2001-11-05 6:22 ` Andi Kleen
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=200111050552.AAA06451@ccure.karaya.com \
--to=jdike@karaya.com \
--cc=bodnar42@phalynx.dhs.org \
--cc=linux-kernel@vger.kernel.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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.