From: Chris Mason <mason@suse.com>
To: "Dieter Nützel" <Dieter.Nuetzel@hamburg.de>
Cc: ReiserFS List <reiserfs-list@namesys.com>
Subject: Re: data-logging on top of linux-2.4.19p7-compound-speedup-2.patch
Date: 20 May 2002 09:46:09 -0400 [thread overview]
Message-ID: <1021902370.22608.17.camel@tiny> (raw)
In-Reply-To: <200205172204.22469.Dieter.Nuetzel@hamburg.de>
On Fri, 2002-05-17 at 16:04, Dieter Nützel wrote:
> So data=journal is very slow for me.
> What's wrong?
Nothing ;-) data=journal writes every data block twice, opnce to the
log and once to the main disk. Most of the time this makes things
roughly 1/2 as fast as it was before.
The only time data=journal helps is when you've got a very fsync or
O_SYNC heavy application. Try running iozone with -o on both
data=journal and without it, data=journal is 2 or 3 times as fast.
This is because we can do the sync by writing to the log instead of
writing to the log and having to seek back to the main disk.
-chris
next prev parent reply other threads:[~2002-05-20 13:46 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <200205040219.42912.Dieter.Nuetzel@hamburg.de>
[not found] ` <1020608683.1510.1353.camel@tiny>
2002-05-17 20:04 ` data-logging on top of linux-2.4.19p7-compound-speedup-2.patch Dieter Nützel
2002-05-20 13:46 ` Chris Mason [this message]
2002-05-20 14:08 ` Dieter Nützel
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=1021902370.22608.17.camel@tiny \
--to=mason@suse.com \
--cc=Dieter.Nuetzel@hamburg.de \
--cc=reiserfs-list@namesys.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 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.