From: youagree <n3ocort3x@gmail.com>
To: linux-btrfs@vger.kernel.org
Subject: Re: Rename BTRfs to MuchSlowerFS ?
Date: Thu, 08 Sep 2011 09:04:25 +0200 [thread overview]
Message-ID: <j49p85$f41$1@dough.gmane.org> (raw)
In-Reply-To: <20110905162944.GQ9907@carfax.org.uk>
On 09/05/2011 06:29 PM, Hugo Mills wrote:
> On Mon, Sep 05, 2011 at 12:25:21PM -0400, Christoph Hellwig wrote:
>> On Mon, Sep 05, 2011 at 06:23:23PM +0200, Tomasz Chmielewski wrote:
>>>> That's because dpkg is known for using (f)sync very heavily. btrfs
>>>> honours the sync request in all cases, so it's much much slower than
>>>> ext3, which doesn't.
>>>
>>> Hmm, is it really the case with ext3/ext4 (ignoring fsync in some cases)?
>>>
>>> Sounds like a bug in ext3/ext4 then.
>>>
>>> Is it documented anywhere where ext3/ext4 would just silently ignore fsync?
>>
>> They don't. Unteil recently ext3 and reiserfs would not flush the
>> disk caches unless enabled by a mount option, but even that has recently
>> been fixed.
>
> Apologies for disseminating my misunderstanding, then.
>
> Hugo.
>
I'm wondering if this may be the very same unacceptable behavior as
discussed earlier also in the following message threads:
btrfs always writes something after sync
news://news.gmane.org:119/CABVOS09hntXYUsCJBg+byEGC5y53j4DeT6b49Rx1AaRpqFV54A@mail.gmail.com
Re: Writes in idle/How to debug filesystem activity
news://news.gmane.org:119/4E5C8A20.7030604@wpkg.org
Re: Applications using fsync cause hangs for several seconds every few
minutes
news://news.gmane.org:119/4E41A6A4.9070702@uvm.edu
Btrfs slowdown
news://news.gmane.org:119/CAO47_-9BLKWUGDEuzaLqHSq9tZkAUaO8FMQEy1pPk9A2Hb+5AQ@mail.gmail.com
PLEASE TEST: Everybody who is seeing weird and long hangs
news://news.gmane.org:119/4E36C47E.70309@redhat.com
and this:
curious writes on mounted, not used btrfs filesystem
http://thread.gmane.org/gmane.comp.file-systems.btrfs/10840
and probably this:
2.6.37: Multi-second I/O latency while untarring
http://www.spinics.net/lists/linux-btrfs/msg08516.html
Hasn't the slowdown been fixed yet?
For those experiencing the slowdown issue btrfs is entirely useless...
(I had to stop using btrfs because of these frequent slowdowns, while
btrfs was doing most likely needless disk writes for multiple seconds, I
couldn't work at all)
Can someone look into this if this is not fixed? There are numerous
analysis reports in the above threads, without any constructive result.
Thanks
next prev parent reply other threads:[~2011-09-08 7:04 UTC|newest]
Thread overview: 18+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-09-05 16:23 Rename BTRfs to MuchSlowerFS ? Tomasz Chmielewski
2011-09-05 16:25 ` Christoph Hellwig
2011-09-05 16:29 ` Hugo Mills
2011-09-08 7:04 ` youagree [this message]
-- strict thread matches above, loose matches on Subject: below --
2011-09-05 13:51 Swâmi Petaramesh
2011-09-05 14:00 ` Hugo Mills
2011-09-05 14:20 ` Roman Mamedov
2011-09-05 17:10 ` Elric Milon
2011-09-05 14:17 ` David McBride
2011-09-05 19:25 ` Sergei Trofimovich
2011-09-06 15:30 ` Swâmi Petaramesh
2011-09-06 17:11 ` Fajar A. Nugraha
2011-09-07 14:15 ` Swâmi Petaramesh
2011-09-15 19:37 ` Felix Blanke
2011-09-15 22:16 ` Fajar A. Nugraha
2011-09-16 6:21 ` Maciej Marcin Piechotka
2011-09-16 6:42 ` Fajar A. Nugraha
2011-09-16 8:39 ` Maciej Marcin Piechotka
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='j49p85$f41$1@dough.gmane.org' \
--to=n3ocort3x@gmail.com \
--cc=linux-btrfs@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 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).