From: "Trenton D. Adams" <trenton.d.adams@gmail.com>
To: David Rees <drees76@gmail.com>
Cc: Christian Kujau <lists@nerdbynature.de>,
Artem Bityutskiy <Artem.Bityutskiy@nokia.com>,
Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: Re: EXT4-ish "fixes" in UBIFS
Date: Thu, 2 Apr 2009 21:14:00 -0600 [thread overview]
Message-ID: <9b1675090904022014t27e7f75ev1ca93cba94737c36@mail.gmail.com> (raw)
In-Reply-To: <9b1675090904022013t6c892b9bo91eab0fd7091bfbe@mail.gmail.com>
I'm really sorry, I just realized I hijacked this thread. I'll stop now.
On Thu, Apr 2, 2009 at 9:13 PM, Trenton D. Adams
<trenton.d.adams@gmail.com> wrote:
> On Thu, Apr 2, 2009 at 8:58 PM, David Rees <drees76@gmail.com> wrote:
>> On Thu, Apr 2, 2009 at 7:28 PM, Trenton D. Adams
>>> That's the odd thing, I was setting them to 2 and 1. I was just
>>> looking at the 2.6.29 code, and it should have made a difference. I
>>> don't know what version of the kernel I was using at the time. And,
>>> I'm not sure if I had the 1M fsync tests in place at the time either,
>>> to be sure about what I was testing. It could be that I wasn't being
>>> very scientific about it at the time. Thanks though, that setting
>>> makes a huge difference.
>>
>> Well, it depends on how much memory you have. Keep in mind that those
>> are percentages - so if you have 2GB RAM, that's the same as setting
>> it to 40MB and 20MB respectively - both are a lot larger than the 1M
>> you were setting the dirty*bytes vm knobs to.
>>
>> I've got a problematic server with 8GB RAM. Even if set both to 1,
>> that's 80MB and the crappy disks I have in it will often only write
>> 10-20MB/s or less due to the seekiness of the workload. That means
>> delays of 5-10 seconds worst case which isn't fun.
>>
>> -Dave
>>
>
> Yeah, I just finished doing the calculation. :P 40M is what I'm
> seeing. Yeah, that sounds like the same as my problem. Even setting
> it to 10M dirty_bytes has a very serious latency problem. I'm glad
> that option was added, because 1M works much better. I'll have to
> change my shell script to dynamically tune on that. Because under
> normal load, I want the 40M+ of queueing. It's just when things get
> really heavy, and stuff starts getting flushed, that this problem
> starts happening.
>
next prev parent reply other threads:[~2009-04-03 3:14 UTC|newest]
Thread overview: 45+ messages / expand[flat|nested] mbox.gz Atom feed top
2009-03-27 12:48 EXT4-ish "fixes" in UBIFS Artem Bityutskiy
2009-03-28 1:22 ` Kyungmin Park
2009-03-29 12:31 ` Artem Bityutskiy
2009-03-29 12:54 ` Artem Bityutskiy
2009-03-29 12:26 ` replace() system call needed (was Re: EXT4-ish "fixes" in UBIFS) Pavel Machek
2009-03-29 12:42 ` Artem Bityutskiy
2009-03-29 12:50 ` Pavel Machek
2009-03-29 13:00 ` Artem Bityutskiy
2009-03-29 13:02 ` Pavel Machek
2009-03-29 13:07 ` Artem Bityutskiy
2009-03-29 13:22 ` Andreas T.Auer
2009-03-29 13:55 ` Artem Bityutskiy
2009-03-29 13:40 ` Pavel Machek
2009-03-29 13:57 ` Artem Bityutskiy
2009-03-29 14:00 ` Pavel Machek
2009-03-30 17:19 ` Ric Wheeler
2009-03-30 22:11 ` Pavel Machek
2009-03-29 13:01 ` Andreas T.Auer
2009-03-29 13:06 ` Artem Bityutskiy
2009-03-30 15:58 ` Diego Calleja
2009-04-03 0:09 ` EXT4-ish "fixes" in UBIFS Christian Kujau
2009-04-03 0:24 ` Trenton D. Adams
2009-04-03 0:28 ` Trenton D. Adams
2009-04-03 0:38 ` Christian Kujau
2009-04-03 0:54 ` Trenton D. Adams
2009-04-03 0:54 ` Trenton D. Adams
2009-04-03 0:59 ` Trenton D. Adams
2009-04-03 1:55 ` David Rees
2009-04-03 2:05 ` Trenton D. Adams
2009-04-03 2:19 ` David Rees
2009-04-03 2:28 ` Trenton D. Adams
2009-04-03 2:58 ` David Rees
2009-04-03 3:13 ` Trenton D. Adams
2009-04-03 3:14 ` Trenton D. Adams [this message]
2009-04-03 5:02 ` Theodore Tso
2009-04-03 5:15 ` Trenton D. Adams
2009-04-03 6:30 ` Theodore Tso
2009-04-03 18:53 ` Chris Adams
2009-04-03 18:05 ` David Rees
2009-04-09 20:17 ` Pavel Machek
2009-04-03 2:26 ` Trenton D. Adams
2009-04-03 2:05 ` Theodore Tso
2009-04-03 2:45 ` Christian Kujau
2009-04-03 2:49 ` Trenton D. Adams
2009-04-03 6:53 ` Artem Bityutskiy
[not found] <cmFiD-8uc-9@gated-at.bofh.it>
[not found] ` <cmFss-ft-15@gated-at.bofh.it>
[not found] ` <cmFsu-ft-23@gated-at.bofh.it>
[not found] ` <cmGRt-2hq-7@gated-at.bofh.it>
[not found] ` <cmH1b-2K0-11@gated-at.bofh.it>
[not found] ` <cmHkz-3d3-5@gated-at.bofh.it>
[not found] ` <cmHkA-3d3-7@gated-at.bofh.it>
[not found] ` <cmHND-3Oz-5@gated-at.bofh.it>
[not found] ` <cmJPm-7hd-5@gated-at.bofh.it>
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=9b1675090904022014t27e7f75ev1ca93cba94737c36@mail.gmail.com \
--to=trenton.d.adams@gmail.com \
--cc=Artem.Bityutskiy@nokia.com \
--cc=drees76@gmail.com \
--cc=linux-kernel@vger.kernel.org \
--cc=lists@nerdbynature.de \
/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).