From: Stefan Priebe <s.priebe@profihost.ag>
To: Andrey Korolyov <andrey@xdel.ru>
Cc: ceph-devel@vger.kernel.org
Subject: Re: how to debug slow rbd block device
Date: Tue, 22 May 2012 21:27:10 +0200 [thread overview]
Message-ID: <4FBBE88E.1000904@profihost.ag> (raw)
In-Reply-To: <CABYiri_A-Ge6nQMG5NJuwj3h=vFYJmhj9LzdfPdWe_SRMCrx-w@mail.gmail.com>
Am 22.05.2012 16:52, schrieb Andrey Korolyov:
> Hi,
>
> I`ve run in almost same problem about two months ago, and there is a
> couple of corner cases: near-default tcp parameters, small journal
> size, disks that are not backed by controller with NVRAM cache and
> high load on osd` cpu caused by side processes. Finally, I have able
> to achieve 115Mb/s for large linear writes on raw rbd block inside VM
> with journal on tmpfs and osds on RAID0 built on top of three sata
> disks.
which tcp parameters could you recommand? The journal size is 1Gb on
tmpfs right now. Instead of 3 sata disks i'm using one intel ssd. the
CPU is loaded by 10% on each osd max. A "ceph osd tell X bench" shows me
260MB/s write on each OSD (intel ssd).
Greets
Stefan
next prev parent reply other threads:[~2012-05-22 19:27 UTC|newest]
Thread overview: 27+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-05-22 12:45 how to debug slow rbd block device Stefan Priebe - Profihost AG
2012-05-22 14:52 ` Andrey Korolyov
2012-05-22 19:27 ` Stefan Priebe [this message]
2012-05-22 19:35 ` Greg Farnum
2012-05-22 19:40 ` Stefan Priebe
2012-05-22 19:52 ` Greg Farnum
2012-05-22 20:13 ` Stefan Priebe
2012-05-22 20:30 ` Stefan Priebe
2012-05-22 20:48 ` Mark Nelson
2012-05-22 20:54 ` Stefan Priebe
2012-05-22 20:49 ` Greg Farnum
2012-05-22 21:00 ` Stefan Priebe
2012-05-22 21:11 ` Greg Farnum
2012-05-23 6:18 ` Stefan Priebe - Profihost AG
2012-05-23 6:30 ` Josh Durgin
2012-05-23 7:01 ` Stefan Priebe - Profihost AG
2012-05-23 7:19 ` Josh Durgin
2012-05-23 7:22 ` Stefan Priebe - Profihost AG
2012-05-23 7:33 ` Josh Durgin
[not found] ` <CABYiri8PXT9dpCGLE7dn=_PoW8CdLxqZF87OHe=dMXEWxogb_w@mail.gmail.com>
2012-05-23 19:54 ` Josh Durgin
2012-05-23 8:20 ` Stefan Priebe - Profihost AG
2012-05-23 8:29 ` Josh Durgin
2012-05-23 7:22 ` Andrey Korolyov
2012-05-23 8:15 ` Stefan Priebe - Profihost AG
2012-05-23 11:47 ` Mark Nelson
2012-05-23 8:30 ` Stefan Priebe - Profihost AG
2012-05-23 9:10 ` Stefan Priebe - Profihost AG
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=4FBBE88E.1000904@profihost.ag \
--to=s.priebe@profihost.ag \
--cc=andrey@xdel.ru \
--cc=ceph-devel@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