From: Phillip Susi <psusi@ubuntu.com>
To: stan@hardwarefreak.com, Marc MERLIN <marc@merlins.org>
Cc: linux-raid@vger.kernel.org
Subject: Re: Very long raid5 init/rebuild times
Date: Sun, 02 Feb 2014 13:53:57 -0500 [thread overview]
Message-ID: <52EE9445.2020202@ubuntu.com> (raw)
In-Reply-To: <52ED77A3.6020509@hardwarefreak.com>
-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA512
On 02/01/2014 05:39 PM, Stan Hoeppner wrote:
> Phillip, you seem to be arguing application performance. For an
> application/data type that doesn't need fsync you'd be correct.
>
> However, the purpose of this exchange has been to determine the
> maximum hardware throughput of the OP's array. It's not possible
> to accurately measure IO throughput doing buffered writes. Thus
> O_DIRECT is needed.
No, you can get there just fine with buffered IO as well, unless you
have an obscenely fast array and very slow ram, the overhead of
buffering won't really matter for IO throughput ( just the extra cpu ).
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.14 (GNU/Linux)
Comment: Using GnuPG with Thunderbird - http://www.enigmail.net/
iQEcBAEBCgAGBQJS7pRFAAoJEI5FoCIzSKrw/5AH/2EUXwPjdaqKyg9oD5igX92p
VLLjCCDJyzd2MaC3u4DPpQUtzIXPEkjuKT6hBMNwx/+gFnODXQjssZ3siXVgc2Mi
JAGYwRWYbLDYQscKagYyQFDiNjg5b1zA/KEjKYTO5hpkFQELDgE115PPn6NhV/Q9
r/vjzEtvDLjuN5Y7uQDpZv87bEy2O7aJX1TFygPN0MazJo6O93yFfweUwI2JUm1H
q1DL96Evd/CCfzhPWiPnWrP4MpuUG7B1OKjwfXnlw5tW1tj7wRA6tRnyuCeAHCfb
1/wvxXm426rxflSNa85sP///amh8mnccN+4ZcOYEql4XSt8qh8G2sdH35Kp3og8=
=BnZb
-----END PGP SIGNATURE-----
next prev parent reply other threads:[~2014-02-02 18:53 UTC|newest]
Thread overview: 41+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-01-21 7:35 Very long raid5 init/rebuild times Marc MERLIN
2014-01-21 16:37 ` Marc MERLIN
2014-01-21 17:08 ` Mark Knecht
2014-01-21 18:42 ` Chris Murphy
2014-01-22 7:55 ` Stan Hoeppner
2014-01-22 17:48 ` Marc MERLIN
2014-01-22 23:17 ` Stan Hoeppner
2014-01-23 14:28 ` John Stoffel
2014-01-24 1:02 ` Stan Hoeppner
2014-01-24 3:07 ` NeilBrown
2014-01-24 8:24 ` Stan Hoeppner
2014-01-23 2:37 ` Stan Hoeppner
2014-01-23 9:13 ` Marc MERLIN
2014-01-23 12:24 ` Stan Hoeppner
2014-01-23 21:01 ` Marc MERLIN
2014-01-24 5:13 ` Stan Hoeppner
2014-01-25 8:36 ` Marc MERLIN
2014-01-28 7:46 ` Stan Hoeppner
2014-01-28 16:50 ` Marc MERLIN
2014-01-29 0:56 ` Stan Hoeppner
2014-01-29 1:01 ` Marc MERLIN
2014-01-30 20:47 ` Phillip Susi
2014-02-01 22:39 ` Stan Hoeppner
2014-02-02 18:53 ` Phillip Susi [this message]
2014-02-03 6:34 ` Stan Hoeppner
2014-02-03 14:42 ` Phillip Susi
2014-02-04 3:30 ` Stan Hoeppner
2014-02-04 17:59 ` Larry Fenske
2014-02-04 18:08 ` Phillip Susi
2014-02-04 18:43 ` Stan Hoeppner
2014-02-04 18:55 ` Phillip Susi
2014-02-04 19:15 ` Stan Hoeppner
2014-02-04 20:16 ` Phillip Susi
2014-02-04 21:58 ` Stan Hoeppner
2014-02-05 1:19 ` Phillip Susi
2014-02-05 1:42 ` Stan Hoeppner
2014-01-30 20:36 ` Phillip Susi
2014-01-30 20:18 ` Phillip Susi
2014-01-22 19:38 ` Opal 2.0 SEDs on linux, was: " Chris Murphy
2014-01-21 18:31 ` Chris Murphy
2014-01-22 13:46 ` Ethan Wilson
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=52EE9445.2020202@ubuntu.com \
--to=psusi@ubuntu.com \
--cc=linux-raid@vger.kernel.org \
--cc=marc@merlins.org \
--cc=stan@hardwarefreak.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 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).