From: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
To: Carlo Wood <carlo@alinoe.com>
Cc: Jeff Garzik <jeff@garzik.org>, Tejun Heo <htejun@gmail.com>,
Manoj Kasichainula <manoj@io.com>,
linux-kernel@vger.kernel.org,
IDE/ATA development list <linux-ide@vger.kernel.org>
Subject: Re: SATA RAID5 speed drop of 100 MB/s
Date: Sat, 23 Jun 2007 19:30:57 +0200 [thread overview]
Message-ID: <200706231930.57688.bzolnier@gmail.com> (raw)
In-Reply-To: <20070623125316.GB26672@alinoe.com>
Hi,
On Saturday 23 June 2007, Carlo Wood wrote:
> PS I'd like to do extensive testing with Bonnie++ to tune everything
> there is to tune. But bonnie likes to write/read files TWICE the amount
> of RAM I have. It therefore takes a LOT of time to run one test. Do you
> happen to know how I can limit the amount of RAM that the linux kernel
> sees to, say 500 MB? That should be enough to run in Single User mode
> but allow me to run the tests MUCH faster. (I have dual channel, four
> DIMM's of 1 GB each -- 2 GB per Core 2 die. Hopefully the fact that
> I have dual channel isn't going to be a problem when limiting the ram
> that the kernel sees.)
"mem=" kernel parameter limits amount of memory seen by kernel
(more info in Documentation/kernel-parameters.txt)
You can also limit amount of RAM detected by bonnie++ by using -r parameter
but please remember that this will make bonnie++ benchmark combined kernel
I/O buffering + filesystem + hard disk performance instead of just filesystem
+ hard disk performance (as it can happen that some / all data won't ever
hit the disk).
Bart
next prev parent reply other threads:[~2007-06-23 17:52 UTC|newest]
Thread overview: 31+ messages / expand[flat|nested] mbox.gz Atom feed top
2007-06-20 22:48 SATA Harddisk speed drop of 100 MB/s Carlo Wood
2007-06-20 23:06 ` Jeff Garzik
2007-06-21 3:36 ` Arjan van de Ven
2007-06-22 16:21 ` Carlo Wood
2007-06-22 21:17 ` Henrique de Moraes Holschuh
2007-06-22 21:27 ` Carlo Wood
2007-06-23 1:31 ` Henrique de Moraes Holschuh
2007-06-23 2:59 ` Carlo Wood
2007-06-23 17:29 ` Andrew Morton
2007-06-23 22:21 ` Jeff Garzik
2007-06-25 15:18 ` Lennart Sorensen
2007-06-25 16:04 ` Carlo Wood
2007-06-22 21:44 ` SATA RAID5 " Carlo Wood
2007-06-23 3:54 ` Carlo Wood
2007-06-23 6:22 ` Tejun Heo
2007-06-22 21:48 ` Carlo Wood
2007-06-23 7:03 ` Jeff Garzik
2007-06-23 7:54 ` Tejun Heo
2007-06-23 12:53 ` Carlo Wood
2007-06-23 17:30 ` Bartlomiej Zolnierkiewicz [this message]
2007-06-23 22:43 ` Jeff Garzik
2007-06-24 11:58 ` Michael Tokarev
2007-06-24 12:59 ` Dr. David Alan Gilbert
2007-06-24 14:21 ` Justin Piszcz
2007-06-24 15:52 ` Michael Tokarev
2007-06-24 16:59 ` Justin Piszcz
2007-06-24 22:07 ` Carlo Wood
2007-06-24 23:46 ` Mark Lord
2007-06-25 0:23 ` Patrick Mau
2007-06-24 15:48 ` Michael Tokarev
2007-07-05 22:12 ` Phillip Susi
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=200706231930.57688.bzolnier@gmail.com \
--to=bzolnier@gmail.com \
--cc=carlo@alinoe.com \
--cc=htejun@gmail.com \
--cc=jeff@garzik.org \
--cc=linux-ide@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=manoj@io.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).