From: Mark Lord <lkml@rtr.ca>
To: Jeff Gold <jgold@mazunetworks.com>
Cc: linux-kernel@vger.kernel.org
Subject: Re: Serial Console and Slow SCSI Disk Access?
Date: Mon, 12 Jun 2006 17:39:41 -0400 [thread overview]
Message-ID: <448DDF1D.5020108@rtr.ca> (raw)
In-Reply-To: <448DDC7F.4030308@mazunetworks.com>
Jeff Gold wrote:
> Does it make sense that enabling a serial console would reduce the
> bandwidth of a SCSI disk by more than a factor of ten? This seems crazy
> to me but there's no arguing with empirical facts. I have an IBM x345
> system on which I installed an unmodified 2.6.16.20 kernel built with
> gcc-4.0.2-8.fc4 (the kernel configuration file I used can be found at
> http://augart.com/jgold/kconfig). With the control kernel command line
> I get about 70 MB/sec with hdparm -t but when I add "console=ttyS0,9600
> console=tty0" I get about 1.6 MB/sec instead.
This can happen if there are kernel messages being printed on the serial console.
If all is quiet, I would expect things to be as fast as normal elsewhere.
-ml
next prev parent reply other threads:[~2006-06-12 21:39 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2006-06-12 21:28 Serial Console and Slow SCSI Disk Access? Jeff Gold
2006-06-12 21:39 ` Mark Lord [this message]
2006-06-12 22:04 ` Jeff Gold
2006-06-19 6:50 ` Helge Hafting
2006-06-19 15:14 ` Jeff Gold
2006-06-20 7:11 ` Helge Hafting
2006-06-20 16:20 ` Jeff Gold
2006-06-22 0:32 ` David Lang
2006-06-22 16:18 ` Andrey Melnikoff
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=448DDF1D.5020108@rtr.ca \
--to=lkml@rtr.ca \
--cc=jgold@mazunetworks.com \
--cc=linux-kernel@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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.