From: Lee Revell <rlrevell@joe-job.com>
To: John Richard Moser <nigelenki@comcast.net>
Cc: linux-kernel@vger.kernel.org
Subject: Re: Kernel profiles anyone?
Date: Wed, 07 Sep 2005 00:26:55 -0400 [thread overview]
Message-ID: <1126067216.13159.44.camel@mindpipe> (raw)
In-Reply-To: <431E43C8.3030309@comcast.net>
On Tue, 2005-09-06 at 21:35 -0400, John Richard Moser wrote:
> -----BEGIN PGP SIGNED MESSAGE-----
> Hash: SHA1
>
> Are there any recent kernel profiles? I think from an acedemic
> perspective it'd be nice to see some graphs and numbers nobody
> understands showing where the longest running code paths in the kernel
> occur. It might also be nice for those latency whores (*runs to the
> back and raises hand*) and those who want to increase overall
> performance and efficiency; then there'd be a map showing . . .
> something that only kernel hackers could possibly understand or care about.
There's a latency histogram option in the -rt patch set. You can pipe
the output through gnuplot and get some cool graphs. Then you can
use /proc/latency_trace to try and guess what code paths the peaks on
the graphs correspond to. The timer interrupt will be the biggest peak,
around 23 usecs last time I checked.
I haven't done it lately so it would be interesting to see the current
graphs. Someone could make a really good presentation out of it at some
kernel development conference.
Lee
next prev parent reply other threads:[~2005-09-07 4:27 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2005-09-07 1:35 Kernel profiles anyone? John Richard Moser
2005-09-07 4:26 ` Lee Revell [this message]
2005-09-07 11:32 ` Neil Horman
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=1126067216.13159.44.camel@mindpipe \
--to=rlrevell@joe-job.com \
--cc=linux-kernel@vger.kernel.org \
--cc=nigelenki@comcast.net \
/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.