From: Nick Piggin <nickpiggin@yahoo.com.au>
To: linux-ia64@vger.kernel.org
Subject: Re: Volanomark regress on ia64
Date: Sun, 18 Sep 2005 10:56:31 +0000 [thread overview]
Message-ID: <432D47DF.30706@yahoo.com.au> (raw)
In-Reply-To: <200509160040.j8G0eFg06734@unix-os.sc.intel.com>
Chen, Kenneth W wrote:
> Take a look at http://kernel-perf.sourceforge.net/results.machine_id&.html
>
> First chart with volanomark benchmark. It took ~ 11% performance regression
> on 2.6.13-git9 and 2.6.14-rc1.
>
> It is not those two particular kernel version have the problem per se. It
> would've shown on 2.6.13-rc1 when default hz rate was switched to 250. Last
> week, I happened to audit the system and made the hz switch and the problem
> showed up.
>
> Hz\x1000 cpu idle is about 54%, the raw throughput is 74935 msgs/sec
> Hz%0 cpu idle is about 58%, the raw throughput is 67246 msgs/sec
>
> I think it has something to do with the scheduler load balance. While I'm
> looking into schedstat and etc. Posting here for everyone to pour over the
> issue.
>
> vmstat/readprofle/schedstat result with 1K hz and 250 hz attached.
>
Hi Ken,
Made any progress yet?
It looks like the problem is confined to ia64? Are the x86-64 machines
also running with HZ set to 250?
I would look at differences between SD_CPU_INIT for ia64 versus the
generic definition. cache_hot_time and cache_nice_tries by the looks,
both those could cause increased idle time.
Nick
--
SUSE Labs, Novell Inc.
Send instant messages to your online friends http://au.messenger.yahoo.com
next prev parent reply other threads:[~2005-09-18 10:56 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2005-09-16 0:40 Volanomark regress on ia64 Chen, Kenneth W
2005-09-18 10:56 ` Nick Piggin [this message]
2005-09-18 21:43 ` John Hawkes
2005-09-19 6:44 ` Chen, Kenneth W
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=432D47DF.30706@yahoo.com.au \
--to=nickpiggin@yahoo.com.au \
--cc=linux-ia64@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.