public inbox for linux-kernel@vger.kernel.org
 help / color / mirror / Atom feed
From: "Chris Friesen" <cfriesen@nortel.com>
To: Con Kolivas <kernel@kolivas.org>
Cc: Robert Love <rml@novell.com>, Ingo Molnar <mingo@elte.hu>,
	Linus Torvalds <torvalds@osdl.org>,
	Linux kernel <linux-kernel@vger.kernel.org>,
	Andrew Morton <akpm@osdl.org>
Subject: Re: resend: KERNEL BUG: nice level should not affect SCHED_RR timeslice
Date: Mon, 12 Mar 2007 09:18:15 -0600	[thread overview]
Message-ID: <45F56F37.6090407@nortel.com> (raw)
In-Reply-To: <200703122027.17219.kernel@kolivas.org>

Con Kolivas wrote:

> Indeed we do change timeslice with nice on rt_tasks in mainline at the moment. 
> Truth is most rt programming couldn't care less about timeslices, but your 
> point about it deviating from the standard is valid. RSDL does not change 
> timeslice with nice on SCHED_RR tasks so it's sort of getting addressed by 
> proxy.

Unfortunately we have some vendor-supplied software that does care about 
timeslices.  It's a crazy thing with multiple SCHED_RR kernel threads 
that don't really self-manage very well.  They're spawned by a 
SCHED_OTHER task and inherit its nice level.

We modified the startup for the spawning task to run it at a lower nice 
level and were fairly surprised when the latency of message handling 
went way up.

Chris

  reply	other threads:[~2007-03-12 15:18 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2007-03-07 23:19 resend: KERNEL BUG: nice level should not affect SCHED_RR timeslice Chris Friesen
2007-03-12  9:27 ` Con Kolivas
2007-03-12 15:18   ` Chris Friesen [this message]
  -- strict thread matches above, loose matches on Subject: below --
2007-03-06 15:43 Chris Friesen

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=45F56F37.6090407@nortel.com \
    --to=cfriesen@nortel.com \
    --cc=akpm@osdl.org \
    --cc=kernel@kolivas.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mingo@elte.hu \
    --cc=rml@novell.com \
    --cc=torvalds@osdl.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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox