public inbox for linux-kernel@vger.kernel.org
 help / color / mirror / Atom feed
From: William Lee Irwin III <wli@holomorphy.com>
To: Peter Williams <pwil3058@bigpond.net.au>
Cc: Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
	Michal Kaczmarski <fallow@op.pl>,
	Shane Shrybman <shrybman@aei.ca>
Subject: Re: [PATCH] V-3.0 Single Priority Array O(1) CPU Scheduler Evaluation
Date: Wed, 4 Aug 2004 19:00:41 -0700	[thread overview]
Message-ID: <20040805020041.GQ2334@holomorphy.com> (raw)
In-Reply-To: <4111882B.9090504@bigpond.net.au>

William Lee Irwin III wrote:
>> Software constructs are less of a concern. This also presumes that
>> taking timer interrupts when cpu-intensive workloads voluntarily
>> yield often enough is necessary or desirable.

On Thu, Aug 05, 2004 at 11:06:51AM +1000, Peter Williams wrote:
> Voluntary yielding can't be relied upon.  Writing a program that never 
> gives up the CPU voluntarily is trivial.  Some have been known to do it 
> without even trying :-)

No reliance is implied. In such a scenario, the timers for timeslice
expiry are always cancelled because userspace voluntarily yields first,
so no timer interrupts are delivered. Should userspace fail to do so,
timer interrupts programmed for timeslice expiry would not be cancelled.


-- wli

  reply	other threads:[~2004-08-05  2:00 UTC|newest]

Thread overview: 22+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2004-08-02  6:31 [PATCH] V-3.0 Single Priority Array O(1) CPU Scheduler Evaluation Peter Williams
2004-08-02 13:42 ` William Lee Irwin III
2004-08-03  0:33   ` Peter Williams
2004-08-03  2:03     ` William Lee Irwin III
2004-08-03  3:39       ` Peter Williams
2004-08-03 10:49         ` William Lee Irwin III
2004-08-04  0:37           ` Peter Williams
2004-08-04  0:50             ` William Lee Irwin III
2004-08-04  1:36               ` Peter Williams
2004-08-04  1:51                 ` William Lee Irwin III
2004-08-04  2:40                   ` Peter Williams
2004-08-04  7:05                     ` Ingo Molnar
2004-08-04  7:44                     ` William Lee Irwin III
2004-08-05  1:06                       ` Peter Williams
2004-08-05  2:00                         ` William Lee Irwin III [this message]
2004-08-05  2:12                           ` Peter Williams
     [not found] <2oEEn-197-9@gated-at.bofh.it>
2004-08-02 13:27 ` Andi Kleen
2004-08-03  0:27   ` Peter Williams
2004-08-03  3:53     ` Andrew Morton
2004-08-03  4:38       ` Peter Williams
2004-08-03  6:51       ` Andi Kleen
  -- strict thread matches above, loose matches on Subject: below --
2004-08-07  1:44 Peter Williams

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=20040805020041.GQ2334@holomorphy.com \
    --to=wli@holomorphy.com \
    --cc=fallow@op.pl \
    --cc=linux-kernel@vger.kernel.org \
    --cc=pwil3058@bigpond.net.au \
    --cc=shrybman@aei.ca \
    /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