public inbox for linux-kernel@vger.kernel.org
 help / color / mirror / Atom feed
From: Vincent Pelletier <vincent.plr@wanadoo.fr>
To: linux-kernel@vger.kernel.org
Cc: mingo@elte.hu
Subject: Re: [PATCH] sched.c: Be a bit more conservative in SMP
Date: Thu, 7 Sep 2006 01:30:53 +0200	[thread overview]
Message-ID: <200609070130.53995.vincent.plr@wanadoo.fr> (raw)
In-Reply-To: <200609031910.57259.vincent.plr@wanadoo.fr>

I found one maybe-drawback to this change :
When runing n+1 process (n = number of cpu), one takes one cpu, the other 2 
share another cpu. And, because of this patch, all processes stay in their 
own cpu, so one always has 100% of cpu power, the 2 others get 50% each.
In current implementation, one of the 2 processes from the same cpu would 
migrate to the other cpu, and so on, somehow sharing cpu time among them.
Is it a feature or a side effect of current implementation ?

I'll do some tests soon to see which version gives better performance at a 
higher level than just process migration cost - if different at all.
-- 
Vincent Pelletier

  reply	other threads:[~2006-09-06 23:30 UTC|newest]

Thread overview: 11+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2006-09-03 13:41 [PATCH] sched.c: Be a bit more conservative in SMP Vincent Pelletier
2006-09-03 17:10 ` Vincent Pelletier
2006-09-06 23:30   ` Vincent Pelletier [this message]
2006-09-19 14:06     ` Ludovic Drolez
2006-09-19 17:50       ` Antonio Vargas
2006-09-20  7:42         ` Ludovic Drolez
2006-09-20 16:26           ` Poor scheduling when not loaded at 100% (Was: [PATCH] sched.c: Be a bit more conservative in SMP) Ludovic Drolez
2006-09-21 18:36           ` [PATCH] sched.c: Be a bit more conservative in SMP Vincent Pelletier
2006-09-22  7:24             ` Ludovic Drolez
2006-09-22 12:31               ` Antonio Vargas
2006-09-19 13:39 ` Ludovic

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=200609070130.53995.vincent.plr@wanadoo.fr \
    --to=vincent.plr@wanadoo.fr \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mingo@elte.hu \
    /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