From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S270760AbTG0LfV (ORCPT ); Sun, 27 Jul 2003 07:35:21 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S270762AbTG0LfU (ORCPT ); Sun, 27 Jul 2003 07:35:20 -0400 Received: from c210-49-248-224.thoms1.vic.optusnet.com.au ([210.49.248.224]:19351 "EHLO mail.kolivas.org") by vger.kernel.org with ESMTP id S270760AbTG0LfM (ORCPT ); Sun, 27 Jul 2003 07:35:12 -0400 From: Con Kolivas To: Ingo Molnar , Willy Tarreau Subject: Re: Ingo Molnar and Con Kolivas 2.6 scheduler patches Date: Sun, 27 Jul 2003 21:54:31 +1000 User-Agent: KMail/1.5.2 Cc: Andrew Morton , Daniel Phillips , , , References: In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200307272154.31689.kernel@kolivas.org> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Sun, 27 Jul 2003 19:12, Ingo Molnar wrote: > On Sun, 27 Jul 2003, Willy Tarreau wrote: > > just a thought : have you tried to set the timer to 100Hz instead of > > 1kHz to compare with 2.4 ? It might make a difference too. > > especially for X, a HZ of 1000 has caused performance problems before - > short-timeout select()s were looping 10 times faster, which can be > noticeable. No doubt X was a bit smoother at 100Hz in 2.5, but not remarkably so. In 2.4 O(1) there was a slight X flutter (jerkiness) at 1000Hz not evident at 100Hz, but very consistent in the frequency/duration of that jerkiness. The difference is in 2.5, when X is not smooth it's almost like there's jitter in the jerkiness. Con