Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755397AbZITS0K (ORCPT ); Sun, 20 Sep 2009 14:26:10 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755234AbZITS0J (ORCPT ); Sun, 20 Sep 2009 14:26:09 -0400 Received: from mail-yw0-f173.google.com ([209.85.211.173]:39874 "EHLO mail-yw0-f173.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755087AbZITS0I (ORCPT ); Sun, 20 Sep 2009 14:26:08 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=message-id:date:from:user-agent:mime-version:to:cc:subject :references:in-reply-to:content-type:content-transfer-encoding; b=CE3OZDEVCf7Mua3lrlLh1QFVHlpANNTHOoO+kOey5kiUP4kqPiVvCJlHZODsfNTlj0 OgiTwwZjktwckFbmu4HJmN6of3vAS6FiFvJ7HlRFP+TmJN36HYI9fkRxApV6NGMwKm/B edxpqECvOATZugTuL7F8psDFBKXK5vpNdoHKo= Message-ID: <4AB673C1.7020909@gmail.com> Date: Sun, 20 Sep 2009 12:26:09 -0600 From: Robert Hancock User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.1.1) Gecko/20090814 Fedora/3.0-2.6.b3.fc11 Thunderbird/3.0b3 MIME-Version: 1.0 To: Junhee Lee CC: linux-kernel@vger.kernel.org Subject: Re: microsecond event scheduling in an application References: <015f01ca3090$85e8a280$91b9e780$@kaist.ac.kr> In-Reply-To: <015f01ca3090$85e8a280$91b9e780$@kaist.ac.kr> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 966 Lines: 18 On 09/08/2009 08:27 AM, Junhee Lee wrote: > I am working on event scheduler which handles events in microsecond level. > Actual this program is a network emulator using simulation codes. > I'd like to expect that network emulator is working as simulation behaviors. > Thus high resolution timer interrupt is required. > But high resolution timer interrupt derived by high tick frequency (jiffies > clock) must effect the system performance. > Are there any comments or ways to support microsecond event scheduling > without performance degradation? Just increasing HZ will degrade performance, yes, but we have hrtimers now which should be able to use granularities smaller than one jiffy, so it shouldn't be needed.. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/