From owner-freebsd-current@FreeBSD.ORG Fri Aug 12 03:12:06 2005 Return-Path: X-Original-To: freebsd-current@freebsd.org Delivered-To: freebsd-current@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 6C45516A41F for ; Fri, 12 Aug 2005 03:12:06 +0000 (GMT) (envelope-from jmg@hydrogen.funkthat.com) Received: from hydrogen.funkthat.com (gate.funkthat.com [69.17.45.168]) by mx1.FreeBSD.org (Postfix) with ESMTP id F105043D45; Fri, 12 Aug 2005 03:12:05 +0000 (GMT) (envelope-from jmg@hydrogen.funkthat.com) Received: from hydrogen.funkthat.com (localhost.funkthat.com [127.0.0.1]) by hydrogen.funkthat.com (8.13.3/8.13.3) with ESMTP id j7C3C5Ug071504; Thu, 11 Aug 2005 20:12:05 -0700 (PDT) (envelope-from jmg@hydrogen.funkthat.com) Received: (from jmg@localhost) by hydrogen.funkthat.com (8.13.3/8.13.3/Submit) id j7C3C5j5071503; Thu, 11 Aug 2005 20:12:05 -0700 (PDT) (envelope-from jmg) Date: Thu, 11 Aug 2005 20:12:04 -0700 From: John-Mark Gurney To: Bsderss Message-ID: <20050812031204.GL62369@funkthat.com> Mail-Followup-To: Bsderss , freebsd-current@freebsd.org, freebsd-question@freebsd.org References: <20050810081227.8074.qmail@web54401.mail.yahoo.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20050810081227.8074.qmail@web54401.mail.yahoo.com> User-Agent: Mutt/1.4.2.1i X-Operating-System: FreeBSD 5.4-RELEASE-p1 i386 X-PGP-Fingerprint: B7 EC EF F8 AE ED A7 31 96 7A 22 B3 D8 56 36 F4 X-Files: The truth is out there X-URL: http://resnet.uoregon.edu/~gurney_j/ X-Resume: http://resnet.uoregon.edu/~gurney_j/resume.html Cc: freebsd-question@freebsd.org, freebsd-current@freebsd.org Subject: Re: kqueue/kevent in real-time OS? X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list Reply-To: John-Mark Gurney List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 12 Aug 2005 03:12:06 -0000 Bsderss wrote this message on Wed, Aug 10, 2005 at 01:12 -0700: > Can anyone please tell me is kqueue/kevent model in > FreeBSD 5.x a real-time event model? I'm not sure what you mean by real-time event model, but most likely, no it is not.. It requires a process/thread to be waiting in kevent, and there are no guarantees about the time from when the event that triggers the wakeup and the time that your thread will run.. With some combination of rtprio, the thread priority can be raised... There is no other method to get notification of kqueue waking up, than kevent.. -- John-Mark Gurney Voice: +1 415 225 5579 "All that I will do, has been done, All that I have, has not."