From owner-freebsd-questions@FreeBSD.ORG Sat Jul 29 19:46:58 2006 Return-Path: X-Original-To: freebsd-questions@freebsd.org Delivered-To: freebsd-questions@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 1AC6C16A4E6 for ; Sat, 29 Jul 2006 19:46:58 +0000 (UTC) (envelope-from cswiger@mac.com) Received: from pi.codefab.com (pi.codefab.com [199.103.21.227]) by mx1.FreeBSD.org (Postfix) with ESMTP id 3448043D53 for ; Sat, 29 Jul 2006 19:46:50 +0000 (GMT) (envelope-from cswiger@mac.com) Received: from localhost (localhost [127.0.0.1]) by pi.codefab.com (Postfix) with ESMTP id 6E8B55CE0; Sat, 29 Jul 2006 15:46:49 -0400 (EDT) X-Virus-Scanned: amavisd-new at codefab.com Received: from pi.codefab.com ([127.0.0.1]) by localhost (pi.codefab.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id i7S-ENe8GJ7t; Sat, 29 Jul 2006 15:46:48 -0400 (EDT) Received: from [192.168.1.251] (pool-68-161-117-245.ny325.east.verizon.net [68.161.117.245]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by pi.codefab.com (Postfix) with ESMTP id 2FDFF5C33; Sat, 29 Jul 2006 15:46:48 -0400 (EDT) Message-ID: <44CBBB24.6020107@mac.com> Date: Sat, 29 Jul 2006 15:46:44 -0400 From: Chuck Swiger User-Agent: Thunderbird 1.5.0.5 (Windows/20060719) MIME-Version: 1.0 To: David Godsey References: <1659.71.213.169.51.1154123874.squirrel@godseyfamily.com> <2555.71.213.169.51.1154193278.squirrel@godseyfamily.com> In-Reply-To: <2555.71.213.169.51.1154193278.squirrel@godseyfamily.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: freebsd-questions@freebsd.org Subject: Re: Real Time scheduling X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 29 Jul 2006 19:46:58 -0000 David Godsey wrote: > If this is not the list to ask this question, can someone kindly direct me > to the right list. I've been out of the FreeBSD loop for a while and just > now getting back (my vocation requires that I use linux at work). You might try asking on freebsd-realtime@ instead, although this list is a fine place to ask questions in general. >> I have seen a blurb on realtime scheduling with FreeBSD, however there >> weren't many details on it. I'm looking for things like: >> >> 1) Is it similar to an RTOS with preemption, or it is round robin? >> 2) What is the jitter? >> 3) how to use that feature. I don't believe the main FreeBSD project is doing much with realtime directly, although some of the variants like Nano/PicoBSD had people doing RTOS using very pared-down, minimalistic, systems. And a lot of the work in 5.x and 6.x drivers to remove dependencies on the Giant kernel lock will help realtime as well as SMP situations. You might want to be patient and wait a few days to see whether you get better, more specific responses. -- -Chuck