From owner-freebsd-hackers Wed Mar 29 05:37:12 1995 Return-Path: hackers-owner Received: (from majordom@localhost) by freefall.cdrom.com (8.6.10/8.6.6) id FAA17861 for hackers-outgoing; Wed, 29 Mar 1995 05:37:12 -0800 Received: from UUCP-GW.CC.UH.EDU (root@UUCP-GW.CC.UH.EDU [129.7.1.11]) by freefall.cdrom.com (8.6.10/8.6.6) with SMTP id FAA17855 for ; Wed, 29 Mar 1995 05:37:10 -0800 Received: from Taronga.COM by UUCP-GW.CC.UH.EDU with UUCP id AA21532 (5.67a/IDA-1.5); Wed, 29 Mar 1995 07:31:32 -0600 Received: by bonkers.taronga.com (smail2.5p) id AA17995; 29 Mar 95 07:30:50 CST (Wed) Received: (from peter@localhost) by bonkers.taronga.com (8.6.11/8.6.6) id HAA17992; Wed, 29 Mar 1995 07:30:50 -0600 From: Peter da Silva Message-Id: <199503291330.HAA17992@bonkers.taronga.com> Subject: Re: FreeBSD support for realtime systems To: fernando@cea.Berkeley.EDU (Fernando Astorga) Date: Wed, 29 Mar 1995 07:30:49 -0600 (CST) Cc: hackers@FreeBSD.org In-Reply-To: <199503291239.EAA04745@halfmoon.cea.berkeley.edu> from "Fernando Astorga" at Mar 29, 95 04:39:49 am X-Mailer: ELM [version 2.4 PL23] Content-Type: text Content-Length: 648 Sender: hackers-owner@FreeBSD.org Precedence: bulk We are currently running a "soft" real time (SCADA) system on UNIX with realtime extensions. I haven't tried running real time on traditional UNIX. My suggestion would be to investigate Andy Valencia's "vsta" microkernel first. It should have better real-time characteristics than FreeBSD. You may have to write custom device drivers to packetise and timestamp events received from lab devices, and schedule responses, if you need precise control. I cerytainly would in a production environment. For an educational setting, though, a little slop might not be a serious problem. It all depends on how tight your real-time requirements really are.