From owner-freebsd-small Wed Jul 5 13:34:53 2000 Delivered-To: freebsd-small@freebsd.org Received: from rover.village.org (rover.village.org [204.144.255.49]) by hub.freebsd.org (Postfix) with ESMTP id D17B937BE9C for ; Wed, 5 Jul 2000 13:34:47 -0700 (PDT) (envelope-from imp@harmony.village.org) Received: from harmony.village.org (harmony.village.org [10.0.0.6]) by rover.village.org (8.9.3/8.9.3) with ESMTP id OAA17662; Wed, 5 Jul 2000 14:34:45 -0600 (MDT) (envelope-from imp@harmony.village.org) Received: from harmony.village.org (localhost.village.org [127.0.0.1]) by harmony.village.org (8.9.3/8.8.3) with ESMTP id OAA43088; Wed, 5 Jul 2000 14:34:25 -0600 (MDT) Message-Id: <200007052034.OAA43088@harmony.village.org> To: Brandon Fosdick Subject: Re: Real Time picoBSD? Cc: small@FreeBSD.ORG In-reply-to: Your message of "Wed, 05 Jul 2000 15:47:37 EDT." <396390D9.A2E8E9CC@glue.umd.edu> References: <396390D9.A2E8E9CC@glue.umd.edu> Date: Wed, 05 Jul 2000 14:34:25 -0600 From: Warner Losh Sender: owner-freebsd-small@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG In message <396390D9.A2E8E9CC@glue.umd.edu> Brandon Fosdick writes: : What kind of real time performance can one get with picoBSD? I've seen : the real time extensions for FreeBSD, but I haven't found anyway to keep : the kernel from preempting my RT processes. Are the RT extensions : available in picoBSD? Can I set the kernel priority? At best, you can arrange fro pseudo real time stuff. There's the RTPRIO that you can run processes at, but this doesn't guarantee any sort of response time. In most of the systems I've designed, I've put the really time critical parts into the driver that talks to the hardware. So far this has worked, but I do know there are instances where it wouldn't. Warner To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-small" in the body of the message