From owner-freebsd-current Thu Mar 9 3: 6:13 2000 Delivered-To: freebsd-current@freebsd.org Received: from hda.hda.com (hda.bicnet.net [208.220.68.243]) by hub.freebsd.org (Postfix) with ESMTP id BC66C37B6D2 for ; Thu, 9 Mar 2000 03:06:07 -0800 (PST) (envelope-from dufault@hda.hda.com) Received: (from dufault@localhost) by hda.hda.com (8.9.3/8.9.3) id GAA65909; Thu, 9 Mar 2000 06:09:55 -0500 (EST) (envelope-from dufault) From: Peter Dufault Message-Id: <200003091109.GAA65909@hda.hda.com> Subject: Re: current lockups In-Reply-To: <00Mar9.114816est.115256@border.alcanet.com.au> from Peter Jeremy at "Mar 9, 2000 11:48:14 am" To: Peter Jeremy Date: Thu, 9 Mar 2000 06:09:55 -0500 (EST) Cc: current@freebsd.org X-Mailer: ELM [version 2.4ME+ PL61 (25)] MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-freebsd-current@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG > On 2000-Mar-09 10:05:21 +1100, Peter Dufault wrote: > >There's no difference between rtprio and P1003.1B scheduling other than > >the name. rtprio is the same as P1003.1B "SCHED_RR". > > I wasn't aware of that. > > >I'd like to remove the rtprio call from ntpd. I think we ought to do > >it now before 4.0 ships. > > Given there is a known a priority inversion bug related to realtime > (or idle) scheduling, it would seem wise not to use it in any system > utilities. The relevant patch would appear to be (untested): > > --- /usr/src/usr.sbin/ntp/config.h Tue Feb 1 13:56:05 2000 > +++ /tmp/config.h Thu Mar 9 11:46:11 2000 You have to do something in the "./configure" stuff. Hopefully someone in the know can suggest the "--with-no-foobar" option needed on the command line so I don't have to wade into it. Autoconfiguring POSIX realtime is a bad, bad idea because: 1. You don't know if it is available in all environments; 2. You don't know who is allowed to use it; 3. You don't know what the heck it does. It decidedly does not mean "run as fast as you can". Peter -- Peter Dufault (dufault@hda.com) Realtime development, Machine control, HD Associates, Inc. Fail-Safe systems, Agency approval To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-current" in the body of the message