From owner-freebsd-hackers Sun Jan 7 5: 7:13 2001 Delivered-To: freebsd-hackers@freebsd.org Received: from sdmail0.sd.bmarts.com (sdmail0.sd.bmarts.com [192.215.234.86]) by hub.freebsd.org (Postfix) with SMTP id 445F237B402 for ; Sun, 7 Jan 2001 05:06:55 -0800 (PST) Received: (qmail 23734 invoked by uid 1078); 7 Jan 2001 13:07:06 -0000 Received: from localhost (sendmail-bs@127.0.0.1) by localhost with SMTP; 7 Jan 2001 13:07:06 -0000 Date: Sun, 7 Jan 2001 05:07:06 -0800 (PST) From: Gordon Tetlow X-X-Sender: To: Doug Barton Cc: Gerhard Sittig , Subject: Re: OT: silence as an answer? (was: how to test out cron.c changes?) In-Reply-To: <3A564E90.A49E1BE1@gorean.org> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG Hello there! On Fri, 5 Jan 2001, Doug Barton wrote: > Gerhard Sittig wrote: [snip] > > Consider the following. We are in the spring and DST is "springing > forward" at 2am. We have a job scheduled at 2:15 that takes one hour to > run. There is another job scheduled at 3:20 that ABSOLUTELY POSITIVELY > cannot run unless the first job finishes. Aside from the fact that this > is bad design, how should cron handle this situation? You can (and > probably should) respond that this is not cron's responsibility, and > come up with all kinds of ways to ameliorate this situation. My response > will then be that if you can "fix" this situation without "fixing" cron, > then cron doesn't really need to be "fixed." I think this is a really horrible example. It is impossible for FreeBSD to expect to catch bad design on a local administrator's part. The admin should implement some sort of semaphore (a file in /tmp) or just append the dependent job to the first job. We can't insulate stupidity, at least we shouldn't, otherwise FreeBSD is going to start looking more like Windows. I think that cron is broken because it doesn't handle DST shift properly. Just my opinion though, and we seem to get plenty of those around here =) > With very little imagination you could easily come up with other > situations where your proposed changes will cause more harm than good. > On the other hand, the "damage" that cron is doing in these situations > can easily be repaired by proper system design. Therefore your changes > should not be incorporated. I'm rather confused by the paragraph there. It almost seems like your second sentence is contradicting the other two. Can you clarify "these" in the second paragraph? Of course, I have a horrible head cold that's keeping me from sleeping, so if it's perfectly obvious to everyone else, I'll be quiet and go back to bed. OpenBSD seems to get by with these changes just fine. I have a lot of respect for them and I think if they come up with a good solution to the DST problem, we should seriously consider it. I'm having a hard time coming up with good examples of harm, but then again, this head cold is somewhat impairing my faculties. Cheers, -gordon To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message