Skip site navigation (1)Skip section navigation (2)
Date:      Mon, 08 Jan 2001 10:10:10 -0800
From:      Doug Barton <DougB@FreeBSD.org>
To:        Gordon Tetlow <gordont@bluemtn.net>
Cc:        Gerhard Sittig <Gerhard.Sittig@gmx.net>, freebsd-hackers@FreeBSD.org
Subject:   Re: OT: silence as an answer? (was: how to test out cron.c changes?)
Message-ID:  <3A5A0282.10EDAF5F@FreeBSD.org>
References:  <Pine.BSF.4.31.0101070454490.12363-100000@sdmail0.sd.bmarts.com>

next in thread | previous in thread | raw e-mail | index | archive | help
Gordon Tetlow wrote:
> 
> 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.

	Thank you. You just made my point. Did you actually read the last two
sentences of my paragraph?

> I think that cron is broken because it doesn't handle DST shift properly.

	And I think your definition of "properly" is broken. Cron doesn't "handle
DST" changes at all. It simply follows the system clock, which is 100%
understandable and reproducable behavior. I don't want to have to guess
what cron is going to do with any kind of time shift. 

> 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 agree with your premise, however I do not agree that this is a "good
solution." That is the point of contention here. 

Doug 
-- 
    "The most difficult thing in the world is to know how to do a thing and
     to watch someone else do it wrong without comment."
                     -- Theodore H. White

	Do YOU Yahoo!?


To Unsubscribe: send mail to majordomo@FreeBSD.org
with "unsubscribe freebsd-hackers" in the body of the message




Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?3A5A0282.10EDAF5F>