Re: Scary bugs

[Ryan Murray <rmurray@cyberhqz.com>]

On Sat, Jan 29, 2000 at 11:01:04AM +0100, Thierry Laronde wrote:

> > > I don't think that's the problem.  Setting the hardware clock again to
> > > the system time isn't the problem.  The problem is, as you mention:
> > > 
> > > > When the system is going down for halt or reboot, hwclock is set to the
> > > > value of the system clock and this *modifies /etc/adjtime*.
> > > 
> > > /etc/adjtime.  There is no reason to have hwclock trying to calculate
> > > drift, as either NTP will be used (which is far more accurate), or the
> > > system will be rebooting between Windows and Linux frequently.
> > > 
> > > A new user will expect their time to follow them between OS', so I think
> > > instead, the support for /etc/adjtime should be removed (comment out the
> > > --adjust line in hwclock).  That's what I'm doing and don't have these
> > > problems.
> > 
> > This has nothing to do with making the time follow them between OS's --
> > what /etc/adjtime does is keep track of the drift, and adjusting the
> > hardware clock to counteract it.  So it's supposed to make your clock
> > more accurate in both linux and windows.
> 
> clock when the system is boot or reboot. Because the hardware clock isn't
> very accurate (but predictable), /etc/adjtime allows to adjust the
> hardware clock at boot-time.

As has been pointed out, we don't know that the user is ONLY using
hwclock to adjust their clock.  Most new-to-Linux users won't know that
hwclock is where all changes are supposed to happen.

> By the way, the "correction" made to the init script (commenting out
> the initial correction of the drift) is a mistake. Please see my
> other mail.

If the clock is set by something other than hwclock, or the system is
off for a few days, the clock warps because of this "correction".  I'd
rather see new users having their clock drift slightly than warping
several hours because of this, which is why commenting out the
adjustment, and ignoring this feature of hwclock seems to be the best
thing to do, for now.

I'd also like to see hwclock in a seperate package so that ntp and
similar can conflict with it.

Also, the new-to-Linux users probably don't know about the two clocks
(system vs. hardware) that Linux uses, and will assume the one they see
in their gnome panel, X applications, and "date" is the only clock their
is.

-- 
Ryan Murray, (rmurray@cyberhqz.com, rmurray@stormix.com)
Programmer, Stormix Technologies Inc.
The opinions expressed here are my own.