Linux/390 does use the TOD clock. Under VM, CP provides a 'virtual TOD' for
each virtual machine that can be updated by that guest (a believe that it is
actually maintained as a delta to the hardware TOD). I believe that LPARs
provide a very similar mechanism.

> -----Original Message-----
> From: McKown, John [SMTP:[EMAIL PROTECTED]
> Sent: Monday, June 02, 2003 4:44 PM
> To:   [EMAIL PROTECTED]
> Subject:      Re: Time Sync
>
> Just an observation that may well be very stupid. Since Linux/390 can use
> NTP to sync time, then it must be that Linux/390 uses a "software" clock
> instead of the hardware clock (TOD clock). Is this true? If so, what
> happens
> if somebody down the line in the kernel maintainers decide that Linux
> should
> use the TOD clock instead of a "software" clock? Wouldn't that cause a
> problem? Or am I worrying about nothing. Unfortunately, I don't have the
> Linux/390 kernel source around, or I would look myself. I do know where to
> browse it on the Web, but only if I know the module that I want to view. I
> can't use grep to find where the clock lives.
>
>
> --
> John McKown
> Senior Systems Programmer
> UICI Insurance Center
> Applications & Solutions Team
> +1.817.255.3225
>
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>
> > -----Original Message-----
> > From: Richard Troth [mailto:[EMAIL PROTECTED]
> > Sent: Friday, May 30, 2003 4:48 PM
> > To: [EMAIL PROTECTED]
> > Subject: Re: Time Sync
> >
> >
> > Steve ...
> >
> > Linux/390 will synch time with NTP
> > just as effectively as Linux on a PC will.
> > VM does not benefit from this  (but is not harmed by it).
> > I have *not* found NTP to be a resource hog;  in fact,  it is
> > designed to be kind of low impact.   (Seems to sleep a lot
> > waiting for time to pass and then check again what time it is.)
> >
> > Hopefully you have an internal time reference.
> > If not,  you'll have to find one outside of your network.
> > (Probably okay,  but there's no telling how responsive they
> > will be since it is a courtesy of sorts.)   You're welcome to hit
> > my personal network  (at home).   Contact me off list for that addr.
> > (I'm not in the NTP biz.)
> >
> > -- R;
> >

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