Re: [OT] Major Clock Drift

From: Pavel Machek (pavel@suse.cz)
Date: Sun Feb 11 2001 - 06:06:14 EST


Hi!

> > > > >I've discovered that heavy use of vesafb can be a major source of clock
> > > > >drift on my system, especially if I don't specify "ypan" or "ywrap". On my
> > > >
> > > > This is extremely interesting. What version of ntp are you using?
> > >
> > > Is vesafb one of the drivers which blocks interrupts for (many) tens
> > > of milliseconds?
> >
> > Vesafb is happy to block interrupts for half a second.
>
> And has this been observed to cause clock drift?

YEs. I've seen time running 3 times slower. Just do cat /etc/termcap
with loaded PCI bus. Yesterday I lost 20 minutes during 2 hours -- I
have been using USB (load PCI) and framebuffer.
                                                                Pavel

-- 
The best software in life is free (not shareware)!		Pavel
GCM d? s-: !g p?:+ au- a--@ w+ v- C++@ UL+++ L++ N++ E++ W--- M- Y- R+
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This archive was generated by hypermail 2b29 : Thu Feb 15 2001 - 21:00:16 EST