[ntp:questions] How do I prevent sudden system time jumps.

Miroslav Lichvar mlichvar at redhat.com
Thu Jul 14 10:24:50 UTC 2011

On Wed, Jul 13, 2011 at 10:51:46PM +0100, David Woolley wrote:
> Hal Murray wrote:
> >>OK.  I asked since a timewarp of 200ms is a bit surprising for real HW,
> >>but is something to be expected if you were running in a VM.
> >
> >It's easy to get a time-warp of 200 ms on a DSL link.  Just download
> >a huge file, say a CD.  The queuing delay on the input to the DSL
> >link turns into asymmetrical delays.  I've seen delays up to 3.5 seconds.
> >
> The huff and puff tinker optin can help mitigate this.

Please note that while the huffpuff option works very well with large
temporary asymmetric delays, it makes things worse with normal
delays as the offset will contain network jitter.

Miroslav Lichvar

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