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Re: [Ntp] Antwort: Re: The bump, or why NTP v5 must specify impulse response

Daniel Franke <dfoxfranke@gmail.com> Fri, 17 April 2020 16:39 UTC

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From: Daniel Franke <dfoxfranke@gmail.com>
Date: Fri, 17 Apr 2020 12:39:11 -0400
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To: Warner Losh <imp@bsdimp.com>
Cc: kristof.teichel@ptb.de, NTP WG <ntp@ietf.org>
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Subject: Re: [Ntp] Antwort: Re: The bump, or why NTP v5 must specify impulse response
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On Fri, Apr 17, 2020 at 12:22 PM Warner Losh <imp@bsdimp.com> wrote:
> Well, the OS provides an 'abstract' counter, but only kinda. Usually it integrates the past to some point in time after the last counter wrap and then uses the delta from that point to the current counter to compute the time. The OS may have a hard time providing a pure counter to NTP, and it should be designed such that it may only get the low order bits from the counter and an OS timestamp...

On Linux, at least, there's CLOCK_MONOTONIC_RAW which is the kind of
thing I have in mind.

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