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Re: [Ntp] CLOCK_TAI (was NTPv5: big picture)

Philip Prindeville <philipp@redfish-solutions.com> Mon, 04 January 2021 19:30 UTC

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From: Philip Prindeville <philipp@redfish-solutions.com>
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Date: Mon, 04 Jan 2021 12:30:23 -0700
Cc: Magnus Danielson <magnus@rubidium.se>, ntp@ietf.org
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To: Miroslav Lichvar <mlichvar@redhat.com>
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Subject: Re: [Ntp] CLOCK_TAI (was NTPv5: big picture)
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> On Jan 4, 2021, at 9:44 AM, Miroslav Lichvar <mlichvar@redhat.com> wrote:
> 
> On Mon, Jan 04, 2021 at 05:34:21PM +0100, Magnus Danielson wrote:
>>> It's been in the Linux kernel for years.
>>>       CLOCK_TAI (since Linux 3.10; Linux-specific)
>>>              A nonsettable system-wide clock derived from wall-clock
>>>              time but ignoring leap seconds.  This clock does not
>>>              experience discontinuities and backwards jumps caused by
>>>              NTP inserting leap seconds as CLOCK_REALTIME does.
>> Considering how long it's been in the kernel, I consider that for most
>> Linux systems, it can be used.
> 
> The Linux system TAI clock can be read by applications, but there is
> no support for timestamping of packets with this clock, i.e. it is
> currently not useful for NTP.
> 


That sounds like it’s really easily addressed…

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