[tz] New Yorker article on David Mills and NTP

[John Haxby]

> On 7 Oct 2022, at 00:24, Steffen Nurpmeso via tz <tz at iana.org> wrote:
> 
> But only to throw in that for most systems which are not
> always-on, and even for some which are, this is rather
> hypothetic since hardware clocks that i know drift (and
> Linux hwclock(8) documents "The Hardware Clock is usually not
> very accurate. However, much of its inaccuracy is completely
> predictable - it gains or loses the same amount of time every
> day. This is called systematic drift.")
> 

The clock described by hwclock(8) is not the system clock, it's the RTC for Linux/Unix it's only used to set the initial system time on boot.  The system clock is the one that has a predictable drift (eg 7ppm on this machine here).

The RTC is basically a 2¢ chip and every bit as accurate as you'd expect; my wind-up watch is more accurate.

jch
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