[time-nuts] Accurate timestamping on computers (previously: For mywhole life timezones have been weird)

David J Taylor david-taylor at blueyonder.co.uk
Sat Nov 3 11:31:18 UTC 2012


-----Original Message----- 
From: Sarah White
Sent: Saturday, November 03, 2012 9:49 AM

Thanks so much David...

Really. Thanks. I feel alot better now.

Regardless of documented issues on:
http://www.cl.cam.ac.uk/~mgk25/mswish/ut-rtc.html

(quote) The numerous past malfunctions of Microsoft operating systems
caused by keeping local time in the RTC and trying to cleverly perform
the RTC adjustment semi-automatically have been repeatedly the subject
of concerned public discussion: RISKS 16.54.1 RISKS 18.96.3 RISKS
19.11.16, RISKS 19.12.14 RISKS 19.43.13, RISKS 19.43.14, RISKS
22.34.3... (multiple links)

Not sure what timezone you're in...

... So I don't know which day your summer time ends this year. I'd love
to see the your loopstats file for as many of your windows boxes as
possible (with refclock, or without. Either is fine.) for the day of the
DST update this fall (and maybe any other loopstats data from when the
realtime clock got updated due to summer time / DST updates)

According to: http://www.satsignal.eu/mrtg/daily_ntp.html
(section: Hardware and OS configuration)

I'm assuming the relevant list is:

feenix, stamsund, bacchus, narvik, alta, molde, ystad, puffin, and any
other NT-5.x / NT 6.x based kernel (windows machines) I missed. Wow
that's a wonderfully diverse list :)

I actually thought about it a bit, and in hindsight I'm realizing that
internally, NTP uses a synthetic timebase anyway. Perhaps I was being
paranoid after all.

Thanks for the reply,
Sarah White

P.S. Your site has always had great documentation about NTP
configurations with a GPS-type reflock since I first saw it a couple
years ago. I've found it very useful.
================================================

Sarah,

There's really no issue over the hour change as NTP and Windows work in UTC 
internally, nevertheless, for your interest some loopstats are here:

  http://www.satsignal.eu/ntp/2012-10-28-loopstats.zip

I'm in UTC here, colloquially GMT/BST and we swap on the last Sunday of 
October.  My PCs all run with "wall clock" time displayed, and UTC 
internally (just the normal Windows default).  The RTC is only consulted at 
system boot time, so with systems running 24 x 7 there's no issue.  None of 
my systems multi-boot normally, just possibly the odd test PC may have Win-7 
and Win-8 installed.

I'm delighted that you find the site useful!

Cheers,
David
-- 
SatSignal Software - Quality software written to your requirements
Web: http://www.satsignal.eu
Email: david-taylor at blueyonder.co.uk 




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