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<== Date ==> <== Thread ==>

Subject: RE: Consequences of the leap-second
From: <[email protected]>
To: <[email protected]>, <[email protected]>
Date: Wed, 4 Jul 2012 09:17:11 +0000
From: [email protected] [mailto:[email protected]] On Behalf Of Andrew Johnson
> In case your site has this issue but maybe hasn't noticed yet:  
> There was a leap-second over the weekend, and it had all sorts
> of interesting consequences to Linux systems around the interwebs:
> http://www.pcmag.com/article2/0,2817,2406583,00.asp
> http://www.computerworld.com/s/article/9228720/Leap_second_bedevils_Web_systems_over_weekend?taxonomyId=122
> 
> It seems that all the RHEL6 systems at APS that were running any kind
> of a JVM have been pegging a CPU, and even Firefox is eating up 100%
> of a CPU on my box despite restarting the program.  An OS reboot
> apparently fixes the problem, but if you have any kind of OS support
> contract you might want to check with them first since they might
> have a less drastic fix available.

This is quite odd.  At Diamond we have a handful of RHEL6 boxes, but most of our workstations and servers are RHEL5, and we encountered very little trouble on Sunday.  I'm not of aware of any machine here that has shown problems other than the one event below.

All of our Libera EBPMs went into alarm state because they lost contact with their NTP server for about 40 minutes.  The timing is rather odd, here are the relevant logs from one machine:

Jun 30 23:59:59 (none) user.notice kernel: [5769351.673184] Clock: inserting leap second 23:59:60 UTC
Jul  1 00:12:22 (none) daemon.info ntpd[225]: no servers reachable
Jul  1 00:29:26 (none) daemon.info ntpd[225]: synchronized to 172.23.199.1, stratum 1
Jul  1 00:46:31 (none) daemon.notice ntpd[225]: time reset +0.997256 s
Jul  1 00:55:36 (none) daemon.info ntpd[225]: synchronized to 172.23.199.1, stratum 1

I'm perplexed, can't really understand what this is telling us.

I was telephoned about this (at 2:15am GMT, 1:15 am UTC, alas), but the problem solved itself as you can see from the logs above.

Let's abolish leap seconds, or maybe just use TAI for Linux timestamping ... difficult to see how, though, as it's a global choice.


References:
Consequences of the leap-second Andrew Johnson

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