On Sun, 1 Jul 2012, Peter van Hooft wrote:

> Hi,
>
> On 6.2 (2.6.32-220.23.1.el6.x86_64) I noticed that qpidd started to use an
> enormous amount of cpu time. It is probably related to the last leap second.
> Doing an strace I saw it doing futex() calls in a furious rate.
> After doing the
> export LANG=C
> date; date `date +"%m%d%H%M%C%y.%S"`; date
> trick and restarting qpidd, the problem was gone.

Caused by a kernel bug in > 2.6.26 (apparently) < 3.4.something.  See:

   http://serverfault.com/questions/403732/anyone-else-experiencing-high-rates-of-linux-server-crashes-during-a-leap-second

which in turn points at:

   https://access.redhat.com/knowledge/solutions/154713
   https://access.redhat.com/knowledge/articles/15145

for the RHEL6 info...  The solutions stuff seems to require a subscription 
to view in full.

Note that there seem to have been two bugs one may have caused a hard 
crash at any time on the day leading up to the leap-second, and the other 
causes excessive CPU usage after the leap-second has been applied. 
Machines with higher loads were more likely to suffer the hard crash.

The bug all distros with the bad ranges of kernels, so e.g. el5/sl5 seems 
not to have been affected though el6/sl6 were.

  -- Jon