[CentOS] leap second and Centos

Fri Mar 6 22:57:23 UTC 2015
Les Mikesell <lesmikesell at gmail.com>

On Fri, Mar 6, 2015 at 4:04 PM, Gordon Messmer <gordon.messmer at gmail.com> wrote:
> On 03/06/2015 01:41 PM, Les Mikesell wrote:
>>
>> I just want the package revisions for at least the kernel and tzdata*
>> files and anything else where previously-found bugs related to the
>> leap second have been fixed.
>
>
> https://access.redhat.com/articles/15145
> https://rhn.redhat.com/errata/RHSA-2013-0496.html

Helpful, but not exactly concise...  And I don't understand the
concept of /usr/share/zoneinfo/right/*. Are those supposed to print
the right time if your clock is left wrong?

> Contrary to your previous assertion, in 2012, it was not the kernel that
> consumed CPU cycles.  That problem was seen in user space.

But it is just as much the kernel's fault if it returns from
nanosleep()/usleep() instantly without counting any time down so you
spin in user space as if stayed in the kernel.  Nothing in user space
could have fixed it.

> The problem was
> fixed by changing the kernel's implementation of leap second handling, but
> the reason that you are being told that testing your applications is the
> only way to verify that there is not a problem is that these problems aren't
> confined to the kernel and tzdata packages.

Unknown problems can happen anywhere/any time.

-- 
   Les Mikesell
     lesmikesell at gmail.com