Pivotal Knowledge Base

Follow

Implication of Second Leap 2015 on Pivotal tc Server and Pivotal Web Server

Second Leap 2015 has no impact for both Pivotal tc Server and Pivotal Web Server. For more details on Second Leap [1]

Pivotal Web Server

No impact. Time is used throughout httpd to measure progress in terms of deltas between the beginning and end of a request, and similar.

Requests in-flight during the LeapSecond may exhibit negative processing time durations, in some cases these may be represented by third party modules in an unsigned form. This may confuse log parsing with some user-specified complex log format statements, but causes no errors in data collection.

There are no operational errors expected. The httpd server regularly observes small time adjustments during the normal course of operation, where the system clock is re-synchronized to the reference clock. This has been an anticipated behavior since the software was initially created in the mid '90s.

Pivotal tc Server / Apache Tomcat

There are no known issues with leap seconds and tc Server (or Apache Tomcat).

The 2012 leap second issues, even the Java ones, were down to a Linux kernel bug[2]. Provided that any machines running tc Server on Linux are fully patched with respect to OS updates you should not see a recurrence of this issue.

You may wish to monitor CPU usage when the leap second is added and, should any servers show a CPU spike, apply one of the known workarounds such as [3]. Alternatively, the you can use an NTP server that, rather than adding a leap second in one go, adds a few milliseconds here, a few milliseconds there until the second has been added.

[1] https://support.pivotal.io/hc/en-us/articles/204702147-Leap-second-impact-on-Linux-systems
[2] https://www.shell-tips.com/2015/01/05/impact-of-positive-leap-second-introduced-in-june/
[3] http://blog.wpkg.org/2012/07/01/java-leap-second-bug-30-june-1-july-2012-fix/

Comments

Powered by Zendesk