Re: [Wrapper-user] JVM appears hung ??

[Leif M. <le...@ta...>]

Could you post your wrapper.conf file as well as your wrapper.log output
with wrapper.debug=true set? That debug output immediately before
those messages will tell me exactly why you are seeing them.

They are caused because the Wrapper has stopped receiving ping responses
from the JVM and has come to the conclusion that the JVM is frozen.
The Wrapper will restart the JVM after issuing this message.

If your JVM is not actually frozen then is being caused by the JVM not
getting any CPU for an extended period of time. The most common causes
of this are another high priority process eating all of the CPU, or the
machine being out of memory. Java does not like being swapped to disk.
It runs a couple of orders of magnitude slower when parts of its memory
space are being swapped to disk.

If you are using Wrapper 3.1.2, I would suggest setting
wrapper.use_system_time=false. In your wrapper.conf. This will enable the
the new tick based timer. It performs much better under heavy loads and
has been made the default for the next Wrapper release (3.2.0).

Cheers,
Leif

Cheers,
Leif

dp...@ro... wrote:

>We are getting the message, "JVM appears hung" at various times in the
>wrapper log files.
>
>What is issuing this message?  What is it actually checking to deceide to
>issue this message?  Is it the same program that then issues the restart?
>
>King
>
>  
>