Re: [Wrapper-user] wrapperKillProcess()

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

Richard,

> Thank you for the explanation; the message:
> "JVM did not exit on request, terminated "
> refers to the fact that a previous request to stop the process
> failed and now it will be shutdown with a SIGKILL.
>
> We run load tests every night a multiple machine types. Every couple of
> days on one of our Linux boxes after running for a couple of hours
> we get the twin messages:
>
> JVM appears hung: Timed out waiting for signal from JVM.
> JVM did not exit on request, terminated
>
> one right after the other within milliseconds.
>
> The problem that arises after sending a SIGKILL to the process 
> controlled by the wrapper is that that primary process has spawned 
> secondary processes (not child processes) so that killing the primary 
> with at SIGKILL does not kill the secondary process - shutdown hooks 
> are registered but java will not execute them when a SIGKILL is received.
>
> In the file wrapper_unix.c in the function wrapperKillProcess() how 
> about first signaling with at SIGTERM, wait a while and then a SIGKILL.
> That way the primary process' shutdown hook might run?

The Wrapper does not send a SIGTERM to the JVM, but it does attempt to 
get the
JVM to shutdown cleanly.   The wrapperKillProcess function is only 
called when a
clean shutdown of the JVM has failed.  At that point, the JVM is most 
likely not
listening for SIGTERM or any other signals.  The SIGKILL is a last 
resort to get
rid of it.

Most likely your application is frozen at this point which is why it had 
not responded
to the exit requests.

If you are able to reproduce this so easily.  Could you try turning on 
debug output
with wrapper.debug=true and then letting that run until the JVM is 
restarted?  The
debug output will show exactly why the Wrapper decides that it is time 
to kill the
JVM process.   Most likely the JVM has stopped responding to ping requests.

Cheers,
Leif