Re: [Wrapper-user] Limit on started JVMs under NT Service

[Todd W. <to...@sc...>]

This may or may not help, but we encountered an issue related to
spawning a separate VM that may provide insight.

When our app starts up it spawns a separate Java process for its
database (resulting in two processes).  We spawn the second process
using the Ant (http://ant.apache.org/) API (which I'd recommend instead
of using Runtime, by the way).  The problem we encountered was that when
the user that spawned our application logged out of Windows it killed
the database (second) process; however, the original process stayed
alive.  After experimenting for a bit we finally threw our hands in the
air and resolved it by launching the database within the same process as
the main app, so that we only had one process.

If anyone has insight into the issue I'd love to hear it.  Otherwise,
our workaround is working fine.

Kind regards,

Todd Wilson


On Wed, 1 Mar 2006 17:45:59 +0100, "Christian Cardinale"
<car...@ap...> said:
> Hi everyone,
> 
> I tried to install several NT services using the Java Service Wrapper.
> Each of these services executes a JAVA program, spanning a couple of JVMs
> (using basically the exec method from Runtime class).
> 
> Let say:
> Service NT_SVC1 : A java application, starting 8 children JVMs
> Service NT_SVC2 : A java application, starting 5 children JVMs
> Service NT_SVC3 : A java application, starting 5 children JVMs
> 
> 
> The problem I encounter is that the system refuses to start more than 16
> JVMs. The 17th is killed as soon as it has been started
> No matter the Wrapper started first, I'm always getting 16 JVM started.
> 
> In my example : starting NT_SVC1, then NT_SVC2, then NT_SVC3, only 3 JVMs
> from NT_SVC3 are started.
> If I kill 1 JVM from NT_SVC1 and I restart NT_SVC3, I notice 1 more JVM
> is
> started from NT_SVC3.
> 
> Is there any limitation in Java Service Wrapper, or in NT services that I
> reached ?
> 
> Any help would be appreciated.
> 
> Best regards,
> Christian Cardinale
>