JControl and JLaunch

[Former Member]

Please advise on following opinions whether they're right or not.

On windows platform,

1. Each Java instance has its own JControl process. (1:1)

2. For Java Central Instance, there are at least three JLaunch processes (Java dispatcher, Server, and SDM)

3. For Java Dialog Instance, there are at least two JLaunch processes (Java dispatcher, Server)

Thanks.

James

[Former Member · Accepted solution]

1. Each Java instance has its own JControl process. (1:1) - Yes.

2. For Java Central Instance, there are at least three JLaunch processes (Java dispatcher, Server, and SDM) - Yes, but don't forget the SCS. The SCS is the message server and enqueue, which is used by all application instances and CI.

3. For Java Dialog Instance, there are at least two JLaunch processes (Java dispatcher, Server) - Yes.

[Former Member]

Hi,

I hope below statements will help you to find answers.

u2022 JControl reads " instance. properties " and creates a list of the AS Java cluster elements to be started (4).

u2022 JControl starts a JLaunch process for each cluster element ( Central services , Java Central Instance, Otional Java instances ) (5).

This executes the following steps:

 The first argument of JLaunch is the PID of the parent process (JControl). JLaunch starts a thread, which ends the JLaunch process, if the parent process, JControl, fails.

 Creates JVM arguments and initializes hosting of the VM.

 Loads the VM into its own process, initializes the VM and starts the Java cluster element. This executes the following steps:

 Starts the u201Cofflineu201C configuration manager to read the properties for the Java Enterprise runtime from the database and to save them in various hash tables (6).

 Stops the u201Cofflineu201C configuration manager and starts the Java Enterprise runtime with the saved properties.

 Starts the service framework and the services.

[Former Member]

JControl processes

JControl starts, stops & monitors the processes of java instance.

JControl restarts terminated processes, ends hanging processes and sends a shutdown signal to Java instance.

JControl reads the description of Java instance from profile.

JControl start the JLaunch Java nodes (Dispatchers & Server)

JControl creates a Shared memory for internal adminu2019s of all

JLaunch

JLaunch processes

Receives commands from JControl (through named pipes)

JLaunch loads a JVM in a separate Process.

Rgrds

Deepu