Configuring and Managing Java Virtual Machines 10-15
2.
Select the JVM controller that you want to start. A JVM that is not running is indicated by a red, down arrow.
3. Click Start.
When the JVM controller has started, a green, up arrow Figure 10–5
is displayed in the Status.
To restart a running JVM controller: 1.
From the Forms menu, select JVM Controllers. The JVM Controllers page is displayed.
2.
Select the JVM controller to be restarted.
3. Click Restart.
4. Click Yes on the Confirmation dialog.
The JVM Controller page reappears.
When the JVM controller has restarted, a green, up arrow is displayed in the Status.
To stop a JVM Controller 1.
From the Forms menu, select JVM Controllers. The JVM Controllers page is displayed.
2.
Select the running JVM controller that you want to stop, indicated by a green, up arrow.
3. Click Stop.
4. Click Yes on the Confirmation dialog.
When the JVM controller has been stopped, a red, down arrow Figure 10–5
is displayed in the Status.
To view additional details of a JVM Controller 1.
From the Forms menu, select JVM Controllers. The JVM Controllers page is displayed.
2.
Click the plus symbol next to the JVM controller. The row is expanded to display additional details
Figure 10–5 of the JVM controller.
10.8.6 Forms Configuration File Settings
This section describes the JVM pooling parameters that are used in the Forms configuration file formsweb.cfg to enable or disable use of JVM controller for
applications. The parameter names are not case-sensitive. You can use Fusion Middleware Control to administer the Forms configuration file.
Table 10–5, Oracle Forms JVM Controller Startup Parameters describes the startup
options that you specify in the formsweb.cfg file. For more information on modifying the parameters in formsweb.cfg, see
Section 4.2.4, Managing Parameters .
10-16 Forms Services Deployment Guide
10.8.7 Startup Example
This example illustrates an environment of multiple JVMs for multiple applications. As shown in
Table 10–6 , formsweb.cfg is configured with four configuration
sections.
If a user starts an ordersApp application, and the application executes Java code, the Forms runtime process will route the request to the JVM controller named
commonJVM. Because the [ordersApp] application section does not specify which JVM controller to use, the Forms runtime process uses the global one. If the JVM
controller is not started, it will be dynamically started. If a second user starts the same application, it too will attach to commonJVM.
When a user starts an hrApp application and it executes Java code, the Forms runtime process sends the request to the JVM controller named hrJVM because the [hrApp]
application section overrides the global setting. If the JVM controller is not started, it will be dynamically started. When a second user starts the same application, it too will
attach to hrJVM.
Table 10–5 Oracle Forms JVM Controller Startup Parameters
Parameter Description
jvmcontroller Valid values: name of jvmcontroller. In addition, you
can specify no JVM by leaving it blank. Default value: none
Note : In order to specify this parameter in
formsweb.cfg, you must first specify this parameter in otherparams in the form
jvmcontroller=jvmcontroller. For more information on otherparams, see
Table 4–13, Advanced Configuration Parameters
. This parameter can be set globally in the default
section, or any application section can choose to override it. This tells the Forms runtime process which
JVM controller to use. It corresponds to the jvmcontroller parameter for the dejvm executable.
If jvmcontroller does not have a value jvmcontroller=, then the Forms runtime process
will start its own in-process JVM, which means that the Java Importer uses pre-10g behavior.
allowJVMControllerAutoStart Valid values: true, false Default value: true
This parameter enables Oracle Forms to run the JVM controller if Forms is configured to use the JVM
controller which is not already running.
Table 10–6 Multiple JVMs for Multiple Applications
Named Configuration Section JVM Configuration
default jvmcontroller=commonJVM
ordersApp None
hrApp jvmcontroller=hrJVM
salesApp jvmcontroller=
Configuring and Managing Java Virtual Machines 10-17
When a user starts a salesApp application and it executes Java code, the Forms runtime process starts an in-process JVM in the same way the Java Importer works
without JVM pooling. When a second user starts the same application, the application will get their own in-process JVM, thus consuming more memory, as shown in
Figure 10–6 :
Figure 10–6 Multiple JVMs for multiple applications
10.9 JVM Controller Logging
When logging is enabled, the JVM controller logs certain information to the log file:
■
The values of the JVM parameters maxsessions, classpath, and so on;
■
When a JVM controller starts and stops;
■
When a child JVM is spawned;
■
When an Forms runtime process starts a new connection, along with its process ID This is useful for knowing which Forms runtime processes are connected to which
JVM controller for diagnostics or administration;
■
When an Forms runtime process session ends and disconnects from the JVM. This section contains the following:
■
Section 10.9.1, Specifying JVM Default Logging Properties
■
Section 10.9.2, Specifying the JVM Log Directory Location
■
Section 10.9.3, Accessing Log Files
■
Section 10.9.4, Deleting a Log File for a JVM Controller
10.9.1 Specifying JVM Default Logging Properties
Use Fusion Middleware Control to manage the properties for JVM controller logging.
Application Server
Forms Runtime Process
“In-process” JVM
salesApp Client Forms Runtime
Process Forms Runtime
Process Forms Runtime
Process Forms Runtime
Process Forms Runtime
Process
“In-process” JVM
commonJVM
hrJVM
salesApp Client hrApp Client
hrApp Client ordersApp Client
ordersApp Client
