Note
This parameter was introduced in V4.3.5 BP1.
Description
ob_java_opts specifies the JVM startup options for the Java runtime.
Privilege requirements
Query the parameter
The
systenant and all user tenants can query this parameter by using theSHOW PARAMETERSstatement or theGV$OB_PARAMETERSview.Modify the parameter
Only the
systenant can modify this parameter. User tenants cannot modify this parameter.
Attributes
| Attribute | Description |
|---|---|
| Type | STRING |
| Default value | Empty string |
| Modifiable | Yes. You can use the ALTER SYSTEM SET statement to modify the parameter. |
| Effective upon OBServer node restart | No. The setting takes effect immediately.
NoteJVM startup options are part of the runtime environment configuration. The loading mechanism follows the Java Virtual Machine specification: |
| Required options |
|
Example
Set the JVM startup options in the sys tenant.
ALTER SYSTEM SET ob_java_opts="-Xmx2048m -Xmn2048m -XX:-CriticalJNINatives -Djdk.lang.processReaperUseDefaultStackSize=true -Xrs -XX:+HeapDumpOnOutOfMemoryError -Xloggc:/home/admin/gc.log -XX:+PrintGCDetails -XX:+PrintGCDateStamps -XX:+HeapDumpOnOutOfMemoryError -XX:HeapDumpPath=/home/admin/heapdumps/ -XX:+UseConcMarkSweepGC -XX:+UseParNewGC -XX:CMSInitiatingOccupancyFraction=75 -XX:+UseCMSInitiatingOccupancyOnly -XX:+CMSClassUnloadingEnabled -XX:+TieredCompilation -XX:+ExplicitGCInvokesConcurrentAndUnloadsClasses ";
Notice
Ensure that the /home/observer/heapdumps and /home/observer directories exist. If these directories do not exist, create them manually by using the OBServer deployment user. The paths in this example are for reference only. You can specify other paths based on your actual requirements.