Note
This parameter is available starting with V4.3.5 BP1.
Description
ob_java_opts specifies the JVM startup parameters for Java.
Privilege requirements
Query the parameter
You can use the
SHOW PARAMETERSstatement or theGV$OB_PARAMETERSview to query this parameter in the sys tenant and all user tenants.Modify the parameter
Only the sys tenant can modify this parameter. User tenants cannot modify this parameter.
Attributes
Attribute |
Description |
|---|---|
| Type | STRING |
| Default value | An 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 parameters are basic runtime environment configurations. They are loaded according to the Java Virtual Machine (JVM) specification: |
| Mandatory items |
|
Examples
In the sys tenant, run the following command to enable or configure the parameter.
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
Make sure that the /home/observer/heapdumps and /home/observer directories exist. If these directories do not exist, you must manually create them as the deployment user of OBServer. Note that the path in this example is for reference only. You can specify other paths as needed.