Configuring the Environment Settings for AIX Platforms Versions

To run native executables such as, a wrapper that launches Java, requires special configuration on AIX. This section lists the environment variables that should be set to improve the performance on AIX.

Following are some configuration parameters that may affect the performance and memory profile of ActiveMatrix and Business Process Management nodes. For details, refer to https://www.ibm.com/support/knowledgecenter/SSYKE2_8.0.0/welcome/welcome_javasdk_version.html for details on Running Java Applications for Java Version 8 on the AIX platform.

Setting the Java Heap Size

The maxdata setting controls the size of the Java heap used by the executable launching the JVM (AMX or BPM Node). The ActiveMatrix and Business Process Management node executables are compiled with maxdata value of 0x80000000. This value can be changed by running the following command: 

ldedit -bmaxdata:<value> tibamx_BPMNode

where <value> is the value of the maxdata; this value can be changed to be unlimited.

Setting the Environment Variables That Have an Impact on JVM Runtime

On AIX, here are some environment variables that have an impact on the JVM runtime:

LDR_CNTRL=USERREGS: Used to set the modType flag to 1L. This improves the performances of the garbage collector.

The following environment variables are suggested by IBM to improve the performance of JVM.
  • AIXTHREAD_SCOPE=S
  • AIXTHREAD_MUTEX_DEBUG=OFF
  • AIXTHREAD_RWLOCK_DEBUG=OFF
  • AIXTHREAD_COND_DEBUG=OFF
The AIXTHREAD_SCOPE=S environment variable is used to bind a user thread to a dedicated kernel thread. If omitted the default behavior is to bind multiple user threads with a single kernel thread. This can cause both concurrency and performance issues. Refer to the IBM documentation for details on the usage of each of these environment variables.