ExitProperties stanza of the mqs.ini file

Use the ExitProperties stanza in the mqs.ini file to specify configuration options used by queue manager exit programs.

Alternatively, on Linux® (x86 and x86-64) and Windows, use the IBM® MQ Explorer Extended IBM MQ properties page.

CLWLMode= SAFE (default) |FAST

The cluster workload (CLWL) exit allows you to specify which cluster queue in the cluster to open in response to an MQI call (for example, MQOPEN, MQPUT). The CLWL exit runs either in FAST mode or SAFE mode depending on the value you specify on the CLWLMode attribute. If you omit the CLWLMode attribute, the cluster workload exit runs in SAFE mode.

SAFE

Run the CLWL exit in a separate process from the queue manager. This is the default.

If a problem arises with the user-written CLWL exit when running in SAFE mode, the following happens:

• The CLWL server process (amqzlwa0) fails.
• The queue manager restarts the CLWL server process.
• The error is reported to you in the error log. If an MQI call is in progress, you receive notification in the form of a return code.

The integrity of the queue manager is preserved.

Note: Running the CLWL exit in a separate process might affect performance.

FAST

Run the cluster exit inline in the queue manager process.

Specifying this option improves performance by avoiding the process switching costs associated with running in SAFE mode, but does so at the expense of queue manager integrity. You should only run the CLWL exit in FAST mode if you are convinced that there are no problems with your CLWL exit, and you are particularly concerned about performance.

If a problem arises when the CLWL exit is running in FAST mode, the queue manager will fail and you run the risk of the integrity of the queue manager being compromised.