ExitPropertiesLocal stanza of the qm.ini file

Use the Cluster queue manager properties page from the IBM MQ Explorer, or the ExitPropertiesLocal stanza in the qm.ini file, to specify information about exit properties on a queue manager. Alternatively, we can set it using the amqmdain command.

By default, this setting is inherited from the CLWLMode attribute in the ExitProperties stanza of the machine-wide configuration (described in ExitProperties stanza of the mqs.ini file ). Change this setting only if we want to configure this queue manager in a different way. This value can be overridden for individual queue managers using the cluster workload mode attribute on the Cluster queue manager properties page.

CLWLMode= SAFE|FAST

The cluster workload (CLWL) exit specifies 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 we 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 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 can affect performance.

FAST

Run the cluster exit inline in the queue manager process.

Specify 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. We should only run the CLWL exit in FAST mode if you are convinced that there are no problems with your CLWL exit, and we are particularly concerned about performance.

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

Parent topic: Attributes for changing queue manager configuration information