Clearing WebSphere MQ shared memory resources

When a WebSphere MQ queue manager stops, it releases the IPC resources that it was using back to the system. There are two situations in which this might not happen automatically:

• If applications are connected to the queue manager when it stops (perhaps because the queue manager was shut down using endmqm -i or endmqm -p), the IPC resources used by these applications might not be released.
• If the queue manager ends abnormally (for example, if an operator issues the system kill command), some IPC resources might be left allocated after all queue manager processes have terminated.

In these cases, the IPC resources are not release back to the system until you manually remove them, or restart (strmqm) or delete (dltmqm) the queue manager.

WebSphere MQ provides a utility to release System V IPC resources allocated by the queue manager but not freed, for one of the above reasons, back to the system.

To check and free any unused System V IPC resources, type (as an authorized user, mqm or root):

On Solaris, HP, Linux

/opt/mqm/bin/amqiclen

On AIX

/usr/mqm/lib/amqiclen