SYSTEM.DEFAULT.INITIATION.QUEUE Question

[R. Dirk Tolson]

I have a new message flow that is confusing me.

The source is MQ 2.1 on MVS. Persistent messages
are routed to MQ 5.3 on Solaris. Occaisonally an event
occurs that throws a monkey wrench in things.

Today MVS went down and the system had to be IPLed.
For some reason a larger than normal number of messages
were sitting in the XMIT queue, 24000. On the Unix side
the messages were handled until the
SYSTEM.DEFAULT.INITIATION.QUEUE reached its
maximum depth of 1000, then everything stopped. By
starting and stopping the qmgr I could force another 1000
or so messages to be processed until the
SYSTEM.DEFAULT.INITIATION.QUEUE reached its max
depth again.

My main question is what is happening? When the init queue
is full some kind of events seem to stop. I guess I could just
bump the maximum depth of the init queue up to some ridiculous
number, but that doesn't feel right.

I seem to be missing a key principle here. Can anybody clue me in?