In the course of writing a health check for MQ and IIB this week, I was reminded of some log tuning mystique that we resolved at Hursley concerning queue buffers. As detailed elsewhere, DefaultQBufferSize is the TuningParameters stanza value that determines the size of the non-persistent buffer of a queue. The queue's non-persistent buffer will adopt the size of this parameter based on the value this was set to in the qm.ini when the QM was last started, but before the queue was created. If this value is not set in the qm.ini at that time, then the default value is 128KB. So far, this is pretty much aligned with the 'received wisdom', as long as you looked under the right stone. What is not generally known is that the queue persistent buffer 'equivalent' is not DefaultPQBufferSize (which I will describe shortly), but NewPQBufferSize! NewPQBufferSize: The persistent buffer of a queue will be set to whatever value was when the QM was last started and before the queue
So, in the tips and tricks that are out there, you will find suggestions on how to set up an MQ queue manager as a systemd service. Here is a quick refinement for a slightly more robust version and the inclusion of an IIB (or ACE) integration node. The following shows the necessary settings and commands (and tests the service). This works with integration nodes that are associated with queue mangers of the same name. (A practice I have personally adopted for a good few years - for numerous good reasons, including the fact that is simple to remember.) These are scant notes, but you should be able to 'read between the lines'. Enjoy! crtmqm -ld /var/mqm/log -md /var/mqm/qmgrs -lf 16384 -lc -lp 5 -ls 5 -u SYSTEM.DEAD.LETTER.QUEUE TEST strmqm TEST mqsicreatebroker TEST -q TEST -w /var/mqsi -o advanced -s inactive endmqm TEST Switch to root: su - intadm belongs to mqm (primary group) and mqbrkrs vi /etc/systemd/system/mq@.service [Unit] Description=IBM MQ queue manager %I After=ne