When any of the following conditions occur, message queuing stops,
and the system posts an ECB.
- No more storage remains in the message data space. The size of
the storage area was specified in the STORAGE field of MCSOP.
- The maximum number of messages was reached in the message data
space. The maximum number was specified on the QLIMIT parameter of
the MCSOPER macro.
The ALERTECB parameter on the MCSOPER macro specifies the ECB
to be posted when message queuing stops.
When MCSOPER posts the ECB, check the MCS console status area,
MCSCSA to determine why queuing has stopped. If the message data
space is full, the MCSCMLIM field contains a 1. If the maximum number
of messages has been reached, the MCSCDLIM field contains a 1. In
either case, to start message queuing again, retrieve messages from
the MDB by issuing the MCSOPMSG macro.
Issue the MCSOPMSG macro with the REQUEST=GETMSG parameter a sufficient
number of times to retrieve enough messages to meet the QRESUME percentage
specified on the MCSOPER macro. For example, if on MCSOPER you defined
QLIMIT as 1000 messages, and QRESUME at 50%, queuing stops when the
message storage area holds 1000 messages and the system is queuing
one more message into the area. You can restart queuing in one of
two ways:
- Issue MCSOPMSG REQUEST=GETMSG 500 times so that the area holds
500 messages, or 50% of 1000. Queuing automatically resumes when the
area holds 50% of the QLIMIT.
- Issue MCSOPMSG REQUEST=GETMSG any number of times to reduce the
number of queued messages, then issue MCSOPMSG REQUEST=RESUME to restart
queuing. Queuing will continue until you again hit the QLIMIT.
The system does not resume queuing if queuing stopped because the
message data space reached the storage limit as defined for the storage
attribute in MCSOP, a security product's user segment, or the system
default.
Occasionally, the ALERTECB can be posted for one of the following
conditions as well:
- An internal queuing error has occurred and message queuing has
stopped. The MCSCSA internal error field will contain a 1. Issue
MCSOPMSG REQUEST=RESUME to restart queuing.
By issuing MCSOPMSG REQUEST=RESUME, you can resume queuing to the
message data space after any abend that suspends system message queuing,
or after the failure of recovery routines invoked. Some or all messages
currently queued might be lost. REQUEST=RESUME enables you to resume
queuing without having to retrieve enough messages to reach the QRESUME
percentage.