CEMT SET MONITOR

Change the status of monitoring.

In the CICS Explorer, the Regions operations view provides a functional equivalent to this command.

Description

Use the SET MONITOR command to select the classes of monitoring data that you want collected, switch monitoring on or off, and set the status of monitoring options. When you change the status of CICS monitoring from OFF to ON, CICS starts to accumulate monitoring data and to write monitoring records for the active monitoring classes, for all tasks that start after the change is made. The monitoring status of tasks being processed is not affected.

When you change the status of CICS monitoring from ON to OFF, CICS stops writing monitoring data immediately. No monitoring data is accumulated for tasks that start after the change is made. If you turn off monitoring, also set NOPERF to ensure that buffers that contain recorded data for completed tasks are flushed; otherwise, some of this data might be lost.

The monitoring class settings can be changed regardless of whether monitoring is ON or OFF. If monitoring is OFF, you can change the class settings as required in preparation for the next time STATUS is set to ON.

If monitoring is ON, changes to the class settings have the following effects:

Changing a class from inactive to active has no effect on the data written for running tasks.
Changing a class from active to inactive prevents monitoring data for that class being written for running tasks as follows:

PERFORMANCE

Any performance class data remaining in the output buffer is recorded, and no further data is collected.

EXCEPTION

Monitoring data is not written at the completion of the exception condition.

RESOURCE

Any transaction resource monitoring data remaining in the output buffer is recorded, and no further data is collected.

IDENTITY

Any identity class data remaining in the output buffer is recorded, and no further data is collected.

Exception class, transaction resource class, identity class, and performance class data are gathered during the life of a running transaction. When you change these settings, be aware of their impact on transactions that are running. For example, if a transaction is started when the performance class is set to PERF and monitoring is ON, performance class data is accumulated for that transaction. If you switch the performance class to NOPERF while the transaction is running, and then back to PERF before the transaction ends, performance data will be missing from the final monitoring data for that transaction, even though, when it started and when it ended, the performance class was set to PERF. Transaction resource class and identity class data is written at the end of a task, and is written only if the monitoring class is set (to RESRCE for the transaction resource class, or IDNTY for the identity class) at the point when the task ends.

The default is for monitoring records to be compressed, except for identity class records, which are not compressed. If you change the setting for the data compression option, the new setting applies to all monitoring SMF records written from that point onwards, even if they are for a task being processed at the time the change is made. The new setting also applies to any records that are in the buffer waiting to be written to SMF at the time the change is made. The change applies only until a CICS restart, at which time the setting for the data compression option reverts to that specified in the monitoring control table (MCT) controlled by the DFHMCT macro.

Syntax

Press the Clear key to clear the screen. You can start this transaction in two ways:

Type CEMT SET MONITOR (or suitable abbreviations for the keywords). The resulting display lists the current status, similar to that obtained by using the CEMT INQUIRE MONITOR command. You can tab to the highlighted or blank fields and overtype them with the required values.
Type CEMT SET MONITOR (or suitable abbreviations for the keywords), followed by one or more attribute settings that you want to change. For example, cemt s mon on p ex sets CICS monitoring ON and collects performance-class and exception-class data.

Typing ? at the beginning of either the first or second line gives a syntax prompt. Resetting the values takes effect immediately.

CEMT SET MONITOR

Options

COMPRESS: Data compression is performed for monitoring records. The default is for monitoring records to be compressed.
CONVERSE: Conversational tasks have separate performance class records produced for each pair of terminal control I/O requests (Converse or Send/Receive pair).
DPLLIMIT(value): The maximum number of distributed program link requests for which CICS performs transaction resource monitoring. The value specified must be in the range 0 - 64.
EXCEPT: The exception class of monitoring data is collected.
FILELIMIT(value): The maximum number of files for which CICS performs transaction resource monitoring. The value specified must be in the range 0 - 64.
FREQUENCY=(0|hhmmss): The interval for which monitoring automatically produces a transaction performance class record for any long-running transaction that has been in the system for a greater time than the interval. The initial frequency value is set by the MNFREQ system initialization parameter.; The default frequency value is 0, which specifies that FREQUENCY monitoring is inactive; that is, no performance class records are produced for long-running transactions. To produce performance class records for long-running transactions, specify an interval as a 1 to 6 digit number in the format hhmmss, in the range 000100 - 240000. Numbers that are fewer than six digits must be padded with leading zeroes.; CICS can produce a performance class monitoring record in this way only when the long-running transaction is running on the quasi-reentrant (QR) or concurrent (CO) mode TCBs.
IDNTY: The identity class of monitoring data is to be collected.
NOCOMPRESS: Data compression is not to be performed for monitoring records.
NOCONVERSE: Conversational tasks are not to have separate performance class records produced for each pair of terminal control I/O requests (Converse or Send/Receive pair).
NOEXCEPT: The exception class of monitoring data is not to be collected.
NOIDNTY: The identity class of monitoring data is not to be collected.
NOPERF: The performance class of monitoring data is not to be collected.
NORESRCE: Transaction resource monitoring data is not to be collected.
NOSYNCPOINT: A transaction performance class record is not to be produced when a transaction takes an explicit or implicit sync point (unit-of-work), except when the sync point is part of task termination or a sync point rollback.
OFF: CICS monitoring is switched off. When monitoring is OFF, no monitoring data is accumulated or collected, regardless of the settings of the monitoring data classes.
ON: CICS monitoring is switched on. When monitoring is ON, monitoring data is accumulated continuously and is collected (written out to an SMF data set) for each of the classes of monitoring data that is active.
PERF: The performance class of monitoring data is collected.
RESRCE: Transaction resource monitoring data is collected.
SYNCPOINT: A transaction performance class record is produced when a transaction takes an explicit or implicit sync point (unit-of-work), except when the sync point is part of task termination or a sync point rollback.
TSQUEUELIMIT(value): The maximum number of temporary storage queues for which CICS performs transaction resource monitoring. The value specified must be in the range 0 - 64.