INTERVAL

Read syntax diagramSkip visual syntax diagramINTERVAL(30M)INTERVAL( mM)

Specifies the length of the Start of changez/OS® Data GathererEnd of change SMF interval, where m is a divisor of 60, and M is minutes. This means that interval values of 1, 2, 3, 4, 5, 6, 10, 12, 15, 20, 30 or 60 minutes are possible, all of them meeting the SYNC value at least every hour.

At the end of the interval, the system dispatches Monitor I. Monitor I summarizes the recorded data and formats it into an interval report, or an SMF record, or both (see the Monitor I REPORT and RECORD options).

Note:
Start of changez/OS Data GathererEnd of change processes this session option only if it is used in conjunction with one of the following SYNC options: 
SYNC(RMF,mm)
SYNC(RMF,mmM)
NOSYNC

With SYNC(SMF), which is default, INTERVAL is ignored.

The default is 30 minutes (30M). The valid range for INTERVAL is from a minimum of one to a maximum of 60 minutes. If you specify less than one minute, Start of changez/OS Data GathererEnd of change increases the value to one; if you specify more than 60 minutes, Start of changez/OS Data GathererEnd of change decreases the value to 60. To synchronize the Start of changez/OS Data GathererEnd of change SMF interval to any time within the hour, use the Monitor I SYNC option. See Synchronizing SMF recording intervals for more information.
Notes:
  1. If you specify a STOP option, be sure that the value used there is equal to or greater than the INTERVAL value. Otherwise, Start of changez/OS Data GathererEnd of change sets the STOP value to the INTERVAL value.
  2. Monitor I extends INTERVAL in two situations:
    • When the system does not dispatch Monitor I at the end of the interval.

      If Monitor I is executing and does not get control within the specified interval length, Monitor I extends the length to 99 minutes. If Monitor I still does not get control within the 99 minutes, data collection is skipped for that interval, and a message is issued to the operator. This can happen when the dispatching priority for Start of changez/OS Data GathererEnd of change is too low; see Setting up the RMF control session and monitoring sessions for information about how to change the dispatching priority.

    • When you stop the processor during the interval.

      If the processor is stopped during the interval, the interval length can also exceed 99 minutes. To avoid missing data collection, stop the monitor session or RMF control session before stopping the processor.