MROBTCH

The MROBTCH system initialization parameter specifies the number of events that must occur before CICS® is posted for dispatch because of the batching mechanism.

MROBTCH={1|number}
The number can be in the range 1 through 255, and the default is 1.
Use this batching mechanism to spread the overhead of dispatching CICS over several tasks. If the value is greater than 1 and CICS is in a system wait, CICS is not posted for dispatch until the specified number of events has occurred. Events include MRO requests from connected systems or DASD I/O and CHANGE_MODE processing. For these events, CICS is dispatched as soon as one of the following occurs:
  • The current batch fills up (the number of events equals MROBTCH)
  • An ICV interval expires
Therefore, ensure that the time interval you specify in the ICV parameter is low enough to prevent undue delay to the system.

If CICS is dispatched for another reason, the current batch is dealt with in that dispatch of CICS.

Note: During periods of low utilization, a value of MROBTCH greater than 1 might cause increased transaction response times. Transactions that issue file I/O requests might be delayed because of increased FCIOWAIT value. For more information about the effect of MROBTCH on performance, see Batching requests (MROBTCH).