If MHP calls the function dc_mcf_execap() of timer start, MCF fetches messages from the output queue and performs timer monitoring. If a timer monitoring error, scheduling error, or the like reports during the wait time before writing in the input queue, ERREVT4 occurs. After that, the MHP to process ERREVT4 is started.

The figure below shows the outline of ERREVT4.

Figure 3-24 Outline of ERREVT4

1. The function dc_mcf_execap() of timer start is called. If the transaction commits it, MCF starts timer monitoring.
2. If a failure reports during timer monitoring by MCF, ERREVT4 reports.
3. ERREVT4 schedules the MHP for ERREVT4 via the input queue.
4. The MHP for an MCF event analyzes and processes ERREVT4.