Statistical recording

Error statistics, the number of times I/O devices have failed for specific device-dependent failures, are kept in a main storage table called the device statistics table. The device's error recovery procedure (ERP) updates the table.

Note: Intermediate counters for buffered log devices, such as the IBM® 3330 and 3850, are kept in the device's error recording buffer and are updated by the device's ERP. An overflow condition or end-of-day (EOD) request on these devices causes the information to be recorded on the logrec data set as an MDR record.