Previous ◁ | ▷ Next

What are Miscellaneous I/Os?

According to the “official” definition from IBM, “Miscellaneous I/Os” contains the count for number of updates, deletes, forced end-of-data, and release operations. However, tests indicate that some below-MI-level data base accesses (typically made by SQL) also are included here. Miscellaneous I/Os are logical I/Os, and updates and deletes will therefore in most cases immediately or eventually trigger a physical I/O.

Our tests show however that FEOD (forced-end-of-data) do not cause any logical I/Os to be reported to GiAPA by the Performance Collector APIs. The same is the case for file positioning (COBOL START, RPG SETLL, etc.).