What is contained in the Subsystem Analyzer FMT_WIO column?

Products

• RC Compare for DB2 for z/OS
• Bind Analyzer for DB2 for z/OS
• SQL-Ease for DB2 for z/OS
• SYSVIEW Performance Management Option for DB2 for z/OS
• Plan Analyzer for DB2 for z/OS
• Subsystem Analyzer for DB2 for z/OS
• Database Analyzer for DB2 for z/OS
• Fast Unload for DB2 for z/OS
• Fast Check for DB2 for z/OS
• Fast Index for DB2 for z/OS
• Rapid Reorg for DB2 for z/OS

Issue/Introduction

Introduction: 

This article describes what is contained in the Subsystem Analyzer FMT_WIO column.

Question: 

What is contained in the Subsystem Analyzer FMT_WIO column?

Environment:  

z/OS 1.11 and above.

Answer: 

This column contains a count of the DB2 pre-formatting I/O's of new pages in a table space during execution time.

A common reason would be Inserts which cause new extents to be built and new pages to be formatted by DB2. 

Additional Information:

If the PREFORMAT option is used in a LOAD or REORG utility, depending upon the size of the object, this could generate a substantial amount of "Format Write I/O's".

Environment

Release:
Component: PSA