Maintenance
Review: Types of Maintenance Corrective bug fixes, security fixes, etc Adaptive new hardware, new OS, … Perfective adding new functions Preventative Y2K
Where the money goes Rest of Project Corrective Adaptive Functional 33% Rest of Project 40% Corrective Adaptive Functional 15% 12% text page 256
The big questions… Why does so much money go into maintenance? How do we reduce the maintenance costs?
Quality of the software being maintained Foundation One: Package Quality Foundation Two: Maintenance Policy test section 11.2
Does software wear out? errors per KSLOC Time
Does software wear out? errors per KSLOC Time Expected Actual - due to Maintenance Effective
Essential SQA Maintenance Tasks Maintain Accurate Design document Maintain Coding Standards conduct formal code reviews set testing guidelines via a Maintenance Test Plan Track Quality Metrics mean time to correct errors mean time to add new function root causes of errors …