Using complexity-tracking in software development

CATS (Complexity Analysis and Tracking System) is a complexity-tracking system which uses the McCabe complexity analysis tool to construct and maintain an ongoing database of structural complexity values for a software system as it proceeds through its development and testing. Building on previous work which indicated a correlation between structural complexity and defect corrections, CATS allows for a tighter focus of code review efforts such as walkthroughs and inspections and aids in the design of regression, unit, and system tests. CATS has been implemented into the development and testing process for an operation-system software component denoted here as System A. The process for CATS implementation at System A involves two ongoing groups, the BIT (Build, Inspect, and Test) team and the development reams. The BIT team builds the source files, runs CATS, identifies modules for special attention in review and testing, uses the complexity information to design and execute test suites, and reports results to the development teams through a notes-files conference. The development teams use the information in their code efforts, and report their responses and experiences through replies in the notes-file. This creates a body of data, experience, and lessons-learned for use in further development. A CATS analysis has also been carried out for an operating-system facility in VMS (denoted as Facility B).