Once the project has begun, the analysis of software
measures becomes a major concern. Analysis is conducted to determine whether
software development efforts are meeting defined plans, assumptions and
targets. Planned and actual performance data are the inputs to this process.
Performance analysis should be viewed as an investigative process used to
identify risks, manage risks and track down and isolate problems. This may
require the use of slightly different data, the use of different measures to
generate different indicators and the identification of alternative courses of
action each time performance is analyzed.
Many times schedule, resources,
growth, or quality trends are not recognizable as an indication of a potential
problem until the associated risk has actually become a problem of major
proportions. Because software risks are not independent, an integrated
analysis using multiple indicators should be performed. In combination,
Figures 7-1 and 7-2 show an example of a potential problem made visible by
detecting inconsistent trends using multiple indicators. Figure 7-1 shows an
indicator for the measure “Component Status” during the design process and
Figure 7-2 shows an indicator for the measure “Problem Report Status” for the
same project. Whereas the measure of actual component status appears to be
only slightly behind the plan, the discrepancy between the number of open and
closed problem reports is increasing. These open problem reports represent
rework that must be completed before the design activity can be completed.
Thus, the trends in these two performance indicators are inconsistent, an
indication of a potential problem.
Once a potential problem has been identified, it should be
localized by examining indicators with more detailed data. In the example just
cited, a Problem Report Status chart should be generated for each of the
Configuration Items within the software design. Identifying the specific
source of the potential problem helps to determine the rot cause and selection
of the appropriate corrective action(s).