Change-Based Test Management (CBTM) is a software validation methodology centered on monitoring change to maximize the effectiveness of the validation cycle. Intel Corporation developed CBTM starting in January 2001 to help validate the graphics drivers created for Intel s integrated chipsets. The increasingly large number of supported motherboards and operating systems was making validation more and more difficult. At the time, we were working in the software validation group and we needed a way to increase the effectiveness of our validation effort while maintaining the same resource costs.

With a limited number of people and a limited amount of time it became clear that we needed to make our test cycles more effective in order to accommodate the growing number of products. We concluded that the only way to become more effective was to start testing smarter. We needed a way to monitor exactly what we were testing and what changes were occurring in the driver code. That is where code coverage and code deltas came into play.

With code coverage, we were able to get a better understanding of our test suites. We knew each test targeted specific functions, but we did not know whether these tests were doing what we thought they were doing or if they were doing other things as well. Code coverage answered these questions for us and gave us a better understanding of the code base and which areas were the most complex. This allowed us to begin to manage...