VTK/SoftwareQuality/NightlyExpectedBuildTestFailures

The VTK Nightly Expected builds show the status of VTK on VTK supported platforms at a fixed time each day. Although the Gerrit Review Process and Continuous Builds attempt to catch build defects early, it is the Nightly Expected builds that show the health of VTK on a broader collection of systems. Recurring nightly failures make it difficult for a developer to see if her changes have affected the spectrum of platforms.

This experiment uses the DMAIC methodology of the Six Sigma management process to "Define", "Measure", "Analyze", "Improve" and "Control" to resolve these issues.

The basic methodology (from Wikipedia) consists of the following five steps:

• Define process goals that are consistent with customer demands and VTK's strategy.
• Measure key aspects of the current process and collect relevant data.
• Analyze the data to verify cause-and-effect relationships. Determine what the relationships are, and attempt to ensure that all factors have been considered.
• Improve or optimize the process.
• Control to ensure that any deviations from target are corrected before they result in defects. Set up pilot runs to establish software quality, move on to production, set up control mechanisms and continuously monitor the process.

Define

Keep the number of VTK Nightly Expected recurring test failures(defects) to 0. When the defects are above 0, developers find it difficult to notice that their changes introduce new defects.

Measure

As of February xx there were xx defects on the xx VTK Nightly Expected builds:

Improve

The following Gerrit reviews addressed the defects.

Control

Once reduced to 0, developer diligence is needed to keep the defects to 0.