Mylyn User Guide - Eclipsepedia

I have been having problems with Mylyn hogging the CPU and making Eclipse unusable. The workaround is to exclude certain parts of the project from being included in Mylyn. I excluded all the generated directories.

Mylyn User Guide - Eclipsepedia: "If an external builder (e.g. Maven, pydev, or other Ant-based builders) is producing output files that are being automatically added to your context because they are not being marked 'derived' as with Eclipse-based builders. You may note that such files are always show as interesting when they are generated or updated and can not be filtered away, since Mylyn expects all files that have changed as part of the task context to have interest. In this case you can explicitly exclude these files from being added to the task context the Preferences -> Mylyn -> Resources page. For example, if the output folder of the builder is 'target', you could set this the following way. Similarly, you could add a filter for '*.pyc' to exclude all files generated with that extension."