The parallel suite runs several tests simultaneously against an instance of mongod. It randomizes the grouping and order of the tests on each run, which helps to exercise the code.

However, when announcing failure of the master test suite, it doesn't identify which test failed, or what other tests were running at the same time. Moreover, there is no way to reproduce a particular failure, because the random seed is not reported in the log and there is no way to tell the test to use a particular seed.

This test suite would be more useful if it summarized the failure at the end of the run and identified the failing test(s), and it would be more useful if it gave developers a way to re-run a failed test so that a fix could be verified. As it is, the test might work (or fail) on the next run and we don't know that anything has changed, because the actual test run is different.