This is an attempt to create a resource for weird test failures.

Almost certainly there is a deadlock in the code, or the test is actually using time.Sleep for a long value. You need to fix the test.

Now that the logs are kept in mongo, the debug log code attempts to tail the oplog to get the new logs. Most tests don't set up mongo in replicaset mode, so no oplog collection is created. Most debug-log tests now mock out the oplog with a capped collection for testing purposes.

If you hit this error, you need to either provide a mock oplog, or don't call debug-log.