[igt-dev] [PATCH i-g-t] runner/resultgen: Provide output when test output is completely empty

[Chris Wilson]

Quoting Petri Latvala (2020-02-19 12:19:40)
> If a machine is hard-hanging or otherwise rebooted at the correct
> time, intermediary output files get created but nothing ever gets
> written to them. That yields results that are completely empty and
> hard to categorize or even sometimes detect automatically. Handle this
> corner case explicitly with a custom text explaining what might have
> happened to prod result analysis towards fixing the real issue instead
> of wondering if test result processing is faulty.
> 
> The race for getting empty files is easier to hit than it seems. The
> files get created by the runner before calling exec(), and there's
> plenty of time to hit a really hard crash.

Speaking of which, it would not be terrible if igt_runner periodically
called sync() everytime it decided there were new logs to preserve.
We should also probably remove/reduce the writeback delay.
-Chris