I ran a CL via perf trybots.
In many cases, some (or all) the bots are purple. Like this:
https://codereview.chromium.org/1870993003/

When I click to the purple bot the Performance Test (With Patch) 1 of 1 has failed after 1h, but there is no stdio.
Example here:
https://build.chromium.org/p/tryserver.chromium.perf/builders/android_nexus7_perf_bisect/builds/2897/steps/Performance%20Test%20%28With%20Patch%29%201%20of%201/logs/stdio

How can I figure out what's going on?