The mac test load currently sits at 16K which is unsustainable. The bulk of that is on try, which due to priority, does not complete because tasks on trunk has higher priority, since the tasks expire in a day https://queue.taskcluster.net/v1/pending/releng-hardware/gecko-t-osx-1010 There are several contributing factors to this 1) Stylo tests were recently enabled for non-stylo builds with a flag in bug 1374748. These were enabled on trunk. Previously they were enabled only on m-c. Our mac machine pool cannot keep up with this 2) The data for these new tests is not enabled in seta so the full suite of tests is running on these branches Remedies to the load 1) Disable macosx stylo tests on trunk bug 1386264 (done) 2) Fix seta so fewer tests run bug 1386405 3) Turn off these tests on autoland or add a filter for autoland so they only run when stylo is touched bug 1386405 4) Disable non-e10s tests (have to find bug, apparently jmaher will tackle this bug soon)

pmoore is also working on coalescing for OS X which should help with non-try load in bug 1382204.

Dustin is working on allow optimizing out whole platforms when changes are limited to a single directory in bug 1383880

:jmaher is there a bug for the work to disable all non-e10s tests, I couldn't find it

I just filed it this morning: bug 1386689

Note explaining the priority level: P4 doesn't mean we've lowered the priority, but the contrary. However, we're aligning these levels to the buildduty quarterly deliverables, where P1-P3 are taken by our daily waterline KTLO operational tasks.

All dependency bug are solved,macosx test load are now more sustainable so I'll mark this bug as resolved for now,of course we can reopen the bug any time if other issues are spotted.