Did you know that reftests can consume 6+ days of machine time in
automation for every checkin? (This isn't your fault: just a side-effect of
scheduling everything nearly all the time in automation.)
I just filed bug 1272042 to explore options for reducing reftest scheduling
in automation. I'm not sure if there are prior discussions on this topic. I
do know we have a significant capacity problem in automation right now and
reftests seem like a highly-specialized test suite that doesn't need to run
all the time.
I would very much appreciate the input from layout/reftest domain experts
to determine what can be done, if anything, to schedule reftests less
frequently and put less burden on our automation. Please reply in the bug.