Weird rumble scores

I'm curious why you think GC overhead is always fair. Since GC overhead happens outside of the main thread, it can punish all robots in the same battle with a high degree of randomness. Not only that, if you're running a bunch of rumble clients on a computer, and the overall CPU usage on the system for all cores reaches 100% due to a couple clients having more GC overhead, then it could affect all bots in all active battles on that system, even in the other rumble clients.

Being fair means no one is getting advantage over it. And the ability to withstand ocationally skipped turns is part of the competition.

Since no one can guarantee that robots are always running with sufficent resource, I’m always on the side that robot authors should assume low performance computers.

"no one is getting advantage over it" is certainly untrue. Consider the notion of a bot that uses very little CPU in the main thread but creates lots of GC overhead, in a battle versus a bot that uses most of the typical CPU allotment but doesn't create much GC overhead. If this is on a system where the GC thread can affect the time available to the main thread (i.e. don't have enough spare CPU for the GC thread), then the bot that uses very little CPU in the main thread but is creating lots of GC overhead will be advantaged by causing the GC overhead, since it would cause more skipped turns for the other bot but not so much itself. This is somewhat of an extreme example, but the point is that skipped turns caused by GC overhead are anything but fairly distributed.

For the specific case I mentioned of ags.Glacier 0.3.0 versus lxx.Emerald 0.6.5, when it was at 1 battle, I thought it was likely some rare exception as you say, but then a 2nd battle came in with about the same low score as the 1st battle, and yet I'm not able to reproduce a result anything like that in many many tests. This leads me to believe that there is most likely something significantly different about the environment those two battles were run in, as compared to my own environment.

I think there must have been a bad client running at some point. BeepBoop 0.14a is identical to 0.14, but is getting 0.3 points better in the rumble now. Even weirder, I just noticed that BeepBoop 0.13 has 85% against eem.awful, which disables itself at the beginning of each battle!

Let’s wait more battles, if the score goes down to some similar APS after ~30000 battles, then every body’s client is fine.