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Fragment of a discussion from Talk:RoboRumble
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Running the rumble client on an ultrabook when I'm not using it and it is plugged into power. Often it uses 2 cores even with a single client. CPU constant is about 5.3ms in openjdk8 using Linux.

About the skipped turn thing, I agree. A big part of Robocode is how long you have to do your processing in. It is a massive tradeoff and I know some of my bots occasionally step over the edge. However, I also don't want to change the rules of the competition. If there is something in Oracle JDK8 that is killing certain bots we need to figure out what that is.

Skilgannon (talk)19:43, 4 September 2017

I am not arguing that heavy on skipping bots should not be punished, my complain that it is erratic and seemingly coming from Java itself. Looks like it shows when a heavy bot is matched against a low CPU demanding one.

By the way, sometimes it to my advantage. I see strange unexplainable APS gain in melee against 'sgp.JollyNinja 3.53' [1]

Note that my v7.4 is very mediocre when compared against v6.1, except one case JollyNinja.

Beaming (talk)20:09, 4 September 2017

Heavy vs light causing problems sounds to me like a race condition. And I think this might even be a separate issue from MoxieBot getting 0. This clearly needs further investigation.

Skilgannon (talk)20:39, 4 September 2017

I took a look at your results. Your bot is performing below expectations, most prominently with 37.71% survival against sample.Crazy (???), which I cannot reproduce on my own computer.

I do agree that bugs (particularly ones that produce unfair results) ought to be squashed ASAP. However, you cannot expect the amount of work-per-turn your bot is allowed to perform to remain constant between machines (and possibly not even between battles or rounds). Perhaps a CPU-intensive background process is running, or the user decides to play video games, or the OS starts throttling Java, or the CPU drops to 0.15 GHz for no good reason (I've actually seen that happen), or gamma rays hit your computer and flip a bit in the tick time counter, or whatever.

My point was that high-CPU bots must adapt to changing circumstances. Too many bots just ignore SkippedTurnEvent, when it's practically a blaring flashing-red-lights warning from Robocode. You could respond by reducing CPU load, e.g. disabling features, virtual guns, second wave surfing, etc. It's better for your bot to function suboptimally than to not function at all.

MultiplyByZer0 (talk)21:18, 4 September 2017

Agreed that the SkippedTurnEvent is mostly ignored, and that more could be done on this side. However, there is a reason that we have the CPU calibration, and that is because we want all environments to be similar. It is impossible to get consistent results if on one computer you can do second wave surfing with precise intersection and KNN gun with Gaussian kernel density estimation, and the other you have to fall back to single wave and a simple VCS gun. It would require all rumble battles to be contributed by a single machine, and then we are back to a standard environment.

Skilgannon (talk)23:36, 4 September 2017

While I take the blame for my bot performance.

I would claim that I am not ignoring the skip turn event. I have a counter for it, and I release bots which keep it low through the game. Typically in the rumble, it reports zero about every second round in 35 rounds game, in 45% rounds it is 1; in 2 or 3 rounds it spikes up to 7 or even 15 per round. Even 15 skips per 700 turns games is not too much to loose a game to sample.crazy with HoT gun.

So I still think it is the "Thread.Death" which is probably triggered by skipped turns.

I will try to reduce the bot CPU demand and see if the problem goes away.

Beaming (talk)02:42, 5 September 2017

ThreadDeath is just Thread.stop() doing its job.

See this article.

MultiplyByZer0 (talk)01:48, 6 September 2017

Are we actually talking about time-per-turn problem? I supposed, given the age of Robocode and Roborumble, that this is a well discussed topic and that every possible decision to make the system work fair enough while providing the "contributing" feature was already made. It seems that what we are talking about here is a bug. I know every environment is not equal, but even with the very little time I have on Robocode I could conclude a robot should work under the assumption that at least a reasonable quota of its turn time will be respected (even if in reality it's not eventually). If that quota is not being respected even after like, 10 battles, in a machine that is OK, and the results are absurd like the results Beaming reported, there must be a bug somewhere, even if it's on Beaming's side, and IMO it's worth it to discuss it and, maybe, to find it, since it may explain some other weird behavior in the future.

Rsalesc (talk)02:13, 5 September 2017