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[Zarkonnen]

Spurred on by this post, here is an in-depth post on memory management in Airships.

Excerpt:

The game is written in Java, where unused data is automatically deleted in a process called garbage collection. This is nice, but comes with a big drawback: you can't control when garbage collection (GC) happens, and it can take too long.

The game runs at 60 frames per second, giving each frame a bit more than 16 milliseconds to advance the game state and redraw the screen. If GC kicks in during a frame and takes 30 milliseconds, the game stutters noticeably.

So this is something that needs fixing.

Read the rest

[Chromanoid]

Nice article, yet I doubt object creation is that problematic with a modern JVM. Especially short lived objects usually should not affect performance, see http://programmers.stackexchange.com/questions/149563/should-we-avoid-object-creation-in-java

Relevant thread: http://forums.tigsource.com/index.php?topic=22054.0

[MontyOnTheRun]

Amazing references. My universe has just expanded! 
Hours and hours to read.

[Julien]

Thanks a lot !!

[Zarkonnen]

Nice article, yet I doubt object creation is that problematic with a modern JVM. Especially short lived objects usually should not affect performance, see http://programmers.stackexchange.com/questions/149563/should-we-avoid-object-creation-in-java

Relevant thread: http://forums.tigsource.com/index.php?topic=22054.0

And yet it did make a difference, as the spikes in frame times went away...

[Chromanoid]

I see. I hope this will change in future versions of the HotSpot compiler. This "short-lived objects don't matter" thing is preached for a while now -.- For stuff like Vector calculations where you throw away the object after leaving the method scope you might want to have a look at JStackAlloc.

[Julien]

It might be irrelevant, or specific to Dalvik, but in the google dev doc it is recommanded to use the enhanced for each loop. Yet this article recommand the opposite. Honestly I've used both in my game and didn't mesured any difference.

I came to get(i) because of the same reason, iterators, but the comment in the google doc always troubled me.

[MontyOnTheRun]

Julien, I remember reading this and changing my code base to comply with it. Gains were modest, but visible. I don't have numbers now, but I would say it jumped from something like 18 FPS to 20 FPS.

[Julien]

Thanks for your feedback !