Game slowness

Question

Hello all,
Been pestering a friend of mine with my latest game attempt so I thought I'd pester the
general public now. Seems the game ran a bit slow on his machine, but things seem to
be running fairly smoothly for me. Now his machine may not be a high end, super sonic
beast, but the way I see it a wrist watch should be able to run a half assed attempt at this game
without missing a beat. Anyways I thought I'd ask nicely if some of you could give it a try:
http://home.chello.no/~ttollefs/game/hyh/hyh.html
Oh and just to keep us all on the straight and narrow let's not get into any poor AI implementation :)
(unless it could be causing the game to slow down ;) ). I know there are a few bugs here and
there, but hopefully you won't get to see any of 'em when you test it.
Oh, and the Hi-Score won't be stored so don't put "Break Hi-Score" on the top of your ToDo list.

Answer 1

Just noticed that half second hang up, but it doesn't seem to appear when I
run the game locally. I'll fiddle a bit with HPROF and see if I get any useful output.
I set the game to run at 30FPS and used this game loop to control it
public void run()
     int frameCount = 0;
     long startTime = System.currentTimeMillis();
     while(true)
             gameCycle();
          frameCount++;
          while((System.currentTimeMillis()-startTime)/m_iFrameDelay < frameCount)
          {   Thread.yield();   }
}This is a slightly butchered version of a game loop I found in this forum, which was
using nano seconds (don't have the 1.5 sdk so I changed it). I checked the Windows Task
Manager when the game was running and it reported a 100% CPU usage so I switched
back to my previous game loop
public void run()
     while (true)
          try
          {   sleep(m_iFrameDelay);   }
          catch(InterruptedException ie)
          {   System.err.println("m_iFrameDelay was interrupted");   }
          gameCycle();
}which used around 5-10 % of the cpu, but the game seems to run just as well regardless of the
two versions.
As for the friend's JRE version I suspect that its not up to date so that could explain the
slowness on his machine.