MacOSX Performance

Karsten Wolf karstenwo at
Fri Jan 21 21:31:14 UTC 2005

Am 21.01.2005 um 14:34 schrieb Stéphane Conversy:

> I guess the problem comes from the display engine.

Guessed right. Or more precisely It has to do with the fact that the vm 
calls for a display update for every bitblt. Since these update calls 
are interprocess calls on OSX (VM to WindowServer) they become very 
expensive in terms of time if the vm does that for every pixel.

You're seeing the slowness especially when drawing lines. In that case 
the display update is called for every pixel which brings the 
performance down to the 1% area. You won't see it in cases where the 
update covers a bigger area. The FreeCell test (selecting game 1) 
should be comparable to the windows vm.

> - the vm is the same for all machines,
I think not. AFAIK the official windows vm has some kind of display 
deferring included.

I have a modified & still buggy vm which i can email you if you're 


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