Entirely for amusement, current timings for 
ackermanns function, ack(3,y):

     Felix Ocaml bytecode  Felix/opt     C -O3  Ocaml native code
---------------------------------------------------------
y=10 113        12             7          1.8          0.4
y=11  ?         50            55         16            2
y=12  ?        220           290        113            9

Times in seconds on 700MHz PIII. 

For y=12, my disk light went on occasionally 
(i.e the process was hitting VM), looks like the size of 
stack frames begins to dominate as y increases?

Be interesting to see comparison with ocaml bytecode/JIT.

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John Skaller, mailto:skaller@users.sf.net
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