Re: [computer-go] Pattern Matcher

[Vincent Diepeveen <diep@xxxxxxxxx>]

This connect4 has the most idiotic and slow hashtable implementation i have
ever seen in my life.

He's using the SLOWEST possible integer instructions on the processor for
what is it 5 times or so just for 1 hashtable lookup or so?

modulo and divide are like a 46+ cycles at opteron, and like 200 cycles or
so at a P4?

You can execute otherwise 600 instructions on the paper, but for sure 200
in that time.

Additionally why not use a more clever hashtable probing system?

My connect4 had a more clever one back in 1995 already or so.

Also you shouldn't take too much hash for such simplistic L1 cache programs.

Lookup to L2 cache is still possible to suffer as that's 13 cycles on
opteron and 20 cycles at K7. Already 28+ at P4.

But main memory is like 400 nansoseconds at my poor K7, multiply with
2.127Ghz for number of cycles. And even at dual opteron it's like 133
nanoseconds.

If you can't optimize for such SIMPLISTIC details, you sure must code the
rest of your life JAVA.

Vincent
_______________________________________________
computer-go mailing list
computer-go@xxxxxxxxxxxxxxxxx
http://www.computer-go.org/mailman/listinfo/computer-go/