Re: Re: Fundamental Benchmarks

To be sure, I've done quite a bit of work on Algorithmic optimization. What was some O(n!) time at first is now O(1) or O(n) (depending on use). But certain implimentation details lead me to need to choose between a Subroutine call vs a 2D-array lookup. I hadn't realized the Array would be so fast, even with 1 million cells. Subroutine calls are far more expensive than I expected. The array implimentation will probably increase the speed of the algorithm by 2-4 times, which makes me very satisfied that I went ahead and checked.

For my purposes, I'm fairly confident, as I imagine that a subroutine will always be a few order of magnitude slower than an Array. All this assuming that my results have any lasting meaning at all, of course. ;)

If people would dedicate a few minutes to look at this on different systems, that would be quite sweet. This particular benchmark ran under Redhat in Perl 5.00503. The box is (I think) a K6-2 250 with 256MB Ram, but I could be wrong on that processor. I'll post an ActiveState 5.6.0 under NT tomorrow if I get a chance.

-Lexicon

Comment on Re: Re: Fundamental Benchmarks

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Happy to oblige by ChemBoy (Priest) on Apr 04, 2001 at 02:04 UTC
This is on an 270 MHz IP-27 (alternatively R12000--I'm not sure which label means more), using Perl 5.004_04. `A = 10 B = 1000000 Benchmark: timing 10 iterations of 1 Nothing , 2 Mult , 3 Array + , 4 Hash , 5 Sub (Ref), 6 Sub (Val)... 1 Nothing : 30 secs (28.53 usr 0.03 sys = 28.56 cpu) 2 Mult : 63 secs (49.93 usr 0.07 sys = 50.00 cpu) 3 Array : 42 secs (37.05 usr 0.04 sys = 37.09 cpu) 4 Hash : 99 secs (95.28 usr 0.09 sys = 95.37 cpu) 5 Sub (Ref): 127 secs (117.77 usr 0.09 sys = 117.86 cpu) 6 Sub (Val): 98 secs (93.28 usr 0.11 sys = 93.39 cpu)` [download] Edit: fixed careless markup (sorry)	[reply] [d/l]

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Happy to oblige
by ChemBoy (Priest) on Apr 04, 2001 at 02:04 UTC

A = 10  B = 1000000
Benchmark: timing 10 iterations of 1 Nothing  , 2 Mult     , 3 Array  
+  , 4 Hash     , 5 Sub (Ref), 6 Sub (Val)...
1 Nothing  : 30 secs (28.53 usr  0.03 sys = 28.56 cpu)
2 Mult     : 63 secs (49.93 usr  0.07 sys = 50.00 cpu)
3 Array    : 42 secs (37.05 usr  0.04 sys = 37.09 cpu)
4 Hash     : 99 secs (95.28 usr  0.09 sys = 95.37 cpu)
5 Sub (Ref): 127 secs (117.77 usr  0.09 sys = 117.86 cpu)
6 Sub (Val): 98 secs (93.28 usr  0.11 sys = 93.39 cpu)
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