I'm not sure that a memory hogging recursive function makes for a fair benchmark of function calling speed (even if the tail recursion could be optimized away in another language -- and if the tail recursion could be optimized away, you wouldn't be calling the function anymore, you'd just be doing a goto). I think this version of func_test.pl is more fair (which attempts to test the speed of function calling rather than memory allocation):
#!/usr/bin/perl

#sum of number between 1 and 1,000,000
$n = 1_000_000;

my $t = 0;

$t = addup( $t, $n-- ) while $n;
print "$t\n";

sub addup
{
    $_[0] + $_[1];
}

[download]
and then the two come out closer:
$ time ./func_tst.pl
500000500000

real    0m5.68s
user    0m5.48s
sys     0m0.02s
$ time ./loop_test.pl
500000500000

real    0m1.48s
user    0m1.47s
sys     0m0.01s

[download]

In reply to Re^5: Performance, Abstraction and HOP by runrig
in thread Performance, Abstraction and HOP by pg

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