Hi Monks,
Please look at the following short example.
It measures (hopefully...) the time it takes perl to return from the DoIt subroutine. If you scale the value of $max, the time will expand linearily (well, at least on ActivePerl 5.8.8 on XP OS).

Is there any way to reduce this time?


For those that needed more explanations:
This is the problem re-defined:
When calling a sub that uses large data structures (no matter what it does), what general measures one can to reduce the effect of the garbage collection.
For a good answer, see liverpole's below. 
#!/usr/bin/perl -w
my  $func_done;
my  $func_return;

my $max=1000000;

DoIt($max);
$func_return = (times)[0];
printf "Return took %.4f CPU seconds\n", $func_return - $func_done;

sub DoIt{
        my $limit=shift;
        my $i;
        my %myhash;
        foreach $i (0..$limit){
                $myhash{$i}=1;
        }
        $func_done = (times)[0];
        return;
}

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In reply to Garbage collection at subroutine return by tcarmeli

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