perlquestion
monktim
According to the Learning Perl book, truncating an array does not recover its memory. To feee memory I need to undef the array like this undef(@array). It also says that the memory doesn't always get free because not many operating systems support this. I find this strange as I've never had this problem in other languages.<p>
I'm using Win2K and not much memory gets free when I undef my array. When I run the script below the @array takes ~76,000K in memory when I hit the breakpoint. After undef(@array) gets executed the memory only goes down to ~72,000K. If I continue the loop and watch memory it'll fluctuate between these two numbers.<p>
Is there another way to free the memory? Does anyone else find this behavior strange? I must be missing something, perhaps some monks can enlighten me.<p>
Thanks.
<code>
use strict;
use warnings;
print $$;
my @array;
my $i = 0;
while (1) {
$array[$i++]= '1234567890';
if ($i == 1_000_000) {
undef(@array); #BREAKPOINT HERE
$i = 0;
}
}
</code>
<b>UPDATE</b><br>
The memory is even kept after the array goes out of scope.
<code>
use strict;
use warnings;
print "PID: $$\n";
{
my @array;
my $i = 0;
while ($i <= 1_000_000) {
$array[$i++]= '1234567890';# for([0..1_000_000]);
if ($i == 1_000_000) {
undef(@array);
}
}
}
print "END\n"; # BREAKPOINT HERE, MEMORY IS STILL NOT FREE
</code>