Re: OUT OF MEMORY!

[reyjrar]

I've experienced out of memory problems when code I've written has gotten stuck in loops inifinitely or when I accidentally pushed the contents of the same array onto itself multiple times.

A few issues I have with this code. You can't ultimately guarantee the size of any of these files, so its best to not read them all in at the same time, you can process the file chunk by chunk using the scalar <> or the read() or even sysopen,sysread if you want to get complicated. instead of:

open(FILE, "<file.txt");
my @thing = <FILE>;
close FILE;
for(@thing) {
    if(/this/) {
        push @other,$_;
    }
    elsif(/that/) {
        push @another,$_;
    }
    else {
        push @crap,$_;
    }
}

try:

open(FILE, "<file.txt");
while(local $_ = <FILE>) {
    if(/this/) {
        push @other,$_;
    }
    elsif(/that/) {
        push @another,$_;
    }
    else {
        push @stuff,$_;
    }
}
close FILE;

Another thing that bothers me about this code is that you're not cleaning everything up and you have multiple instances of those files in memory at any given time. This could be adding up.. in the @filenames lets say it takes up 128kb, then you join it together on $filename without destoroying the array, you've used 256kb. if you want to operate on the scalar, then you might want to undef the array @filenames=(); to save some memory. Also, if you're just gonna join things anyways, why not use the str concatenation operator like so:

open(FILE,"<file.txt");
my $template = '';
while(my $line = <FILE>) {
    $template .= $line;
}
close FILE;

which I believe can be shortened even more into:

my $template = '';
open(FILE, "<file.txt") && while($template .= <FILE>) {};
close FILE;
die "bad stuff happened" unless length $template;

anyways, play with it somemore. and use offline mode to do some debugging and but 'print' statements all over your loops, Your data set may contain something you haven't thought of and it sounds to me like the program is looping infinitely because of it.

anyways, good luck with it, and let us know how it turns out.


-brad..

[Hofmator]

Just a small comment on reading in a whole file at once. It's not efficient to read in linewise just to glue them together afterwards. Instead do it like this:

my $template;
{
  local $/; # undef $/ => file slurp mode
  open (FILE, '<', 'file.txt') or die "Couldn't open file.txt: $!";
  $template = <FILE>;
  close FILE;
}

-- Hofmator