I have a question about memory usage when saving large hashes to disk via Storable.pm's lock_store and lock_retrieve functions. This is kind of an extreme example:

If I have a hash that looks like this and I've managed to save it to a file called 'books.data' with lock_store: 

my $x = {
    'Moby Dick' => "The entire text of Moby Dick...",
    'The Lord of the Rings' => "The entire text of Lord of the Rings..
+.",
    'Great Expectations' => "The entire text of Great Expectations..."
+,
    'War and Peace' => "The entire text of War and Peace...",
};

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What happens when I do this: 
my $books = lock_retrieve('books.data');

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Am I reading all that data into memory at once? How hard is it on the machine if I iterate through the keys of $%books? 
my $search_string = 'ect';
foreach $title (keys %$books) {
    print $books->{$title} if $title =~ /$search_string/i;
}

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I'd appreciate any comments on this. I'm kind of wondering how much data is too much. Thanks for your help!

In reply to Saving Large Hashes to Disk via Storable.pm by kingman

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