Glad you got an speedy explanation. It seems so obvious once it is pointed out, but then no one else here spotted the cause either:(

It very non-intuative that the rates of memory growth you were seeing could be attributed to the simple act of stringifying previously numeric values. Once you know what to look for, it is easy to see the how quickly the memory usage grows when ths happens.

A (minimum) of 70% growth for integers: 

c:\Perl\test>p1
[0] Perl> use Devel::Size qw[ total_size ];;
[0] Perl> @a = (0) x 1e6;;
[0] Perl> print total_size( \@a );;
20000056
[0] Perl> $_.='' for @a;;
[0] Perl> print total_size( \@a );;
34000056

[download]

And a whopping 300% for floats. 

c:\Perl\test>p1
[0] Perl> use Devel::Size qw[ total_size ];;
[0] Perl> @a = ( 1.0 ) x 1e6;;
[0] Perl> print total_size( \@a );;
24000056
[0] Perl> $_.='' for @a;;
[0] Perl> print total_size( \@a );;
75000056

[download]

Definitely one to remember if you are running close to the memory limits of your machine.

Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
Lingua non convalesco, consenesco et abolesco. -- Rule 1 has a caveat! -- Who broke the cabal?
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.

In reply to Re^2: Memory Error Printing Multiple Hashes Simultaneously by BrowserUk
in thread Memory Error Printing Multiple Hashes Simultaneously by bernanke01

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.