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Date: Mon, 05 Mar 2007 16:54:39 -0600
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To: Antony Dovgal <antony@zend.com>
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Subject: Re: [PHP-DEV] The way the engine works?
From: brianm@dealnews.com (Brian Moon)

Antony Dovgal wrote:
> Yup, the language stole ~32Kb of your memory and used it to speedup the 
> allocation of small chunks.

Ok, in my attempt to send a sane looking example, I cleaned up the problem.

<?php

$str = "This is a medium length string";

$start = memory_get_usage();
for($x=1;$x<=1000000;$x++){
      $var = $str." ".$x.": (3.5): ".time()."\n";
}
$first_growth = number_format(memory_get_usage() - $start);

$start = memory_get_usage();
for($x=1;$x<=1000000;$x++){
      $var = "$str $x: (3.5): ".time()."\n";
}
$growth = number_format(memory_get_usage() - $start);


echo "first growth: $first_growth\nsecond growth: $growth\n";

?>

The introduction of $x into the string makes the difference.

first growth: 892
second growth: 3,955,068

-- 

Brian Moon
-------------
http://dealnews.com/
It's good to be cheap =)