#22435 [NEW]: count() is slow when used with large arrays

[carl at topthetable dot com]

From:             carl at topthetable dot com
Operating system: Redhat 7.2
PHP version:      4.3.1
PHP Bug Type:     Performance problem
Bug description:  count() is slow when used with large arrays

count() is increasingly slow when used to count large arrays.  This is
using 4.3.1 (compiled from source) on a Redhat 7.2 box.  The box has about
80Mb free, so it's not a paging issue.  It works as expected on Mac OS X
running 4.3.1-dev.

Looking at PHP's and Zend's source, I would expect the time taken to
return the count() of an array to be similar regardless of the size of the
array.

Below is a script to demonstrate the problem.  


<?
  $st = microtime();

  echo "Script started:            ".microtime()."\n";

  dosize( 10 );
  dosize( 20 );
  dosize( 50 );
  dosize( 100 );
  dosize( 200 );
  dosize( 500 );
  dosize( 1000 );
  dosize( 5000 );
  dosize( 10000 );

  function dosize( $y ) {

    echo "Doing size $y\n";

    echo "  Starting array building:".microtime()."\n";

    $t = array();
    for ( $i=0; $i<$y; $i++ ) {
      $t[] = array( array( "3", "1" ), "3", array( array ( "5", "1", "8" )
) );
    }

    echo "  Array built:            ".microtime()."\n";

    count( $t );

    echo "  Count finished:         ".microtime()."\n";
  }
?>
-- 
Edit bug report at http://bugs.php.net/?id=22435&edit=1
-- 
Try a CVS snapshot:         http://bugs.php.net/fix.php?id=22435&r=trysnapshot
Fixed in CVS:               http://bugs.php.net/fix.php?id=22435&r=fixedcvs
Fixed in release:           http://bugs.php.net/fix.php?id=22435&r=alreadyfixed
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Expected behavior:          http://bugs.php.net/fix.php?id=22435&r=notwrong
Not enough info:            http://bugs.php.net/fix.php?id=22435&r=notenoughinfo
Submitted twice:            http://bugs.php.net/fix.php?id=22435&r=submittedtwice
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PHP 3 support discontinued: http://bugs.php.net/fix.php?id=22435&r=php3
Daylight Savings:           http://bugs.php.net/fix.php?id=22435&r=dst
IIS Stability:              http://bugs.php.net/fix.php?id=22435&r=isapi
Install GNU Sed:            http://bugs.php.net/fix.php?id=22435&r=gnused