From:             oliver at burtchen dot com
Operating system: 
PHP version:      5.0.2
PHP Bug Type:     Performance problem
Bug description:  array_key_exists() makes a copy of the given array

Description:
------------
it looks loke array_key_exists() makes a copy of the given array if there
is a reference to that array. if there is no reference, everything works
well.

Reproduce code:
---------------
// just to get the time in microseconds
function getmicrotime() {
   list($usec, $sec) = explode(" ",microtime());
   return ((float)$usec + (float)$sec);
}


$cnt = 2000;
$a = array_fill(0, $cnt, 'foo');


// this works as aspected very fast

$mtime = getmicrotime();

for ($i = 0; $cnt > $i; $i++)
        array_key_exists($i, $a);

echo getmicrotime() - $mtime . '<br>';


$b =& $a;  // making a reference, but not using it


// this will take a huge amount of time, but it's the same code as above

$mtime = getmicrotime();

for ($i = 0; $cnt > $i; $i++)
        array_key_exists($i, $a);

echo getmicrotime() - $mtime . '<br>';



Expected result:
----------------
the two loops should work the same.


-- 
Edit bug report at http://bugs.php.net/?id=30295&edit=1
-- 
Try a CVS snapshot (php4):   http://bugs.php.net/fix.php?id=30295&r=trysnapshot4
Try a CVS snapshot (php5.0): http://bugs.php.net/fix.php?id=30295&r=trysnapshot50
Try a CVS snapshot (php5.1): http://bugs.php.net/fix.php?id=30295&r=trysnapshot51
Fixed in CVS:                http://bugs.php.net/fix.php?id=30295&r=fixedcvs
Fixed in release:            http://bugs.php.net/fix.php?id=30295&r=alreadyfixed
Need backtrace:              http://bugs.php.net/fix.php?id=30295&r=needtrace
Need Reproduce Script:       http://bugs.php.net/fix.php?id=30295&r=needscript
Try newer version:           http://bugs.php.net/fix.php?id=30295&r=oldversion
Not developer issue:         http://bugs.php.net/fix.php?id=30295&r=support
Expected behavior:           http://bugs.php.net/fix.php?id=30295&r=notwrong
Not enough info:             http://bugs.php.net/fix.php?id=30295&r=notenoughinfo
Submitted twice:             http://bugs.php.net/fix.php?id=30295&r=submittedtwice
register_globals:            http://bugs.php.net/fix.php?id=30295&r=globals
PHP 3 support discontinued:  http://bugs.php.net/fix.php?id=30295&r=php3
Daylight Savings:            http://bugs.php.net/fix.php?id=30295&r=dst
IIS Stability:               http://bugs.php.net/fix.php?id=30295&r=isapi
Install GNU Sed:             http://bugs.php.net/fix.php?id=30295&r=gnused
Floating point limitations:  http://bugs.php.net/fix.php?id=30295&r=float
MySQL Configuration Error:   http://bugs.php.net/fix.php?id=30295&r=mysqlcfg

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