From: herkimer112 at yahoo dot dk
Operating system: WinXP
PHP version: 5.2.6
PHP Bug Type: Performance problem
Bug description: Large memory leak when creating tree-like data structures
Description:
------------
When creating tree-like data structures, where each member
is a node with a parent and children[] member,
the memory is not released when the tree is overwritten.
Example:
rootNode has children node1 and node2
node1 and node2 have parent rootNode
Reproduce code:
---------------
class myNode_class {
public $myChildren = array();
public $myParent = null;
function &addChild(&$node,$key) {
$this->myChildren[$key] = $node;
$node->myParent = $this;
}
}
function buildTree() {
$tree = new myNode_class($treeName);
for ($i=1;$i<100;$i++) {
$tree->addChild(new myNode_class(),$i);
}
}
function memleaktest() {
for ($j=1;$j<=10;$j++) {
buildTree();
echo 'Memory usage iteration '.$j.' '.memory_get_usage()."<br>";
}
}
memleaktest();
Expected result:
----------------
Memory usage iteration 1 97824
Memory usage iteration 2 97824
Memory usage iteration 3 97824
etc.
Actual result:
--------------
Memory usage iteration 1 97824
Memory usage iteration 2 128056
Memory usage iteration 3 158208
Memory usage iteration 4 188360
Memory usage iteration 5 218512
Memory usage iteration 6 248664
Memory usage iteration 7 278816
Memory usage iteration 8 308968
Memory usage iteration 9 339120
Memory usage iteration 10 369272
--
Edit bug report at http://bugs.php.net/?id=45520&edit=1
--
Try a CVS snapshot (PHP 5.2):
http://bugs.php.net/fix.php?id=45520&r=trysnapshot52
Try a CVS snapshot (PHP 5.3):
http://bugs.php.net/fix.php?id=45520&r=trysnapshot53
Try a CVS snapshot (PHP 6.0):
http://bugs.php.net/fix.php?id=45520&r=trysnapshot60
Fixed in CVS: http://bugs.php.net/fix.php?id=45520&r=fixedcvs
Fixed in release:
http://bugs.php.net/fix.php?id=45520&r=alreadyfixed
Need backtrace: http://bugs.php.net/fix.php?id=45520&r=needtrace
Need Reproduce Script: http://bugs.php.net/fix.php?id=45520&r=needscript
Try newer version: http://bugs.php.net/fix.php?id=45520&r=oldversion
Not developer issue: http://bugs.php.net/fix.php?id=45520&r=support
Expected behavior: http://bugs.php.net/fix.php?id=45520&r=notwrong
Not enough info:
http://bugs.php.net/fix.php?id=45520&r=notenoughinfo
Submitted twice:
http://bugs.php.net/fix.php?id=45520&r=submittedtwice
register_globals: http://bugs.php.net/fix.php?id=45520&r=globals
PHP 4 support discontinued: http://bugs.php.net/fix.php?id=45520&r=php4
Daylight Savings: http://bugs.php.net/fix.php?id=45520&r=dst
IIS Stability: http://bugs.php.net/fix.php?id=45520&r=isapi
Install GNU Sed: http://bugs.php.net/fix.php?id=45520&r=gnused
Floating point limitations: http://bugs.php.net/fix.php?id=45520&r=float
No Zend Extensions: http://bugs.php.net/fix.php?id=45520&r=nozend
MySQL Configuration Error: http://bugs.php.net/fix.php?id=45520&r=mysqlcfg
