From: jimmycnw at gmail dot com
Operating system: Linux
PHP version: 5.2.6
PHP Bug Type: Performance problem
Bug description: Memory leak in unserialize of nested arrays
Description:
------------
The code is attached. Try executing 'SAVING' first. It will create a file
'temp.txt' approximately 450Kb in size. Then execute 'LOADING'. You will
see, that over 3.5Mb (!!) of memory used in unserialize() function, while
there are just 450Kb of data.
Is it a bug in PHP? Any suggestions on how to fix it?
(When I do the same with string, not array, everything works fine. The
problem appears only when I use nested arrays)
Reproduce code:
---------------
define ('FILENAME', 'temp.txt');
define ('SIZE', 10 * 1024);
// SAVING
$array = array ();
for ($i = 0; $i<SIZE; $i++)
$array[] = array (uniqid ($i) => array ());
$data = serialize ($array);
file_put_contents (FILENAME, $data);
// LOADING
$before = memory_get_usage ();
$array = unserialize (file_get_contents (FILENAME));
$after = memory_get_usage ();
echo 'Memory used: '.($after-$before).' bytes, while size of data:
'.strlen (serialize ($array));
Expected result:
----------------
Memory used should be around 450Kb, while I see 3.5Mb.
Actual result:
--------------
Memory used: 3.5Mb
--
Edit bug report at http://bugs.php.net/?id=46018&edit=1
--
Try a CVS snapshot (PHP 5.2):
http://bugs.php.net/fix.php?id=46018&r=trysnapshot52
Try a CVS snapshot (PHP 5.3):
http://bugs.php.net/fix.php?id=46018&r=trysnapshot53
Try a CVS snapshot (PHP 6.0):
http://bugs.php.net/fix.php?id=46018&r=trysnapshot60
Fixed in CVS: http://bugs.php.net/fix.php?id=46018&r=fixedcvs
Fixed in release:
http://bugs.php.net/fix.php?id=46018&r=alreadyfixed
Need backtrace: http://bugs.php.net/fix.php?id=46018&r=needtrace
Need Reproduce Script: http://bugs.php.net/fix.php?id=46018&r=needscript
Try newer version: http://bugs.php.net/fix.php?id=46018&r=oldversion
Not developer issue: http://bugs.php.net/fix.php?id=46018&r=support
Expected behavior: http://bugs.php.net/fix.php?id=46018&r=notwrong
Not enough info:
http://bugs.php.net/fix.php?id=46018&r=notenoughinfo
Submitted twice:
http://bugs.php.net/fix.php?id=46018&r=submittedtwice
register_globals: http://bugs.php.net/fix.php?id=46018&r=globals
PHP 4 support discontinued: http://bugs.php.net/fix.php?id=46018&r=php4
Daylight Savings: http://bugs.php.net/fix.php?id=46018&r=dst
IIS Stability: http://bugs.php.net/fix.php?id=46018&r=isapi
Install GNU Sed: http://bugs.php.net/fix.php?id=46018&r=gnused
Floating point limitations: http://bugs.php.net/fix.php?id=46018&r=float
No Zend Extensions: http://bugs.php.net/fix.php?id=46018&r=nozend
MySQL Configuration Error: http://bugs.php.net/fix.php?id=46018&r=mysqlcfg
