From:
Operating system: Ubuntu 10.04 LTS
PHP version: 5.3.2
Package: PDO related
Bug Type: Bug
Bug description:Memory leak when executing SQL "EXEC" statements
Description:
------------
On Linux, using PHP 5.3.2-1ubuntu4 with Suhosin-Patch (cli) and FreeTDS
0.82-6build1 (it's a vanilla lucid install, fully up to date):
When executing stored procedures using the "EXEC" SQL statement, both
PDOStatement->execute as well as PDO::query seem to have a memory leak. We
found this while executing a stored procedure within a loop: memory usage
just kept increasing till the memory limit was reached. Unsetting/nullyfing
variables does not help.
The leak is not present (memory usage stays perfectly constant) when using
a "SELECT" SQL statement (which returns the exact same results as the
stored procedure).
I have a feeling PDO is maybe only clearing the memory when it deals with a
"SELECT" statement, and it misses the fact that data can also come back
through "EXEC" statements?
This bug might be slightly related to bug 50755.
Test script:
---------------
// $polyItemArray is populated with a list of 300 IDs (integers).
// We loop through the array, and execute a stored procedure during each
iteration:
foreach( $polyItemArray as $polyItemKey => $polyItem) {
echo date('H:i:s') . ' | Processing: ' . $polyItem['sgp_id'];
$dbh->query('EXEC proc_map_get_sgp_polygons ' . $polyItem['sgp_id'],
PDO::FETCH_ASSOC);
/*
// Alternate way of calling the procedure using PDOStatement; same
leak is present:
$stmt = $dbh->prepare($sql);
$stmt->setFetchMode(PDO::FETCH_ASSOC);
$stmt->execute( array($polyItem['sgp_id']) );
$stmt->closeCursor();
unset($stmt);
*/
unset($polyItemKey);
unset($polyItem);
echo ' memory usage: ' . memory_get_usage(). ' bytes'. PHP_EOL;
}
// When running the script, memory usage just keeps increasing.
Expected result:
----------------
I would expect the memory usage of the script to stay constant.
Actual result:
--------------
Memory usage just keeps increasing.
--
Edit bug report at http://bugs.php.net/bug.php?id=51796&edit=1
--
Try a snapshot (PHP 5.2):
http://bugs.php.net/fix.php?id=51796&r=trysnapshot52
Try a snapshot (PHP 5.3):
http://bugs.php.net/fix.php?id=51796&r=trysnapshot53
Try a snapshot (PHP 6.0):
http://bugs.php.net/fix.php?id=51796&r=trysnapshot60
Fixed in SVN:
http://bugs.php.net/fix.php?id=51796&r=fixed
Fixed in SVN and need be documented:
http://bugs.php.net/fix.php?id=51796&r=needdocs
Fixed in release:
http://bugs.php.net/fix.php?id=51796&r=alreadyfixed
Need backtrace:
http://bugs.php.net/fix.php?id=51796&r=needtrace
Need Reproduce Script:
http://bugs.php.net/fix.php?id=51796&r=needscript
Try newer version:
http://bugs.php.net/fix.php?id=51796&r=oldversion
Not developer issue:
http://bugs.php.net/fix.php?id=51796&r=support
Expected behavior:
http://bugs.php.net/fix.php?id=51796&r=notwrong
Not enough info:
http://bugs.php.net/fix.php?id=51796&r=notenoughinfo
Submitted twice:
http://bugs.php.net/fix.php?id=51796&r=submittedtwice
register_globals:
http://bugs.php.net/fix.php?id=51796&r=globals
PHP 4 support discontinued: http://bugs.php.net/fix.php?id=51796&r=php4
Daylight Savings: http://bugs.php.net/fix.php?id=51796&r=dst
IIS Stability:
http://bugs.php.net/fix.php?id=51796&r=isapi
Install GNU Sed:
http://bugs.php.net/fix.php?id=51796&r=gnused
Floating point limitations:
http://bugs.php.net/fix.php?id=51796&r=float
No Zend Extensions:
http://bugs.php.net/fix.php?id=51796&r=nozend
MySQL Configuration Error:
http://bugs.php.net/fix.php?id=51796&r=mysqlcfg
