#48643 [Opn]: String functions memory issue (was:Memory not freed with FilterIterator)

ID: 48643 User updated by: zoe@php.net -Summary: Memory not freed with FilterIterator Reported By: zoe@php.net Status: Open -Bug Type: SPL related +Bug Type: Scripting Engine problem Operating System: Linux (Ubuntu) PHP Version: 5.2CVS-2009-06-22 (CVS) New Comment: Here are the files that changed between those dates (I have taken out things that look irrelevant like test files) RCS file: /repository/ZendEngine2/zend_builtin_functions.c,v date: 2008/06/25 22:37:14; author: felipe; state: Exp; lines: +2 -2 date: 2008/06/25 22:35:31; author: felipe; state: Exp; lines: +1 -2 RCS file: /repository/php-src/ext/reflection/php_reflection.c,v date: 2008/06/25 12:34:14; author: dmitry; state: Exp; lines: +152 -2 date: 2008/06/25 12:33:46; author: dmitry; state: Exp; lines: +128 -2 RCS file: /repository/php-src/ext/standard/formatted_print.c,v date: 2008/06/25 10:16:52; author: davidc; state: Exp; lines: +21 -25 date: 2008/06/25 08:56:42; author: davidc; state: Exp; lines: +12 -4 RCS file: /repository/php-src/ext/standard/string.c,v date: 2008/06/25 12:16:16; author: ohill; state: Exp; lines: +251 -328 RCS file: /repository/php-src/main/main.c,v date: 2008/06/25 12:18:51; author: dmitry; state: Exp; lines: +3 -1 date: 2008/06/25 12:18:21; author: dmitry; state: Exp; lines: +3 -1 date: 2008/06/25 12:18:36; author: dmitry; state: Exp; lines: +3 -1 RCS file: /repository/php-src/main/php_ticks.c,v date: 2008/06/25 12:18:51; author: dmitry; state: Exp; lines: +6 -1 date: 2008/06/25 12:18:22; author: dmitry; state: Exp; lines: +6 -1 date: 2008/06/25 12:18:36; author: dmitry; state: Exp; lines: +6 -1 RCS file: /repository/php-src/main/php_ticks.h,v date: 2008/06/25 12:18:51; author: dmitry; state: Exp; lines: +2 -1 date: 2008/06/25 12:18:22; author: dmitry; state: Exp; lines: +2 -1 The most likely candidates seem to be string.c and builtin_functions and it looks as though it is changes to parameter parsing that cause the problem. At this point I think we have done as much as we can to narrow this down. I'm changing this to Scripting engine as it clearly isn't an SPL issue. Previous Comments: ------------------------------------------------------------------------ [2009-06-23 15:39:27] zoe@php.net A checkout of PHP53 from the 25th June 2008 does *not* have the problem A checkout of PHP53 from the 26th June 2008 *does* have the problem ------------------------------------------------------------------------ [2009-06-23 14:13:37] robin_fernandes at uk dot ibm dot com Testcase below shows that the issue relates to an implicit cast to string on an SplFileInfo object when retrieved from a RecursiveDirectoryIterator during iteration. <?php $rdi = new RecursiveDirectoryIterator('/manyFiles'); echo "SplFileInfo explicit cast to string: "; foreach ($rdi as $v) { strlen((string)$v); } //OK echo memory_get_usage(true) . PHP_EOL; echo "SplFileInfo implicit cast to string: "; foreach ($rdi as $v) { strlen($v); } //Leaky echo memory_get_usage(true) . PHP_EOL; ?> php52: SplFileInfo explicit cast to string: 262144 SplFileInfo implicit cast to string: 262144 php53: SplFileInfo explicit cast to string: 524288 SplFileInfo implicit cast to string: 6291456 ------------------------------------------------------------------------ [2009-06-23 13:02:34] zoe@php.net Looking backwards through PHP builds I have currently narrowed this down to a change that went in to PHP 5.3 somewhere between the 12th June 2008 and the 1st July 2008. ------------------------------------------------------------------------ [2009-06-23 12:13:49] robin_fernandes at uk dot ibm dot com Below is a simplified testcase which I think exposes the same leak. '/manyFiles' is a directory containing 10000 files. <?php $rii = new RecursiveIteratorIterator( new RecursiveDirectoryIterator('/manyFiles') ); function noop() {} echo "noop call in loop (no leak) : "; foreach ($rii as $v) { noop($v); } echo memory_get_usage() . PHP_EOL; echo "strlen call in loop (leak on 53) : "; foreach ($rii as $v) { strlen($v); } echo memory_get_usage() . PHP_EOL; ?> Output on php52: noop call in loop (no leak) : 66176 strlen call in loop (leak on 53) : 66176 Output on php53: noop call in loop (no leak) : 337448 strlen call in loop (leak on 53) : 6028496 ------------------------------------------------------------------------ [2009-06-22 14:33:05] zoe@php.net I tested with PHP 5.2 but do not see the same issue. I believe this is specific to PHP 5.3. ------------------------------------------------------------------------ The remainder of the comments for this report are too long. To view the rest of the comments, please view the bug report online at http://bugs.php.net/48643 -- Edit this bug report at http://bugs.php.net/?id=48643&edit=1