ID: 50111
Updated by: j...@php.net
-Summary: memory not properly freed when stream_context_create
is used
Reported By: datib...@php.net
-Status: Open
+Status: Wont fix
Bug Type: Streams related
Operating System: Linux
PHP Version: 5.2.11
New Comment:
PHP 5.3 has better garbage collection, hence this works there and not
in 5.2, wont fix for 5.2.
Previous Comments:
------------------------------------------------------------------------
[2009-11-19 15:28:07] datib...@php.net
My results for PHP 5.1.x were wrong, because I didn't compile them with
--enable-memory-limit, so the ini_set() wasn't actually working for
those; guess it was automatically added in 5.2.x even in the presence of
--disable-all ... my bad =(
After some more research on the PHP code itself, the problem seems to
lie in the fact that the following two functions are called by
stream_context_create():
zend_list_insert() - called by php_stream_context_alloc()
zend_list_addref() - called by php_stream_context_to_zval()
This results in a refcount of 2 for each context returned. This has
changed in 5.3.x but not sure in how many places ;-)
------------------------------------------------------------------------
[2009-11-19 13:39:45] datib...@php.net
I'm not trying to disable memory_limit. Setting it to "0" just happens
to make the issue appear faster.
Changing it to the below value of 1k yields the same results as
mentioned earlier, tested on the same 5 php configurations:
ini_set("memory_limit", "1000");
------------------------------------------------------------------------
[2009-11-19 09:38:42] j...@php.net
To disable memory_limit, you need to set it to -1, not 0.
------------------------------------------------------------------------
[2009-11-18 22:03:03] datib...@php.net
<?php
echo "This is PHP ", phpversion(),PHP_EOL;
ini_set("memory_limit", "0");
for ($i=0;$i<2000;++$i) {
$x = stream_context_create(array());
unset($x);
}
echo "Done", PHP_EOL;
?>
----------------
$ /usr/local/php-5.1.0/bin/php lala.php
This is PHP 5.1.0
Done
----------------
$ /usr/local/php-5.1.1/bin/php lala.php
This is PHP 5.1.1
Done
----------------
$ /usr/local/php-5.1.2/bin/php lala.php
This is PHP 5.1.2
Done
----------------
$ /usr/local/php-5.2.9/bin/php lala.php
This is PHP 5.2.9
Fatal error: Allowed memory size of 262144 bytes exhausted at
/usr/local/src/php-5.2.9/Zend/zend_list.c:47 (tried to allocate 12
bytes) in /home/tjerk/lala.php on line 7
----------------
$ /usr/local/php-5.2.11/bin/php lala.php
This is PHP 5.2.11
Fatal error: Allowed memory size of 262144 bytes exhausted at
/usr/local/src/php-5.2.11/main/streams/streams.c:1945 (tried to allocate
16 bytes) in /home/tjerk/lala.php on line 7
----------------
$ /usr/local/php-5.3/bin/php lala.php
This is PHP 5.3.0RC3-dev
Done
------------------------------------------------------------------------
[2009-11-18 18:14:02] j...@php.net
What code? There is no such script in this report that crashes. Not
even when changed to loop thousands of times. Not with PHP_5_2 or
PHP_5_3 or HEAD branches. So please, come up with a proper reproducing
script.
------------------------------------------------------------------------
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/50111
--
Edit this bug report at http://bugs.php.net/?id=50111&edit=1
