Bug #53031 [Opn->Bgs]: GC does not collect before PHP issue "Allowed memory size exhausted"

[johannes]

Edit report at http://bugs.php.net/bug.php?id=53031&edit=1

 ID:                 53031
 Updated by:         johan...@php.net
 Reported by:        an0nym at narod dot ru
 Summary:            GC does not collect before PHP issue "Allowed memory
                     size exhausted"
-Status:             Open
+Status:             Bogus
 Type:               Bug
 Package:            *General Issues
 Operating System:   Windows Server 2008 R2 x64
 PHP Version:        5.3.3
 Block user comment: N

 New Comment:

Thank you for taking the time to write to us, but this is not
a bug. Please double-check the documentation available at
http://www.php.net/manual/ and the instructions on how to report
a bug at http://bugs.php.net/how-to-report.php

Check the documentation which describes when cycles are collected:
http://de3.php.net/manual/en/features.gc.collecting-cycles.php This
won't change.


Previous Comments:
------------------------------------------------------------------------
[2010-10-09 16:50:04] an0nym at narod dot ru

Description:
------------
GC does not collect cycles before PHP issue "Allowed memory size
exhausted", 

therefore it is possible for a script to get this error even if GC is
enabled and 

there is enough memory to reuse. 



To get error the script just has to fill all the remaining memory after
last GC 

and before next, fill no matter how: with garbage or normal info. 



It is obvious for me, that calling GC before issuing error is a must
have, as a 

last possibility to continue normal execution. 

Test script:
---------------
<?php

set_time_limit(0);

error_reporting(PHP_INT_MAX);

ini_set("memory_limit", "2M");



echo memory_get_peak_usage(true), "\r\n";



$o1 = new StdClass();

$o2 = new StdClass();

$o1->v1 = $o2;

$o1->v2 = $o1;

$o1->v = str_repeat("a", 1024 * 1024);

unset($o1, $o2);

echo memory_get_peak_usage(true), "\r\n";



$o1 = new StdClass();

$o2 = new StdClass();

$o1->v1 = $o2;

$o1->v2 = $o1;

$o1->v = str_repeat("a", 1024 * 1024);

unset($o1, $o2);

echo memory_get_peak_usage(true), "\r\n";

Expected result:
----------------
I expect to see the same result as if I run 



<?php

...

echo memory_get_peak_usage(true), "\r\n";



$o1 = new StdClass();

$o2 = new StdClass();

$o1->v1 = $o2;

$o1->v2 = $o1;

gc_collect_cycles();

$o1->v = str_repeat("a", 1024 * 1024);

unset($o1, $o2);

echo memory_get_peak_usage(true), "\r\n";

Actual result:
--------------
PHP Fatal error:  Allowed memory size of * bytes exhausted (tried to
allocate * 

bytes)


------------------------------------------------------------------------



-- 
Edit this bug report at http://bugs.php.net/bug.php?id=53031&edit=1