From: thomas dot koenig at web-eci dot com
Operating system: Debian Wheezy x64
PHP version: 5.4.20
Package: opcache
Bug Type: Bug
Bug description:Memory leak with opCache, XML and continue
Description:
------------
Hello, everybody.
I noticed a problem while parsing XML with interlocked foreach loops : if I
write 'continue 2' to continue the upper loop, this will consume virtual
memory
far faster than with a single 'continue' or 'break'.
In my exemple, I parse a small basic XML; when I use 'continue 2', I see
that as
much as 8MB are used for this tiny loop. (See actual result)
On the other hand, only around 256kB are used if I replace this 'continue
2'
with 'break 2' (See expected result).
As you can see, this 'continue 2' leads the script to retain much more
memory
than needed, and that this virtual memory is retained even if the loops
allocating this memory are finished. Furthermore, we used the 'continue 2'
version on a server when parsing a 37MB XML file, and this leaded the
script to
fail because the OS prevented it to claim more than 2GB of virtual memory;
as
you can see, this isn't only a theoritical issue.
Awaiting a bugfix,
Regards.
Test script:
---------------
function testOpCache(){
$tab1 = array(1, 2, 3, 4, 5, 6, 7, 8, 9, 10);
$tab2 = array('a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j');
$tab3 = array(1 => 'a', 2 => 'b', 3 => 'c', 4 => 'd', 5 => 'e', 6 => 'f',
7 => 'g', 8 => 'h', 9 => 'i', 10 => 'j');
$xml = "
<level1>
<level2>info1</level2>
<level2>info2</level2>
<level2>info3</level2>
<level2>info4</level2>
<level2>info5</level2>
<level2>
<level3>subinfo1</level3>
<level3>subinfo2</level3>
<level3>subinfo3</level3>
<level3>subinfo4</level3>
<level3>
<level4>subsubinfo1</level4>
<level4>subsubinfo2</level4>
<level4>subsubinfo3</level4>
<level4>subsubinfo4</level4>
</level3>
<level3>
<level4>subsubinfo1</level4>
<level4>subsubinfo2</level4>
<level4>subsubinfo3</level4>
<level4>subsubinfo4</level4>
</level3>
<level3>
<level4>
<level5>aaa</level5>
<level5>aaa</level5>
<level5>aaa</level5>
<level5>aaa</level5>
<level5>aaa</level5>
</level4>
<level4>subsubinfo2</level4>
<level4>
<level5>aaa</level5>
<level5>aaa</level5>
<level5>aaa</level5>
<level5>aaa</level5>
<level5>aaa</level5>
</level4>
<level4>subsubinfo4</level4>
</level3>
</level2>
<level2>
<level3>subinfo1</level3>
<level3>subinfo2</level3>
<level3>subinfo3</level3>
<level3>subinfo4</level3>
<level3>
<level4>subsubinfo1</level4>
<level4>subsubinfo2</level4>
<level4>subsubinfo3</level4>
<level4>subsubinfo4</level4>
</level3>
<level3>
<level4>subsubinfo1</level4>
<level4>subsubinfo2</level4>
<level4>subsubinfo3</level4>
<level4>subsubinfo4</level4>
</level3>
<level3>
<level4>
<level5>aaa</level5>
<level5>aaa</level5>
<level5>aaa</level5>
<level5>aaa</level5>
<level5>aaa</level5>
</level4>
<level4>subsubinfo2</level4>
<level4>subsubinfo3</level4>
<level4>
<level5>aaa</level5>
<level5>aaa</level5>
<level5>aaa</level5>
<level5>aaa</level5>
<level5>aaa</level5>
</level4>
</level3>
</level2>
</level1>
";
$dom = simplexml_load_string($xml);
$tab4 = array();
sm();
foreach($tab1 as $t1){
foreach($tab2 as $t2){
foreach($tab3 as $t3){
foreach($dom->xpath('/level1/level2') as $level2){
foreach($level2->xpath('level3') as $level3){
foreach($level3->xpath('level4') as $level4){
foreach($level4->xpath('level5') as $level5){
continue 2;
//break 2;
}
}
}
}
}
}
}
sm();
}
function sm(){
echo memory_get_usage()."\n";
}
testOpCache();
Expected result:
----------------
thomas@Koenig:~$ php /home/thomas/Desktop/tests/opcache-1.php
239224
240120
thomas@Koenig:~$
Actual result:
--------------
thomas@Koenig:~$ php /home/thomas/Desktop/tests/opcache-1.php
239200
8416616
thomas@Koenig:~$
--
Edit bug report at https://bugs.php.net/bug.php?id=65743&edit=1
--
Try a snapshot (PHP 5.4):
https://bugs.php.net/fix.php?id=65743&r=trysnapshot54
Try a snapshot (PHP 5.3):
https://bugs.php.net/fix.php?id=65743&r=trysnapshot53
Try a snapshot (trunk):
https://bugs.php.net/fix.php?id=65743&r=trysnapshottrunk
Fixed in SVN: https://bugs.php.net/fix.php?id=65743&r=fixed
Fixed in release: https://bugs.php.net/fix.php?id=65743&r=alreadyfixed
Need backtrace: https://bugs.php.net/fix.php?id=65743&r=needtrace
Need Reproduce Script: https://bugs.php.net/fix.php?id=65743&r=needscript
Try newer version: https://bugs.php.net/fix.php?id=65743&r=oldversion
Not developer issue: https://bugs.php.net/fix.php?id=65743&r=support
Expected behavior: https://bugs.php.net/fix.php?id=65743&r=notwrong
Not enough info:
https://bugs.php.net/fix.php?id=65743&r=notenoughinfo
Submitted twice:
https://bugs.php.net/fix.php?id=65743&r=submittedtwice
register_globals: https://bugs.php.net/fix.php?id=65743&r=globals
PHP 4 support discontinued: https://bugs.php.net/fix.php?id=65743&r=php4
Daylight Savings: https://bugs.php.net/fix.php?id=65743&r=dst
IIS Stability: https://bugs.php.net/fix.php?id=65743&r=isapi
Install GNU Sed: https://bugs.php.net/fix.php?id=65743&r=gnused
Floating point limitations: https://bugs.php.net/fix.php?id=65743&r=float
No Zend Extensions: https://bugs.php.net/fix.php?id=65743&r=nozend
MySQL Configuration Error: https://bugs.php.net/fix.php?id=65743&r=mysqlcfg
