[PHP-BUG] Bug #52536 [NEW]: array_shift memory leak.
From:
Operating system: CentOS 5.3
PHP version: 5.3.3
Package: Performance problem
Bug Type: Bug
Bug description:array_shift memory leak.
Description:
array_shift is causing a memory leak when used.
Take the following code:
if (count($write->writeBuffer))
{
$data = array_shift($write->writeBuffer);
$written = fwrite($stream, $data);
if ($written !== FALSE)
{
if ($written < strlen($data))
{
array_unshift($write->writeBuffer, substr($data,
$written));
}
}
}
When running under as a daemon process, memory will continue to rise with
this
code.
However, simply changing the code to:
if (count($write->writeBuffer))
{
//print_r($write);
$data = reset($write->writeBuffer);
$key = key($write->writeBuffer);
//echo "writing data: $data\n";
$written = fwrite($stream, $data);
if ($written !== FALSE)
{
if ($written < strlen($data))
{
$write->writeBuffer[$key] = substr($data, $written);
} else
{
unset($write->writeBuffer[$key]);
}
}
}
Fixes the problem and no longer leaks and stays at a steady number.
Test script:
---
requires a long running process that repeatedly calls array_shift to
demonstrate
Expected result:
Memory to be freed that is used for the array_shift operation.
Actual result:
--
Memory is not freed upon use and contiously climbs in total memory
consumption by
the PHP process.
--
Edit bug report at http://bugs.php.net/bug.php?id=52536&edit=1
--
Try a snapshot (PHP 5.2):
http://bugs.php.net/fix.php?id=52536&r=trysnapshot52
Try a snapshot (PHP 5.3):
http://bugs.php.net/fix.php?id=52536&r=trysnapshot53
Try a snapshot (trunk):
http://bugs.php.net/fix.php?id=52536&r=trysnapshottrunk
Fixed in SVN:
http://bugs.php.net/fix.php?id=52536&r=fixed
Fixed in SVN and need be documented:
http://bugs.php.net/fix.php?id=52536&r=needdocs
Fixed in release:
http://bugs.php.net/fix.php?id=52536&r=alreadyfixed
Need backtrace:
http://bugs.php.net/fix.php?id=52536&r=needtrace
Need Reproduce Script:
http://bugs.php.net/fix.php?id=52536&r=needscript
Try newer version:
http://bugs.php.net/fix.php?id=52536&r=oldversion
Not developer issue:
http://bugs.php.net/fix.php?id=52536&r=support
Expected behavior:
http://bugs.php.net/fix.php?id=52536&r=notwrong
Not enough info:
http://bugs.php.net/fix.php?id=52536&r=notenoughinfo
Submitted twice:
http://bugs.php.net/fix.php?id=52536&r=submittedtwice
register_globals:
http://bugs.php.net/fix.php?id=52536&r=globals
PHP 4 support discontinued: http://bugs.php.net/fix.php?id=52536&r=php4
Daylight Savings:http://bugs.php.net/fix.php?id=52536&r=dst
IIS Stability:
http://bugs.php.net/fix.php?id=52536&r=isapi
Install GNU Sed:
http://bugs.php.net/fix.php?id=52536&r=gnused
Floating point limitations:
http://bugs.php.net/fix.php?id=52536&r=float
No Zend Extensions:
http://bugs.php.net/fix.php?id=52536&r=nozend
MySQL Configuration Error:
http://bugs.php.net/fix.php?id=52536&r=mysqlcfg
Bug #52536 [Opn->Csd]: array_shift memory leak.
Edit report at http://bugs.php.net/bug.php?id=52536&edit=1
ID: 52536
User updated by:aikar at aikar dot co
Reported by:aikar at aikar dot co
Summary:array_shift memory leak.
-Status: Open
+Status: Closed
Type: Bug
Package:Performance problem
Operating System: CentOS 5.3
PHP Version:5.3.3
Block user comment: N
New Comment:
Sorry, upon furthur review i noticed the memory does stop rising
eventually, and
found my memory "leak" to be a flaw somewhere else that took it up
high.
closing since this isnt a bug.
Previous Comments:
[2010-08-04 22:43:22] aikar at aikar dot co
Description:
array_shift is causing a memory leak when used.
Take the following code:
if (count($write->writeBuffer))
{
$data = array_shift($write->writeBuffer);
$written = fwrite($stream, $data);
if ($written !== FALSE)
{
if ($written < strlen($data))
{
array_unshift($write->writeBuffer, substr($data,
$written));
}
}
}
When running under as a daemon process, memory will continue to rise
with this
code.
However, simply changing the code to:
if (count($write->writeBuffer))
{
//print_r($write);
$data = reset($write->writeBuffer);
$key = key($write->writeBuffer);
//echo "writing data: $data\n";
$written = fwrite($stream, $data);
if ($written !== FALSE)
{
if ($written < strlen($data))
{
$write->writeBuffer[$key] = substr($data,
$written);
} else
{
unset($write->writeBuffer[$key]);
}
}
}
Fixes the problem and no longer leaks and stays at a steady number.
Test script:
---
requires a long running process that repeatedly calls array_shift to
demonstrate
Expected result:
Memory to be freed that is used for the array_shift operation.
Actual result:
--
Memory is not freed upon use and contiously climbs in total memory
consumption by
the PHP process.
--
Edit this bug report at http://bugs.php.net/bug.php?id=52536&edit=1
