Bug #51523 [Opn]: Memory leak on fread()

[evilzluk at gmail dot com]

Edit report at http://bugs.php.net/bug.php?id=51523edit=1

 ID:   51523
 User updated by:  evilzluk at gmail dot com
 Reported by:  evilzluk at gmail dot com
 Summary:  Memory leak on fread()
 Status:   Open
 Type: Bug
 Package:  Performance problem
 Operating System: Linux
 PHP Version:  Irrelevant

 New Comment:

Description:



The problem is the fread() uses a normal amount of a memory. But there
are too many unallocated anonymous memory pages.

So if the file size 2G the script may cause eating up to 2G of RAM. But
the script's runtime memory is 5M.



The problem is occured even if:

$fp = fopen($file, rb);

while(!feof($fp))

fread($fp, 1024);

fclose($fp);



After that the memory isn't released so we have a garbadge in the
memory.





Test script:

---

?php



$file = A.very.big.file.avi;

ob_start();

$fp = fopen($file, rb);

if ($fp)

{

while(!feof($fp))

{

echo(fread($fp, 1024));

if (ob_get_length())

{

ob_flush();

flush();

ob_end_flush();

}

}

fclose($fp);

}

@ob_flush();

@flush();

@ob_end_flush();

@ob_end_clean();



?





Expected result:



The total amount of a memory usage should be at least php script
runtime memory usage + 1024 (+ some buffer (up to 8192)). But not
almost all the physical memory (0...unlimited)


Previous Comments:

[2010-04-10 01:06:50] evilzluk at gmail dot com

Description:

The problem is the fread() uses a normal amount of a memory. But there
are too many unallocated anonymous memory pages.

So if the file size 2G the script may cause eating up to 2G of RAM. But
the script's runtime memory is 5M.



The problem is occured even if:

$fp = fopen($file, rb);

while(!feof($fp))

fread($fp, 1024);

fclose($fp);



After that the memory isn't released so we have a garbadge in the
memory.



Test script:
---
?php



$file = A.very.big.file.avi;

ob_start();

$fp = fopen($file, wb);

if ($fp)

{

while(!feof($fp))

{

echo(fread($fp, 1024));

if (ob_get_length())

{

ob_flush();

flush();

ob_end_flush();

}

}

fclose($fp);



@ob_flush();

@flush();

@ob_end_flush();

@ob_end_clean();

}

?



Expected result:

The total amount of a memory usage should be at least php script
runtime memory usage + 1024 (+ some buffer (up to 8192)). But not
almost all the physical memory (0...unlimited)











-- 
Edit this bug report at http://bugs.php.net/bug.php?id=51523edit=1

Bug #51523 [Opn-Csd]: Memory leak on fread()

[evilzluk at gmail dot com]

Edit report at http://bugs.php.net/bug.php?id=51523edit=1

 ID:   51523
 User updated by:  evilzluk at gmail dot com
 Reported by:  evilzluk at gmail dot com
 Summary:  Memory leak on fread()
-Status:   Open
+Status:   Closed
 Type: Bug
 Package:  Performance problem
 Operating System: Linux
 PHP Version:  Irrelevant

 New Comment:

resolved adding to cronjob:

sync

echo 1  /proc/sys/vm/drop_caches

echo 2  /proc/sys/vm/drop_caches

echo 3  /proc/sys/vm/drop_caches

sync


Previous Comments:

[2010-04-10 17:05:17] evilzluk at gmail dot com

Description:



The problem is the fread() uses a normal amount of a memory. But there
are too many unallocated anonymous memory pages.

So if the file size 2G the script may cause eating up to 2G of RAM. But
the script's runtime memory is 5M.



The problem is occured even if:

$fp = fopen($file, rb);

while(!feof($fp))

fread($fp, 1024);

fclose($fp);



After that the memory isn't released so we have a garbadge in the
memory.





Test script:

---

?php



$file = A.very.big.file.avi;

ob_start();

$fp = fopen($file, rb);

if ($fp)

{

while(!feof($fp))

{

echo(fread($fp, 1024));

if (ob_get_length())

{

ob_flush();

flush();

ob_end_flush();

}

}

fclose($fp);

}

@ob_flush();

@flush();

@ob_end_flush();

@ob_end_clean();



?





Expected result:



The total amount of a memory usage should be at least php script
runtime memory usage + 1024 (+ some buffer (up to 8192)). But not
almost all the physical memory (0...unlimited)


[2010-04-10 01:06:50] evilzluk at gmail dot com

Description:

The problem is the fread() uses a normal amount of a memory. But there
are too many unallocated anonymous memory pages.

So if the file size 2G the script may cause eating up to 2G of RAM. But
the script's runtime memory is 5M.



The problem is occured even if:

$fp = fopen($file, rb);

while(!feof($fp))

fread($fp, 1024);

fclose($fp);



After that the memory isn't released so we have a garbadge in the
memory.



Test script:
---
?php



$file = A.very.big.file.avi;

ob_start();

$fp = fopen($file, wb);

if ($fp)

{

while(!feof($fp))

{

echo(fread($fp, 1024));

if (ob_get_length())

{

ob_flush();

flush();

ob_end_flush();

}

}

fclose($fp);



@ob_flush();

@flush();

@ob_end_flush();

@ob_end_clean();

}

?



Expected result:

The total amount of a memory usage should be at least php script
runtime memory usage + 1024 (+ some buffer (up to 8192)). But not
almost all the physical memory (0...unlimited)











-- 
Edit this bug report at http://bugs.php.net/bug.php?id=51523edit=1

[PHP-BUG] Bug #51523 [NEW]: Memory leak on fread()

[evilzluk at gmail dot com]

From: 
Operating system: Linux
PHP version:  Irrelevant
Package:  Performance problem
Bug Type: Bug
Bug description:Memory leak on fread()

Description:

The problem is the fread() uses a normal amount of a memory. But there are
too many unallocated anonymous memory pages.

So if the file size 2G the script may cause eating up to 2G of RAM. But
the script's runtime memory is 5M.



The problem is occured even if:

$fp = fopen($file, rb);

while(!feof($fp))

fread($fp, 1024);

fclose($fp);



After that the memory isn't released so we have a garbadge in the memory.



Test script:
---
?php



$file = A.very.big.file.avi;

ob_start();

$fp = fopen($file, wb);

if ($fp)

{

while(!feof($fp))

{

echo(fread($fp, 1024));

if (ob_get_length())

{

ob_flush();

flush();

ob_end_flush();

}

}

fclose($fp);



@ob_flush();

@flush();

@ob_end_flush();

@ob_end_clean();

}

?



Expected result:

The total amount of a memory usage should be at least php script runtime
memory usage + 1024 (+ some buffer (up to 8192)). But not almost all the
physical memory (0...unlimited)






-- 
Edit bug report at http://bugs.php.net/bug.php?id=51523edit=1
-- 
Try a snapshot (PHP 5.2):
http://bugs.php.net/fix.php?id=51523r=trysnapshot52
Try a snapshot (PHP 5.3):
http://bugs.php.net/fix.php?id=51523r=trysnapshot53
Try a snapshot (PHP 6.0):
http://bugs.php.net/fix.php?id=51523r=trysnapshot60
Fixed in SVN:
http://bugs.php.net/fix.php?id=51523r=fixed
Fixed in SVN and need be documented: 
http://bugs.php.net/fix.php?id=51523r=needdocs
Fixed in release:
http://bugs.php.net/fix.php?id=51523r=alreadyfixed
Need backtrace:  
http://bugs.php.net/fix.php?id=51523r=needtrace
Need Reproduce Script:   
http://bugs.php.net/fix.php?id=51523r=needscript
Try newer version:   
http://bugs.php.net/fix.php?id=51523r=oldversion
Not developer issue: 
http://bugs.php.net/fix.php?id=51523r=support
Expected behavior:   
http://bugs.php.net/fix.php?id=51523r=notwrong
Not enough info: 
http://bugs.php.net/fix.php?id=51523r=notenoughinfo
Submitted twice: 
http://bugs.php.net/fix.php?id=51523r=submittedtwice
register_globals:
http://bugs.php.net/fix.php?id=51523r=globals
PHP 4 support discontinued:  http://bugs.php.net/fix.php?id=51523r=php4
Daylight Savings:http://bugs.php.net/fix.php?id=51523r=dst
IIS Stability:   
http://bugs.php.net/fix.php?id=51523r=isapi
Install GNU Sed: 
http://bugs.php.net/fix.php?id=51523r=gnused
Floating point limitations:  
http://bugs.php.net/fix.php?id=51523r=float
No Zend Extensions:  
http://bugs.php.net/fix.php?id=51523r=nozend
MySQL Configuration Error:   
http://bugs.php.net/fix.php?id=51523r=mysqlcfg