[Maintain-dev] [Fwd: [PEAR-BUG] Bug #6247 [Opn->Csd]: DB_DataObjects not freeing memory after running through all records]

[Frederic Wenzel]

Dear fellow devs,

fyi: The bug I filed about the memory leak in DB_DataObject was now
fixed in CVS. Maybe we get a working release soon and can update, then.

I would appreciate if this happened pretty quickly (I will ask them for
it later) as IMHO this is a major bugfix that deserves a new beta release.

Merry Christmas!
Fred



-------- Original-Nachricht --------
Betreff: [PEAR-BUG] Bug #6247 [Opn->Csd]: DB_DataObjects not freeing
memory after running through all records
Datum: 22 Dec 2005 03:12:47 -0000
Von: PEAR Bug Database <pear-qa at lists.php.net>
An: fred at osuosl.org

ATTENTION! Do NOT reply to this email!
To reply, use the web interface found at
http://pear.php.net/bugs/bug.php?id=6247&edit=2


 ID:               6247
 Updated by:       alan_k at php.net
 Reported By:      fred at osuosl dot org
-Status:           Open
+Status:           Closed
 Id:               6247
 Type:             Bug
 Package:          DB_DataObject
 Operating System: Linux
 PHP Version:      4.4.0
 New Comment:

This bug has been fixed in CVS.

If this was a documentation problem, the fix will appear on
pear.php.net by the end of next Sunday (CET).

If this was a problem with the pear.php.net website, the change should
be live shortly.

Otherwise, the fix will appear in the package's next release.

Thank you for the report and for helping us make PEAR better.

I think this is due to the resultfields array - it is now cleared after
the last fetch.


Previous Comments:
------------------------------------------------------------------------

[2005-12-17 14:45:00] fred at osuosl dot org

Okay the 3.5 megs memory usage left are probably part of the framework
around the DataObjects, so that's okay for me.

In fact, memory usage does not increase significantly anymore
throughout the script if the free() calls are made.

And you are right, this issue should be resolved in order to reach
production status. If you have to fear to break your whole script
everytime you want to use a DB_DataObject, you will probably use a
different DB abstraction layer that does not have this problem.

Especially because the manual says there was no such problem.

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

[2005-12-17 13:05:36] contact at mann dot fr

I also had the same problem with a version of DB_DataObject that was
over a year old.  This bug has been around for awhile, but not really
detected.  I remember once someone passing the buck and saying that
Date took a lot of ressources, but it seems as if the liberation issue
is an important one.

If the text in the link is correct, after resolving this issue, the
person still had 3.5 megs used after his workaround.  Is this due to
considerations in the script or other things that could make
DB_DataObject bloated ?

The importance of resolving this issue seems to be the ability to use
DB_DataObject beyond prototypes and in heavy-demand applications.

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

[2005-12-17 12:45:06] contact at mann dot fr

Me too!
But I'm on PHP 5.
I use many different objects in one test script and it is a nightmare.
I'm over 10 Megs in memory for a script.

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

[2005-12-14 18:32:30] fred at osuosl dot org

Description:
------------
DB_DataObject 1.7.15 does not free the memory used for caching records
after traversing all the records in a query.

Even though the man page of free() states that after going through all
of the records it should set free the cache, free() has to be called
manually in order not to heavily leak memory.

If you do not free() manually, it keeps piling up memory usage until it
runs into PHP's memory limit.

Test script:
---------------
while (something) {
  $dbdo + DB_DataObject::Factory('foo");
  $dbdo->find();
  while ($dbdo->fetch()) {
    do_something();
  }
  // $dbdo->free();    // this fixes it.
  echo memory_get_usage()."\n";
}

See http://en.magenson.de/2005/12/14/db_dataobjects-memory-issues/ for
an example.


Expected result:
----------------
Memory usage of a couple of kilobytes, staying almost the same
throughout each while loop (because cached records should be freed
after traversal of all of them).

Actual result:
--------------
An increasing number of memory usage for each loop until the script
finally runs into php's memory limit.

Can be fixed by using the free() command at the indicated place.
However it should do that automatically.

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