From:
Operating system: vistax64
PHP version: 5.3.2
Package: MySQLi related
Bug Type: Bug
Bug description:Mysqli - zombie links
Description:
------------
Mysqli generated links appear to be persistent regardless of settings as
long as the PHP process (or Apache server process if PHP is loaded as a
module as in my case) is running. Any new connections just add to the
total link count, and neither closing or unsetting the link nor garbage
collection has any effect on removing them. Restarting mysqld has no
effect.
I'm using Vista x64, Apache 2.2, PHP5.3.2 as a module (thread-safe
download), and Mysql 5.1.45.
The below code produces no Mysql error, but after the second page reload,
PHP generates a 'Too many open links (1)' error from that point on until
the PHP server process is restarted. Mysql shows no connection attempts on
its end. No further db links can be established because of
mysqli.max_links being reached. The only way to solve this that I've found
so far is to set mysqli.max_links=-1 and just ignore the ever-growing
number of zombie links. Either that or restart the Apache server every few
seconds.
Also of note, no matter how high max_links is set and the script is ran,
get_connection_stats() will only show 1 active_connections, 0
active_persistent_connections, 0 connection_reused, 0 reconnect, 0
*_close.
Also, when using mysqli::real_connect method after mysqli_init(), it
establishes 1 active_persistent_connections according to
get_connection_stats() even though I have mysqli.allow_persistent=Off,
where as mysqli::__construct does not.
Test script:
---------------
php.ini...
mysqli.max_links = 1
mysqli.allow_persistent = Off
mysqli.max_persistent = 0
mysqli.reconnect = Off
my.ini...
max_connections=1
max_user_connections=1
connect_timeout=10
// just hit browser refresh once or twice
<?php
$mysqli = mysqli_init();
$mysqli->options(MYSQLI_OPT_CONNECT_TIMEOUT, 5);
$mysqli->real_connect($m_host, $m_user, $m_pass, $m_db);
echo $mysqli->error."<br>";
var_dump($mysqli->get_connection_stats());
mysqli_close($mysqli);
die("finished");
?>
Expected result:
----------------
The above code should never generate a PHP error. Link in PHP memory
should actually be deleted either on close() or on script end.
If this behavior is intended for another purpose, in order to free up
memory and available connection/link slots in PHP, can a function or
setting be added or tweaked to actually delete the link from memory either
on demand or after some user specified time limit, or automatically on
script end? Or is there another method of handling this already? Should
there be a mysql(i).connect_timeout setting in php.ini? Is
mysqli::real_connect disobeying mysqli.allow_persistent=Off?
Actual result:
--------------
[19-Apr-2010 12:56:58] PHP Warning: mysqli::mysqli(): Too many open links
(1) in D:\Server\Scripts\mysql_benchmarks.php on line 15
[19-Apr-2010 12:56:58] PHP Warning: main(): Couldn't fetch mysqli in
D:\Server\Scripts\mysql_benchmarks.php on line 16
[19-Apr-2010 12:56:58] PHP Warning: mysqli::get_connection_stats():
Couldn't fetch mysqli in D:\Server\Scripts\mysql_benchmarks.php on line 17
--
Edit bug report at http://bugs.php.net/bug.php?id=51605&edit=1
--
Try a snapshot (PHP 5.2):
http://bugs.php.net/fix.php?id=51605&r=trysnapshot52
Try a snapshot (PHP 5.3):
http://bugs.php.net/fix.php?id=51605&r=trysnapshot53
Try a snapshot (PHP 6.0):
http://bugs.php.net/fix.php?id=51605&r=trysnapshot60
Fixed in SVN:
http://bugs.php.net/fix.php?id=51605&r=fixed
Fixed in SVN and need be documented:
http://bugs.php.net/fix.php?id=51605&r=needdocs
Fixed in release:
http://bugs.php.net/fix.php?id=51605&r=alreadyfixed
Need backtrace:
http://bugs.php.net/fix.php?id=51605&r=needtrace
Need Reproduce Script:
http://bugs.php.net/fix.php?id=51605&r=needscript
Try newer version:
http://bugs.php.net/fix.php?id=51605&r=oldversion
Not developer issue:
http://bugs.php.net/fix.php?id=51605&r=support
Expected behavior:
http://bugs.php.net/fix.php?id=51605&r=notwrong
Not enough info:
http://bugs.php.net/fix.php?id=51605&r=notenoughinfo
Submitted twice:
http://bugs.php.net/fix.php?id=51605&r=submittedtwice
register_globals:
http://bugs.php.net/fix.php?id=51605&r=globals
PHP 4 support discontinued: http://bugs.php.net/fix.php?id=51605&r=php4
Daylight Savings: http://bugs.php.net/fix.php?id=51605&r=dst
IIS Stability:
http://bugs.php.net/fix.php?id=51605&r=isapi
Install GNU Sed:
http://bugs.php.net/fix.php?id=51605&r=gnused
Floating point limitations:
http://bugs.php.net/fix.php?id=51605&r=float
No Zend Extensions:
http://bugs.php.net/fix.php?id=51605&r=nozend
MySQL Configuration Error:
http://bugs.php.net/fix.php?id=51605&r=mysqlcfg
