Debian does not use the default garbage collector for sessions. Instead, it sets session.gc_probability to zero and it runs a cron job to clean up old session data in the default directory.
As a result, if your site sets a custom location with session_save_path() you also need to set a value for session.gc_probability, e.g.:
Otherwise, old files in '/home/example.com/sessions' will never get removed!
(PHP 4, PHP 5)
session_save_path — Obtém e/ou define o save path da sessão atual
session_save_path() retorna o path do diretório atual
usado para salvar os dados de sessão. Se
está especificado, o path para aqueles dados que estão salvo será mudado.
session_save_path() precisa ser usada antes de
session_start() para este uso.
Em alguns sistemas operacionais, você pode querer especificar um path em um arquivo de sistema que cuida de muitos arquivos pequenos com eficiência. Por exemplo, em Linux, reiserfs pode oferecer uma performance melhor do que ext2fs.
Veja também a diretiva de configuração session.save_path.
Under PHP for Windows, you can improve the speed, when you store all session-files on ramdisk. A freeware-ramdisk you can download by http://www.techsnack.net/gavotte-ramdisk-free-virtual-hardisk .
A other alternativ is store you session-datas to apc-user-cache (see php-apc-extension).
After a lot of searches, tests and pain, the only one that worked for me was this:
session_save_path(realpath(dirname($_SERVER['DOCUMENT_ROOT']) . '/../session'));
After a search for the cause of a issue causing users to have to login twice, I've found a call to session_save_path() was the culprit.
What was happening was: the session save path was set, a session was opened, some variables were set and the session was closed. This was resulting in an empty file in the specified session save path and of course no session data on the next page load. Oddly, on the second attempt the data was saved as expected.
I found that removing the call to session_save_path() resolved the issue. My final solution was to replace the call to session_save_path($path) with an equivalent call to ini_set('session.save_path', $path).
Session on clustered web servers !
We had problem in PHP session handling with 2 web server cluster. Problem was one servers session data was not available in other server.
So I made a simple configuration in both server php.ini file. Changed session.save_path default value to shared folder on both servers (/mnt/session/).
It works for me. :)
Note that you shouldn't use session_save_path() directly for performing file operations.
It returns the configuration option, not the directory.
As stated in /manual/en/ref.session.php#ini.session.save-path there can be a numeric argument separated with a semicolon in front of the "real" path.
I used the following code to get rid of it:
$sessionpath = session_save_path();
if (strpos ($sessionpath, ";") !== FALSE)
$sessionpath = substr ($sessionpath, strpos ($sessionpath, ";")+1);
Doesn't allow ; to appear in the directory names, but hey.
This is an absolute must if you have an important login on a shared server. Without it, other users of the server can do the following to bypass login:
* Visit login page, browse through cookies and grab the session id.
* Create a PHP script on their account that grabs and sets session variables for a given session id.
* Read and change any values for that session id (for example passwords or session keys), and therefore gain access to the protected area.
All users on web hosting should choose an dir below the HTTP directory struct, but within their user area to store the session files.
dont forget: if you use session_save_path on the page, that registers a variable, you have also to use session_save_path on all the pages, where you access the session-variable. under win32 you can use the double \\ to specify eg "c:\\temp\\"
sometime you need to change session.save_path because server system distributed more then one machine and you can not reach php.ini file example sourceforge.net. Then you can do that with .htaccess file which is kind of configuration file for Apache under one directory. anyway I added
php_value session.save_path /home/groups/f/f4/f4l/tmp/
now my sessions work very well I hope :)