yes, i know, a file handler don't need to update mtime, they have "atime", but for a drive which not local, or sql_session_handler, a remote sql server, it's nightmare to send session data every page load

we need to detect whether "it's REALLY need to update session data"

I'll implement by checking hash of serialized session data.
Saving unneeded session writes is good for many apps.

Will be available 5.6 or later.

Is there any configuration so avoid this new behavior? I myself manage the session expiration in the DB and need that every page load force a write even if nothing has changed.

I checked here and couldn't find anything about this new feature:

http://php.net/manual/en/session.configuration.php

This is breaking my code right now... could we implement a way to configure this?

Actually I found a work around adding this in my session close method :

    public function close() {
        $this->write($this->id, serialize($_SESSION));
        return true;
    }

It's fine but if you please let me know if you are planning to have a way to configure this so I will remove my code.