延迟mysql更新查询Joomla 2.5

I'm getting a delay in session update query when database is selected as session handler in Joomla 2.5, which doesn't let me login. Also it only happens when i enable a module(made by me). So basically what the module does is send an ajax request to a custom component and returns some json data, which is further processed.

As session write callback is called when the php rendering is completed, update query to session table is executed. Only thing which i was able to find:

When page is opened(as guest), following request takes place:

• index.php (session write, #1)
• index.php?option=com_component&task=auth (session write gets delayed here, #2)

On login:

• index.php (for login, which redirects to index.php again, #3)
• index.php (after login, session is populated with user data, #4)

Sometimes #2 request is finished between these requests and session is replaced with guest data, in turn logging out the user.

• index.php?option=com_component&task=auth (ajax call, #5)

I was hoping if there is any workaround. Also this doesn't happen all the time, which is making it more complicated.