instance variable life span in controller

I understand that rails drops all instance variables created in normal
controller action after rendering view templates.

But I have the following problem that a normal controller action has
several before_filter and after_filter, which all using same set of
variables fetching from database.

I do not think I explained my problem clearly.

After you read the above post, you maybe think that I can just create
another before_filter which is at the very beginning of this process,
and just set an instance variable like @app_setting = App.first, and
all the following method can use this variable.

But because all the before_filter and after_filter are wrapped to
almost all actions in my app, so what I really want is that whether
there is something that can persists its value between different

You can do like

def get_title
       @title = @first_setting.title

def get_title
        @title = first_app_setting.title