Trouble with login admin I'm having trouble in the control panel. I'm get logged out all the time and I can't find the reason. The "Your session has ended" modal window appears all the time, I can just do a refresh and it stays in the control panel (logged in). Sometimes i'm also thrown out completely.

What did i tried to solve it (together)


'overridePhpSessionLocation' => true or false doesn't seem to make a difference
removed my cookies
craft/storage/runtime is on 777
removed database content of craft_sessions
removed craft/storage/runtime multiple times, it's created again. 
craft/storage/runtime/sessions stays empty and is on 777


This is the error in the log files:


  2016/02/09 20:31:12 [warning] [application] Tried to restore session from a cookie, but the given hashed database token value does not appear to belong to the given login name. Hashed db value: cf349cc791478ab96e9229dad6367f1358f1404bczozMjoiMGQ0SUJxelZYYmdNUVh6WDhVdHhBODFUb0lWb2dGT0wiOw== and loginName: REDACTED


(I edited the question to narrow down the problem. it's kinda driving me nuts)
in the end, for me making

/opt/www/dave/web/tmp 


writable for craft was the solution. 
thanks for all the feedback!