Dear Sir !
The long sleep time in db occours when you use php application .
This causes PHP to connect to the database, execute queries, remove the authentication for the connection, and then leave the connection open.
Please set the following line to /etc/my.cnf.
wait_timeout = 180
interactive_timeout = 180
thats all.
mysql will drop connection after 3 minutes.
i can set this for you,on teamviewer access.
regards
g