Open Source Document Management System | OpenKM

i am using mysql with openKM .it is working fine but here the problem is
mysql connection will be closing after 8 hours because of the time between two hits to the server.

i am getting error like SocketException, because of connections were closed ,

for this what do have to do?

for more clearance of the Exception i am getting ,please take look into attached file.
please help me.

you must make some change in openkm-ds.xml file take a look for property idle-timeout-minutes