Unable to create lockmanager

I’m using Openhab 1.7.1 for monitoring my Energmeter.
I use persistance with MySQL on a RPi 2.

Sometimes the system hangs. Then I get:
“Unable to create lockmanager”
But I didn’t change anything!

Any suggestions?

pi@raspberrypi:~ $
pi@raspberrypi:~ $
pi@raspberrypi:~ $ sudo service openhab status
● openhab.service - Starts and stops the openHAB Home Automation Bus
Loaded: loaded (/usr/lib/systemd/system/openhab.service; disabled)
Active: inactive (dead)
Docs: http://www.openhab.org

Dec 17 13:45:57 raspberrypi openhab.sh[640]: at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
Dec 17 13:45:57 raspberrypi openhab.sh[640]: at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
Dec 17 13:45:57 raspberrypi openhab.sh[640]: at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
Dec 17 13:45:57 raspberrypi openhab.sh[640]: at java.lang.reflect.Method.invoke(Method.java:483)
Dec 17 13:45:57 raspberrypi openhab.sh[640]: at org.eclipse.equinox.launcher.Main.invokeFramework(Main.java:629)
Dec 17 13:45:57 raspberrypi openhab.sh[640]: at org.eclipse.equinox.launcher.Main.basicRun(Main.java:584)
Dec 17 13:45:57 raspberrypi openhab.sh[640]: at org.eclipse.equinox.launcher.Main.run(Main.java:1438)
Dec 17 13:45:57 raspberrypi openhab.sh[640]: at org.eclipse.equinox.launcher.Main.main(Main.java:1414)
Dec 17 13:45:57 raspberrypi openhab.sh[640]: Invalid Configuration LocationLocking is not possible in the directory “/var/lib/openhab/workspace/org.eclipse.osgi”. A common reason is that the file system or Runtime Environment does not support file locking for that location. Please choose a different locati…
Dec 17 13:45:57 raspberrypi openhab.sh[640]: Unable to create lock manager.
Hint: Some lines were ellipsized, use -l to show in full.
pi@raspberrypi:~ $
pi@raspberrypi:~ $