PostgreSQL goes down unexpectedly and does not restart using rhc tools on OpenShift Online

Issue

• PostgreSQL goes down and does not restart using rhc tools on OpenShift Online. It throws below error :

"OperationalError: could not connect to server: Connection timed out
Is the server running on host "UUID-application.rhcloud.com" and accepting TCP/IP connections on port 60691?"

at restart attempt below error occurs :

$ rhc cartridge restart postgresql-9.2 --app applicationName
Restarting postgresql-9.2 ...
Unable to complete the requested operation due to: Failed to correctly execute all parallel operations.