[TAJO-1831] Add a shutdown hook manager in order to set priorities

• Type: Improvement
• Status: Resolved
• Priority: Minor
• Resolution: Fixed
• Fix Version/s: 0.11.0, 0.12.0
• Component/s: Java Client, RPC, TajoMaster, Worker
• Assignee: Jinho Kim
• Reporter: Jinho Kim
• Created: 09/Sep/15 07:26
• Updated: 11/Sep/15 06:49
• Resolved: 11/Sep/15 05:48

Description

Sometimes, event-group thread of netty’s is not stopped. because jvm will start a shutdown-hook after all thread is stopped without kill signal. it is dead-lock state.
We should explicitly call to shutdown the event-group thread of netty’s and should set a shutdown-hook order

For example, before you start up TajoMaster, runs tsql, you can find deadlock