ubuntu系统，启动mysql的时候，出现start: Job failed to start，日志如下，这是什么问题？日志看不太明白

Specia_Lee 2015-01-09 02:57:05

150109 10:22:38 [Warning] Using unique option prefix myisam-recover instead of myisam-recover-options is deprecated and will be removed in a future release. Please use the full name instead.
150109 10:22:38 [Note] Plugin 'FEDERATED' is disabled.
150109 10:22:38 InnoDB: The InnoDB memory heap is disabled
150109 10:22:38 InnoDB: Mutexes and rw_locks use GCC atomic builtins
150109 10:22:38 InnoDB: Compressed tables use zlib 1.2.8
150109 10:22:38 InnoDB: Using Linux native AIO
150109 10:22:38 InnoDB: Initializing buffer pool, size = 128.0M
150109 10:22:38 InnoDB: Completed initialization of buffer pool
150109 10:22:38 InnoDB: highest supported file format is Barracuda.
150109 10:22:38 InnoDB: Waiting for the background threads to start
150109 10:22:39 InnoDB: 5.5.40 started; log sequence number 1649678
150109 10:22:39 [Note] Server hostname (bind-address): '127.0.0.1'; port: 3306
150109 10:22:39 [Note] - '127.0.0.1' resolves to '127.0.0.1';
150109 10:22:39 [Note] Server socket created on IP: '127.0.0.1'.
150109 10:22:39 [Note] Event Scheduler: Loaded 0 events
150109 10:22:39 [Note] /usr/sbin/mysqld: ready for connections.
Version: '5.5.40-0ubuntu1' socket: '/var/run/mysqld/mysqld.sock' port: 3306 (Ubuntu)
150109 11:39:43 [Note] /usr/sbin/mysqld: Normal shutdown

150109 11:39:43 [Note] Event Scheduler: Purging the queue. 0 events
150109 11:39:45 [Warning] /usr/sbin/mysqld: Forcing close of thread 44 user: 'root'

150109 11:39:45 [Warning] /usr/sbin/mysqld: Forcing close of thread 43 user: 'root'

150109 11:39:45 [Warning] /usr/sbin/mysqld: Forcing close of thread 38 user: 'root'

150109 11:39:45 InnoDB: Starting shutdown...
150109 11:39:47 InnoDB: Shutdown completed; log sequence number 1656559
150109 11:39:47 [Note] /usr/sbin/mysqld: Shutdown complete

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