Mysql unexpected stop

[inori0821]

These days i found the mysql service stopped very frequently. After check the error log, it shows below:

19:43:10 30062 [Note] Plugin 'FEDERATED' is disabled.
2014-10-14 19:43:10 30062 [Note] InnoDB: Using atomics to ref count buffer pool pages
2014-10-14 19:43:10 30062 [Note] InnoDB: The InnoDB memory heap is disabled
2014-10-14 19:43:10 30062 [Note] InnoDB: Mutexes and rw_locks use GCC atomic builtins
2014-10-14 19:43:10 30062 [Note] InnoDB: Compressed tables use zlib 1.2.8
2014-10-14 19:43:10 30062 [Note] InnoDB: Not using CPU crc32 instructions
2014-10-14 19:43:10 30062 [Note] InnoDB: Initializing buffer pool, size = 16.0M
2014-10-14 19:43:10 30062 [Note] InnoDB: Completed initialization of buffer pool
2014-10-14 19:43:10 30062 [Note] InnoDB: Highest supported file format is Barracuda.
2014-10-14 19:43:10 30062 [Note] InnoDB: The log sequence numbers 6796306 and 6796306 in ibdata files do not match the log sequence number 8319397 in the ib_logfiles!
2014-10-14 19:43:10 30062 [Note] InnoDB: Database was not shutdown normally!
2014-10-14 19:43:10 30062 [Note] InnoDB: Starting crash recovery.
2014-10-14 19:43:10 30062 [Note] InnoDB: Reading tablespace information from the .ibd files...
2014-10-14 19:43:10 30062 [Note] InnoDB: Restoring possible half-written data pages
2014-10-14 19:43:10 30062 [Note] InnoDB: from the doublewrite buffer...
2014-10-14 19:43:10 30062 [Note] InnoDB: 128 rollback segment(s) are active.
2014-10-14 19:43:10 30062 [Note] InnoDB: Waiting for purge to start
2014-10-14 19:43:10 30062 [Note] InnoDB: 5.6.16 started; log sequence number 8319397
2014-10-14 19:43:10 30062 [Note] RSA private key file not found: /opt/lampp/var/mysql//private_key.pem. Some authentication plugins will not work.
2014-10-14 19:43:10 30062 [Note] RSA public key file not found: /opt/lampp/var/mysql//public_key.pem. Some authentication plugins will not work.
2014-10-14 19:43:10 30062 [Note] Event Scheduler: Loaded 0 events
2014-10-14 19:43:10 30062 [Note] /opt/lampp/sbin/mysqld: ready for connections.
Version: '5.6.16' socket: '/opt/lampp/var/mysql/mysql.sock' port: 0 Source distribution

Any help please? Now I have to start the service manually again and again.