my percona server randomly goes offline please help me to fix this problem.
error log here
Killed
151206 09:54:53 mysqld_safe Number of processes running now: 0
151206 09:54:53 mysqld_safe mysqld restarted
2015-12-06 09:54:54 0 [Warning] Using unique option prefix key_buffer instead of key_buffer_size is deprecated and will be removed in a future release. Please use the full name instead.
2015-12-06 09:54:54 0 [Warning] TIMESTAMP with implicit DEFAULT value is deprecated. Please use --explicit_defaults_for_timestamp server option (see documentation for more details).
2015-12-06 09:54:54 0 [Note] /usr/sbin/mysqld (mysqld 5.6.27-75.0) starting as process 22779 …
2015-12-06 09:54:54 22779 [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.
2015-12-06 09:54:54 22779 [Note] Plugin ‘FEDERATED’ is disabled.
2015-12-06 09:54:54 22779 [Note] InnoDB: Using atomics to ref count buffer pool pages
2015-12-06 09:54:54 22779 [Note] InnoDB: The InnoDB memory heap is disabled
2015-12-06 09:54:54 22779 [Note] InnoDB: Mutexes and rw_locks use GCC atomic builtins
2015-12-06 09:54:54 22779 [Note] InnoDB: Memory barrier is not used
2015-12-06 09:54:54 22779 [Note] InnoDB: Compressed tables use zlib 1.2.8
2015-12-06 09:54:54 22779 [Note] InnoDB: Using Linux native AIO
2015-12-06 09:54:54 22779 [Note] InnoDB: Using CPU crc32 instructions
2015-12-06 09:54:54 22779 [Note] InnoDB: Initializing buffer pool, size = 128.0M
2015-12-06 09:54:54 22779 [Note] InnoDB: Completed initialization of buffer pool
2015-12-06 09:54:54 22779 [Note] InnoDB: Highest supported file format is Barracuda.
2015-12-06 09:54:54 22779 [Note] InnoDB: Log scan progressed past the checkpoint lsn 12993240227
2015-12-06 09:54:54 22779 [Note] InnoDB: Database was not shutdown normally!
2015-12-06 09:54:54 22779 [Note] InnoDB: Starting crash recovery.
2015-12-06 09:54:54 22779 [Note] InnoDB: Reading tablespace information from the .ibd files…
2015-12-06 09:54:54 22779 [Note] InnoDB: Restoring possible half-written data pages
2015-12-06 09:54:54 22779 [Note] InnoDB: from the doublewrite buffer…
InnoDB: Doing recovery: scanned up to log sequence number 12993240326
2015-12-06 09:54:55 22779 [Note] InnoDB: 128 rollback segment(s) are active.
2015-12-06 09:54:55 22779 [Note] InnoDB: Waiting for purge to start
2015-12-06 09:54:55 22779 [Note] InnoDB: Percona XtraDB (http://www.percona.com) 5.6.27-75.0 started; log sequence number 12993240326
2015-12-06 09:54:55 22779 [Note] RSA private key file not found: /var/lib/mysql//private_key.pem. Some authentication plugins will not work.
2015-12-06 09:54:55 22779 [Note] RSA public key file not found: /var/lib/mysql//public_key.pem. Some authentication plugins will not work.
2015-12-06 09:54:55 22779 [Note] Server hostname (bind-address): ‘127.0.0.1’; port: 3306
2015-12-06 09:54:55 22779 [Note] - ‘127.0.0.1’ resolves to ‘127.0.0.1’;
2015-12-06 09:54:55 22779 [Note] Server socket created on IP: ‘127.0.0.1’.
2015-12-06 09:54:55 22779 [Note] Event Scheduler: Loaded 0 events
2015-12-06 09:54:55 22779 [Note] /usr/sbin/mysqld: ready for connections.
Version: ‘5.6.27-75.0’ socket: ‘/var/run/mysqld/mysqld.sock’ port: 3306 Percona Server (GPL), Release 75.0, Revision 8bb53b6
2015-12-06 09:54:57 22779 [ERROR] Can’t create thread to handle request (errno= 11)
Killed
151206 09:54:59 mysqld_safe Number of processes running now: 0
151206 09:54:59 mysqld_safe mysqld restarted
2015-12-06 09:55:00 0 [Warning] Using unique option prefix key_buffer instead of key_buffer_size is deprecated and will be removed in a future release. Please use the full name instead.
2015-12-06 09:55:00 0 [Warning] TIMESTAMP with implicit DEFAULT value is deprecated. Please use --explicit_defaults_for_timestamp server option (see documentation for more details).
2015-12-06 09:55:00 0 [Note] /usr/sbin/mysqld (mysqld 5.6.27-75.0) starting as process 22856 …
2015-12-06 09:55:00 22856 [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.
2015-12-06 09:55:00 22856 [Note] Plugin ‘FEDERATED’ is disabled.
2015-12-06 09:55:00 22856 [Note] InnoDB: Using atomics to ref count buffer pool pages
2015-12-06 09:55:00 22856 [Note] InnoDB: The InnoDB memory heap is disabled
2015-12-06 09:55:00 22856 [Note] InnoDB: Mutexes and rw_locks use GCC atomic builtins
2015-12-06 09:55:00 22856 [Note] InnoDB: Memory barrier is not used
2015-12-06 09:55:00 22856 [Note] InnoDB: Compressed tables use zlib 1.2.8
2015-12-06 09:55:00 22856 [Note] InnoDB: Using Linux native AIO
2015-12-06 09:55:00 22856 [Note] InnoDB: Using CPU crc32 instructions
2015-12-06 09:55:00 22856 [Note] InnoDB: Initializing buffer pool, size = 128.0M
InnoDB: mmap(137363456 bytes) failed; errno 12
2015-12-06 09:55:00 22856 [ERROR] InnoDB: Cannot allocate memory for the buffer pool
2015-12-06 09:55:00 22856 [ERROR] Plugin ‘InnoDB’ init function returned error.
2015-12-06 09:55:00 22856 [ERROR] Plugin ‘InnoDB’ registration as a STORAGE ENGINE failed.
2015-12-06 09:55:00 22856 [ERROR] Unknown/unsupported storage engine: InnoDB
2015-12-06 09:55:00 22856 [ERROR] Aborting
2015-12-06 09:55:00 22856 [Note] Binlog end
2015-12-06 09:55:00 22856 [Note] Shutting down plugin ‘partition’
2015-12-06 09:55:00 22856 [Note] Shutting down plugin ‘PERFORMANCE_SCHEMA’
2015-12-06 09:55:00 22856 [Note] Shutting down plugin ‘ARCHIVE’
2015-12-06 09:55:00 22856 [Note] Shutting down plugin ‘BLACKHOLE’
2015-12-06 09:55:00 22856 [Note] Shutting down plugin ‘INNODB_CHANGED_PAGES’
2015-12-06 09:55:00 22856 [Note] Shutting down plugin ‘INNODB_SYS_DATAFILES’
2015-12-06 09:55:00 22856 [Note] Shutting down plugin ‘INNODB_SYS_TABLESPACES’
2015-12-06 09:55:00 22856 [Note] Shutting down plugin ‘INNODB_SYS_FOREIGN_COLS’
2015-12-06 09:55:00 22856 [Note] Shutting down plugin ‘INNODB_SYS_FOREIGN’
2015-12-06 09:55:00 22856 [Note] Shutting down plugin ‘INNODB_SYS_FIELDS’
2015-12-06 09:55:00 22856 [Note] Shutting down plugin ‘INNODB_SYS_COLUMNS’
2015-12-06 09:55:00 22856 [Note] Shutting down plugin ‘INNODB_SYS_INDEXES’
2015-12-06 09:55:00 22856 [Note] Shutting down plugin ‘INNODB_SYS_TABLESTATS’
2015-12-06 09:55:00 22856 [Note] Shutting down plugin ‘INNODB_SYS_TABLES’
2015-12-06 09:55:00 22856 [Note] Shutting down plugin ‘INNODB_FT_INDEX_TABLE’
2015-12-06 09:55:00 22856 [Note] Shutting down plugin ‘INNODB_FT_INDEX_CACHE’
2015-12-06 09:55:00 22856 [Note] Shutting down plugin ‘INNODB_FT_CONFIG’
2015-12-06 09:55:00 22856 [Note] Shutting down plugin ‘INNODB_FT_BEING_DELETED’
2015-12-06 09:55:00 22856 [Note] Shutting down plugin ‘INNODB_FT_DELETED’
2015-12-06 09:55:00 22856 [Note] Shutting down plugin ‘INNODB_FT_DEFAULT_STOPWORD’
2015-12-06 09:55:00 22856 [Note] Shutting down plugin ‘INNODB_METRICS’
2015-12-06 09:55:00 22856 [Note] Shutting down plugin ‘INNODB_BUFFER_POOL_STATS’
2015-12-06 09:55:00 22856 [Note] Shutting down plugin ‘INNODB_BUFFER_PAGE_LRU’
2015-12-06 09:55:00 22856 [Note] Shutting down plugin ‘INNODB_BUFFER_PAGE’
2015-12-06 09:55:00 22856 [Note] Shutting down plugin ‘INNODB_CMP_PER_INDEX_RESET’
2015-12-06 09:55:00 22856 [Note] Shutting down plugin ‘INNODB_CMP_PER_INDEX’
2015-12-06 09:55:00 22856 [Note] Shutting down plugin ‘INNODB_CMPMEM_RESET’
2015-12-06 09:55:00 22856 [Note] Shutting down plugin ‘INNODB_CMPMEM’
2015-12-06 09:55:00 22856 [Note] Shutting down plugin ‘INNODB_CMP_RESET’
2015-12-06 09:55:00 22856 [Note] Shutting down plugin ‘INNODB_CMP’
2015-12-06 09:55:00 22856 [Note] Shutting down plugin ‘INNODB_LOCK_WAITS’
2015-12-06 09:55:00 22856 [Note] Shutting down plugin ‘INNODB_LOCKS’
2015-12-06 09:55:00 22856 [Note] Shutting down plugin ‘INNODB_TRX’
2015-12-06 09:55:00 22856 [Note] Shutting down plugin ‘XTRADB_RSEG’
2015-12-06 09:55:00 22856 [Note] Shutting down plugin ‘XTRADB_INTERNAL_HASH_TABLES’
2015-12-06 09:55:00 22856 [Note] Shutting down plugin ‘XTRADB_READ_VIEW’
2015-12-06 09:55:00 22856 [Note] Shutting down plugin ‘MyISAM’
2015-12-06 09:55:00 22856 [Note] Shutting down plugin ‘MRG_MYISAM’
2015-12-06 09:55:00 22856 [Note] Shutting down plugin ‘CSV’
2015-12-06 09:55:00 22856 [Note] Shutting down plugin ‘MEMORY’
2015-12-06 09:55:00 22856 [Note] Shutting down plugin ‘sha256_password’
2015-12-06 09:55:00 22856 [Note] Shutting down plugin ‘mysql_old_password’
2015-12-06 09:55:00 22856 [Note] Shutting down plugin ‘mysql_native_password’
2015-12-06 09:55:00 22856 [Note] Shutting down plugin ‘binlog’
2015-12-06 09:55:00 22856 [Note] /usr/sbin/mysqld: Shutdown complete
151206 09:55:00 mysqld_safe mysqld from pid file /var/run/mysqld/mysqld.pid ended