mysql 服务突然中断

故障：mysql服务突然中断，下面是相关日志。请高手帮着给看看，感谢。
Version: '5.1.73'  socket: '/tmp/mysql.sock'  port: 3306  MySQL Community Server (GPL)
150827 13:33:49 mysqld_safe Number of processes running now: 0
150827 13:33:49 mysqld_safe mysqld restarted
150827 13:33:49 [Note] Plugin 'FEDERATED' is disabled.
150827 13:33:49  InnoDB: Initializing buffer pool, size = 16.0M
150827 13:33:49  InnoDB: Completed initialization of buffer pool
InnoDB: Error: pthread_create returned 11
150827 13:33:52 mysqld_safe mysqld from pid file /usr/local/mysql/data/sam.pid ended
150827 23:03:42 [Note] Plugin 'FEDERATED' is disabled.
150827 23:03:42  InnoDB: Initializing buffer pool, size = 16.0M
150827 23:03:42  InnoDB: Completed initialization of buffer pool
150827 23:03:42  InnoDB: Started; log sequence number 0 85355
150827 23:03:43 [Note] Event Scheduler: Loaded 0 events
150827 23:03:43 [Note] /usr/local/mysql/bin/mysqld: ready for connections.