mariadb突然无法启动！显示的pid文件不存在。

新建了pid文件。但是mariadb还是无法启动。一重启pid文件就会消失？怎么办

下面是日志：
170629 17:21:07 mysqld_safe Starting mysqld daemon with databases from /usr/local/mariadb/var
170629 17:21:07 [Note] /usr/local/mariadb/bin/mysqld (mysqld 10.0.23-MariaDB-log) starting as process 4061 ...
170629 17:21:07 [Note] InnoDB: Using mutexes to ref count buffer pool pages
170629 17:21:07 [Note] InnoDB: The InnoDB memory heap is disabled
170629 17:21:07 [Note] InnoDB: Mutexes and rw_locks use GCC atomic builtins
170629 17:21:07 [Note] InnoDB: Memory barrier is not used
170629 17:21:07 [Note] InnoDB: Compressed tables use zlib 1.2.8
170629 17:21:07 [Note] InnoDB: Using CPU crc32 instructions
170629 17:21:07 [Note] InnoDB: Initializing buffer pool, size = 512.0M
170629 17:21:07 [Note] InnoDB: Completed initialization of buffer pool
170629 17:21:07 [Note] InnoDB: Highest supported file format is Barracuda.
170629 17:21:07 [Note] InnoDB: 128 rollback segment(s) are active.
170629 17:21:07 [Note] InnoDB: Waiting for purge to start
170629 17:21:07 [Note] InnoDB: Percona XtraDB (http://www.percona.com) 5.6.26-76.0 started; log sequence number 1921558
170629 17:21:07 [ERROR] mysqld: File './mysql-bin.000160' not found (Errcode: 2 "No such file or directory")
170629 17:21:07 [ERROR] Failed to open log (file './mysql-bin.000160', errno 2)
170629 17:21:07 [ERROR] Could not open log file
170629 17:21:07 [ERROR] Can't init tc log
170629 17:21:07 [ERROR] Aborting

170629 17:21:07 [Note] InnoDB: FTS optimize thread exiting.
170629 17:21:07 [Note] InnoDB: Starting shutdown...
170629 17:21:10 [Note] InnoDB: Shutdown completed; log sequence number 1921568
170629 17:21:10 [Note] /usr/local/mariadb/bin/mysqld: Shutdown complete

170629 17:21:10 mysqld_safe mysqld from pid file /usr/local/mariadb/var/mariadb.pid ended