MariaDB error failed to start, errno 12
This server host about 4 blogs that all run with MariaDB 10. After a few days running, MariaDB service keep failing on this micro EC2 AWS with error like this.
120423 09:13:38 mysqld_safe mysqld from pid file /var/run/mysqld/mysqld.pid ended 120423 09:14:27 mysqld_safe Starting mysqld daemon with databases from /var/lib/mysql 120423 9:14:27 [Note] Plugin 'FEDERATED' is disabled. 120423 9:14:27 InnoDB: The InnoDB memory heap is disabled 120423 9:14:27 InnoDB: Mutexes and rw_locks use GCC atomic builtins 120423 9:14:27 InnoDB: Compressed tables use zlib 1.2.3 120423 9:14:27 InnoDB: Using Linux native AIO 120423 9:14:27 InnoDB: Initializing buffer pool, size = 512.0M InnoDB: mmap(549453824 bytes) failed; errno 12 120423 9:14:27 InnoDB: Completed initialization of buffer pool 120423 9:14:27 InnoDB: Fatal error: cannot allocate memory for the buffer pool 120423 9:14:27 [ERROR] Plugin 'InnoDB' init function returned error. 120423 9:14:27 [ERROR] Plugin 'InnoDB' registration as a STORAGE ENGINE failed. 120423 9:14:27 [ERROR] Unknown/unsupported storage engine: InnoDB 120423 9:14:27 [ERROR] Aborting
Error 12 is
OS error code:(ENOMEM) Out of memory, so of course you could just throw more memory to it. Or you could just enable swap to make MariaDB didn’t crash anymore. By default micro EC2 didn’t have a swap, so we should run a few linux command to make one.
sudo dd if=/dev/zero of=/swaps bs=1M count=1024 sudo mkswap /swaps sudo swapon /swaps
Taadaa!! Your MariaDB instance should run flawlessly now. To make your change run for every reboot, Add this line
/swaps swap swap defaults 0 0 to