MySQL Daemon failed to start

[root@server /]# tail -f /var/log/mysqld.log

121126 22:43:33 mysqld_safe Starting mysqld daemon with databases from /var/lib/mysql
121126 22:43:33 [Note] Plugin 'FEDERATED' is disabled.
121126 22:43:33 InnoDB: The InnoDB memory heap is disabled
121126 22:43:33 InnoDB: Mutexes and rw_locks use GCC atomic builtins
121126 22:43:33 InnoDB: Compressed tables use zlib 1.2.3
121126 22:43:33 InnoDB: Using Linux native AIO
121126 22:43:33 InnoDB: Initializing buffer pool, size = 128.0M
121126 22:43:33 InnoDB: Completed initialization of buffer pool

InnoDB: Error: pthread_create returned 11

121126 22:43:33 mysqld_safe mysqld from pid file /var/run/mysqld/mysqld.pid ended

I have fixed this by using the following way.

1. Increased my vps RAM from 512 to 1024MB
2. [root@server /]# ulimit -s unlimited
3. [root@server /]# service mysqld start