mysql_error:Error starting thread: Resource temporarily unavailable

121031 18:53:17  InnoDB: Unable to open the first data file
InnoDB: Error in opening ./ibdata1
121031 18:53:17  InnoDB: Operating system error number 11 in a file operation.
InnoDB: Error number 11 means 'Resource temporarily unavailable'.
InnoDB: Some operating system error numbers are described at
InnoDB: http://dev.mysql.com/doc/refman/5.5/en/operating-system-error-codes.html
121031 18:53:17 InnoDB: Could not open or create data files.
121031 18:53:17 InnoDB: If you tried to add new data files, and it failed here,
121031 18:53:17 InnoDB: you should now edit innodb_data_file_path in my.cnf back
121031 18:53:17 InnoDB: to what it was, and remove the new ibdata files InnoDB created 
121031 18:53:17 InnoDB: in this failed attempt. InnoDB only wrote those files full of 
121031 18:53:17 InnoDB: zeros, but did not yet use them in any way. But be careful: do not
121031 18:53:17 InnoDB: remove old data files which contain your precious data!
121031 18:53:17 [ERROR] Plugin 'InnoDB' init function returned error.
121031 18:53:17 [ERROR] Plugin 'InnoDB' registration as a STORAGE ENGINE failed. 
121031 18:53:17 [ERROR] Unknown/unsupported storage engine: INNODB
121031 18:53:17 [ERROR] Aborting

121031 18:53:17 [Note] /usr/local/mysql/bin/mysqld: Shutdown complete

121031 18:53:17 mysqld_safe mysqld from pid file /data/mysql/mysql_3301/mysql_3301.pid ended
121031 18:54:29 mysqld_safe Starting mysqld daemon with databases from /data/mysql/mysql_3301
121031 18:54:29 [Warning] The syntax '--log-slow-queries' is deprecated and will be removed in a future release. Please use '--slow-
query-log'/'--slow-query-log-file' instead.
121031 18:54:29 InnoDB: The InnoDB memory heap is disabled
121031 18:54:29 InnoDB: Mutexes and rw_locks use GCC atomic builtins
121031 18:54:29 InnoDB: Compressed tables use zlib 1.2.3
121031 18:54:30 InnoDB: Initializing buffer pool, size = 2.9G
121031 18:54:30 InnoDB: Completed initialization of buffer pool
InnoDB: Unable to lock ./ibdata1, error: 11
InnoDB: Check that you do not already have another mysqld process
InnoDB: using the same InnoDB data or log files.
121031 18:54:30  InnoDB: Retrying to lock the first data file
InnoDB: Unable to lock ./ibdata1, error: 11
InnoDB: Check that you do not already have another mysqld process
InnoDB: using the same InnoDB data or log files.
121031 18:54:30  InnoDB: Retrying to lock the first data file
InnoDB: Unable to lock ./ibdata1, error: 11
InnoDB: Check that you do not already have another mysqld process
InnoDB: using the same InnoDB data or log files.
InnoDB: Unable to lock ./ibdata1, error: 11
InnoDB: Check that you do not already have another mysqld process
InnoDB: using the same InnoDB data or log files.
InnoDB: Unable to lock ./ibdata1, error: 11

 

 

 

InnoDB: Error number 11 means 'Resource temporarily unavailable'.

 

 

Error starting thread: Resource temporarily unavailable
 
经过深入查询，排除了内存，句柄数等问题. 并且切换至root用户打开大量线程时没有问题。试着调整ulimit各项参数,最后发现是"max user processes "参数有问题，通过root用户调整大小至 12000,线程数也随着增大.
 
 
Java代码
root@blog:/home/badqiu# ulimit -a
core file size          (blocks, -c) 0
data seg size           (kbytes, -d) unlimited
scheduling priority             (-e) 0
file size               (blocks, -f) unlimited
pending signals                 (-i) 143360
max locked memory       (kbytes, -l) 32
max memory size         (kbytes, -m) unlimited
open files                      (-n) 2048
pipe size            (512 bytes, -p) 8
POSIX message queues     (bytes, -q) 819200
real-time priority              (-r) 0
stack size              (kbytes, -s) 8192
cpu time               (seconds, -t) unlimited
max user processes              (-u) 2046
virtual memory          (kbytes, -v) unlimited
file locks                      (-x) unlimited
 
在linux系统内生效。
vi /etc/security/limits.conf
 
Java代码
* soft nproc 12000
* hard nproc 12000
 nproc就是"max user processes"，完整描述是: nproc - max number of processes
 
参数含义:
 
单个用户可以启动的线程数，因为进程也会启动一个线程，所以也间接对进程数有限制。
 
注意：
 
该参数只对普通用户有用，root用户不在此限制。 所以用root用户可以启动几万个线程，无法重现这个问题.