InnoDB: Error number 24 means ‘Too many open files’.--转载

一.问题的描述

备份程序 执行前滚的时候报错。(-apply-log)

InnoDB: Errornumber 24 means 'Too many open files'.

InnoDB: Some operatingsystem error numbers are described at

InnoDB: http://dev.mysql.com/doc/mysql/en/Operating_System_error_codes.html

InnoDB: File name/home/nice/backup/mysql/var.20121211021656/user_db_20121123/tuser_like_core.ibd

InnoDB: File operationcall: 'open'.

InnoDB: Cannot continueoperation.

innobackup:Error:

二.问题分析

openfiles 开的小了。

mysql的open_file_limit受制于以下几个参数

max_connections、 table_open_cache 、open_files_limit 以及 /etc/security/limits.conf中的配置。

max_connections和 table_open_cache 与open_files_limit 的关系：

max_1 = 10 + max_connections + table_cache * 2;

max_2 = max_connections * 5;

max_3 = max_os_open_files;//操作系统单个进程最大允许打开文件句柄（文件描述符）。

open_files_limit= max( max_1, max_2 ) > max_3 ? max_3 : max ( max_1, max_2);

综合分析发现，open_files_limit  | 10240

而目前ibd表已经10800个了。

三.解决问题

1.my.cnf  配置 open_files_limit         = 20480

重启mysql 发现没有变化,open_files_limit  | 10240。

2.ulimit -a

core file size          (blocks, -c) unlimited
data seg size           (kbytes, -d) unlimited
file size               (blocks, -f) unlimited
pending signals                 (-i) 1024
max locked memory       (kbytes, -l) 32
max memory size         (kbytes, -m) unlimited
open files                      (-n) 1024
pipe size            (512 bytes, -p) 8
POSIX message queues     (bytes, -q) 819200
stack size              (kbytes, -s) 10240
cpu time               (seconds, -t) unlimited
max user processes              (-u) 137216
virtual memory          (kbytes, -v) unlimited
file locks                      (-x) unlimited

3.vi /etc/security/limits.conf,添加

mysql            soft    nofile          8192
mysql            hard    nofile          20480

4.经过前三步，重启mysql。

重启mysql 发现,open_files_limit  | 20480。

5.修改OS用户配置文件

经过前四步，虽然在mysql中 看open_files_limit  | 20480,但ibbackup还是在前滚时报错。报，open_file不够。怀疑 还是没有生效。

ulimit -a

core file size          (blocks, -c) unlimited
data seg size           (kbytes, -d) unlimited
file size               (blocks, -f) unlimited
pending signals                 (-i) 1024
max locked memory       (kbytes, -l) 32
max memory size         (kbytes, -m) unlimited
open files                      (-n) 1024
pipe size            (512 bytes, -p) 8
POSIX message queues     (bytes, -q) 819200
stack size              (kbytes, -s) 10240
cpu time               (seconds, -t) unlimited
max user processes              (-u) 137216
virtual memory          (kbytes, -v) unlimited
file locks                      (-x) unlimited

于是，修改OS用户配置文件

分别查看了.bash_profile 、.bashrc 、/etc/bashrc；

发现，.bash_profile调用 .bashrc ，.bashrc调用 /etc/bashrc

发现，/etc/bashrc 中有

ulimit -S -c unlimited > /dev/null 2>&1
在这一行之后 添加

ulimit -n 20480 >/dev/null 2>&1

6.重启mysql ,执行备份程序，在--apply-log，还是报错，报，open_file不够

InnoDB: Errornumber 24 means 'Too many open files'.

InnoDB: Some operatingsystem error numbers are described at

InnoDB: http://dev.mysql.com/doc/mysql/en/Operating_System_error_codes.html

7.修改innodb_open_files 参数

之前这个参数，设置成500.这次修改到1000.

重启mysql 解决问题

四.关于Operating_System_error_codes.html

Linux System Error Codes

The following tableprovides a list of some common Linux system error codes. For a more completelist, see Linux source code.

Number	Macro	Description
1	EPERM	Operation not permitted
2	ENOENT	No such file or directory
3	ESRCH	No such process
4	EINTR	Interrupted system call
5	EIO	I/O error
6	ENXIO	No such device or address
7	E2BIG	Arg list too long
8	ENOEXEC	Exec format error
9	EBADF	Bad file number
10	ECHILD	No child processes
11	EAGAIN	Try again
12	ENOMEM	Out of memory
13	EACCES	Permission denied
14	EFAULT	Bad address
15	ENOTBLK	Block device required
16	EBUSY	Device or resource busy
17	EEXIST	File exists
18	EXDEV	Cross-device link
19	ENODEV	No such device
20	ENOTDIR	Not a directory
21	EISDIR	Is a directory
22	EINVAL	Invalid argument
23	ENFILE	File table overflow
24	EMFILE	Too many open files
25	ENOTTY	Inappropriate ioctl for device
26	ETXTBSY	Text file busy
27	EFBIG	File too large
28	ENOSPC	No space left on device
29	ESPIPE	Illegal seek
30	EROFS	Read-only file system
31	EMLINK	Too many links

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作者：凤凰舞者 qq:578989855