innodb_space.txt

参考 https://blog.jcole.us/2013/01/03/a-quick-introduction-to-innodb-ruby/
     https://github.com/jeremycole/innodb_diagrams
	 
	 
innodb_ruby脚本是用来学习INNODB内部结构的，不要用于生产环境
环境Ubuntu 16.04.1 LTS
apt-get install rubygems 安装ruby包管理
gem install innodb_ruby

root@ubuntu:~# innodb_space  测试是否安装成功，如果出现表示成功
Error: System space file (-s) or space file (-f) must be specified; see --help for usage information


采用如下脚本插入测试数据
#!/usr/bin/env ruby

require "mysql"

m = Mysql.new("127.0.0.1", "root", "", "test")

m.query("DROP TABLE IF EXISTS t")

m.query("CREATE TABLE t (i INT UNSIGNED NOT NULL, PRIMARY KEY(i)) ENGINE=InnoDB")

(1..1000000).to_a.shuffle.each_with_index do |i, index|
  m.query("INSERT INTO t (i) VALUES (#{i})")
  puts "Inserted #{index} rows..." if index % 10000 == 0
end


查看整个表空间文件展示表空间由哪些页组成，采用独立表空间
innodb_space -f test/t.ibd space-page-type-regions

root@ubuntu:/var/lib/mysql/test# ls
db.opt  t.frm  t.ibd
root@ubuntu:/var/lib/mysql/test# innodb_space -f t.ibd space-page-type-regions
start       end         count       type                
0           0           1           FSP_HDR            FSP_HDR: Filespace Header / Extent Descriptor 
1           1           1           IBUF_BITMAP        IBUF_BITMAP: Insert Buffer Bookkeeping
2           2           1           INODE              INODE: Index Node Information
3           37          35          INDEX              INDEX: Root page of first index
38          63          26          FREE (ALLOCATED)   ALLOCATED: Reserved but unused page
64          2155        2092        INDEX              
2156        2175        20          FREE (ALLOCATED)    
2176        2176        1           INDEX               
2177        2239        63          FREE (ALLOCATED)    
2240        2240        1           INDEX               
2241        2303        63          FREE (ALLOCATED)    
2304        2304        1           INDEX               
2305        2367        63          FREE (ALLOCATED)    
2368        2368        1           INDEX               
2369        2431        63          FREE (ALLOCATED)    
2432        2432        1           INDEX               
2433        2687        255         FREE (ALLOCATED)

Every index has an "internal" file segment, used for non-leaf pages, and a "leaf" file segment, used for leaf pages
root@ubuntu:/var/lib/mysql/test# innodb_space -f t.ibd space-indexes
id          name                            root        fseg        used        allocated   fill_factor 
41                                          3           internal    3           3           100.00%      
41                                          3           leaf        2129        2464        86.40%

查看单个页的数据，由上面得知2号页为INODE页
root@ubuntu:/var/lib/mysql/test# innodb_space -f t.ibd -p 2 page-dump
我取了部分数据查看，真是看到不少东西，大家可以去尝试下