py_innodb_page_info工具使用

此工具是《MySQL技术内幕 InnoDB存储引擎》作者姜承尧写的用来分析表空间中的各页得类型和信息，用python编写。此工具由三个文件py_innodb_page_info.py和mylib.py以及include.py组成。需要放在同一个目录下，chmod 755 这三个文件的权限。

#! /usr/bin/env python 
#encoding=utf-8
import mylib
from sys import argv
from mylib import myargv

if __name__ == '__main__':
        myargv = myargv(argv)
        if myargv.parse_cmdline() == 0:
                pass
        else:
                mylib.get_innodb_page_type(myargv)

#encoding=utf-8
import os
import include
from include import *

TABLESPACE_NAME='D:\\mysql_data\\test\\t.ibd'
VARIABLE_FIELD_COUNT = 1
NULL_FIELD_COUNT = 0

class myargv(object):
        def __init__(self, argv):
                self.argv = argv
                self.parms = {}
                self.tablespace = ''

        def parse_cmdline(self):
                argv = self.argv
                if len(argv) == 1:
                        print 'Usage: python py_innodb_page_info.py [OPTIONS] tablespace_file'
                        print 'For more options, use python py_innodb_page_info.py -h'
                        return 0 
                while argv:
                        if argv[0][0] == '-':
                                if argv[0][1] == 'h':
                                        self.parms[argv[0]] = ''
                                        argv = argv[1:]
                                        break
                                if argv[0][1] == 'v':
                                        self.parms[argv[0]] = ''
                                        argv = argv[1:]
                                else:
                                        self.parms[argv[0]] = argv[1]
                                        argv = argv[2:]
                        else:
                                self.tablespace = argv[0]
                                argv = argv[1:]
                if self.parms.has_key('-h'):
                        print 'Get InnoDB Page Info'
                        print 'Usage: python py_innodb_page_info.py [OPTIONS] tablespace_file\n'
                        print 'The following options may be given as the first argument:'
                        print '-h        help '
                        print '-o output put the result to file'
                        print '-t number thread to anayle the tablespace file'
                        print '-v        verbose mode'
                        return 0
                return 1

def mach_read_from_n(page,start_offset,length):
        ret = page[start_offset:start_offset+length]
        return ret.encode('hex')

def get_innodb_page_type(myargv):
        f=file(myargv.tablespace,'rb')
        fsize = os.path.getsize(f.name)/INNODB_PAGE_SIZE
        ret = {}
        for i in range(fsize):
                page = f.read(INNODB_PAGE_SIZE)
                page_offset = mach_read_from_n(page,FIL_PAGE_OFFSET,4)
                page_type = mach_read_from_n(page,FIL_PAGE_TYPE,2)
                if myargv.parms.has_key('-v'):
                        if page_type == '45bf':
                                page_level = mach_read_from_n(page,FIL_PAGE_DATA+PAGE_LEVEL,2)
                                print "page offset %s, page type <%s>, page level <%s>"%(page_offset,innodb_page_type[page_type],page_level)
                        else:
                                print "page offset %s, page type <%s>"%(page_offset,innodb_page_type[page_type])
                if not ret.has_key(page_type):
                        ret[page_type] = 1
                else:
                        ret[page_type] = ret[page_type] + 1
        print "Total number of page: %d:"%fsize
        for type in ret:
                print "%s: %s"%(innodb_page_type[type],ret[type])

#include.py
#encoding=utf-8
INNODB_PAGE_SIZE = 16*1024*1024

# Start of the data on the page
FIL_PAGE_DATA = 38


FIL_PAGE_OFFSET = 4 # page offset inside space
FIL_PAGE_TYPE = 24 # File page type

# Types of an undo log segment */
TRX_UNDO_INSERT = 1
TRX_UNDO_UPDATE = 2

# On a page of any file segment, data may be put starting from this offset
FSEG_PAGE_DATA = FIL_PAGE_DATA

# The offset of the undo log page header on pages of the undo log
TRX_UNDO_PAGE_HDR = FSEG_PAGE_DATA

PAGE_LEVEL = 26 #level of the node in an index tree; the leaf level is the level 0 */

innodb_page_type={
        '0000':u'Freshly Allocated Page',
        '0002':u'Undo Log Page',
        '0003':u'File Segment inode',
        '0004':u'Insert Buffer Free List',
        '0005':u'Insert Buffer Bitmap',
        '0006':u'System Page',
        '0007':u'Transaction system Page',
        '0008':u'File Space Header',
        '0009':u')'扩展描述页',
        '000a':u'Uncompressed BLOB Page',
        '000b':u'1st compressed BLOB Page',
        '000c':u'Subsequent compressed BLOB Page',
        '45bf':u'B-tree Node'
        }

innodb_page_direction={
        '0000': 'Unknown(0x0000)',
        '0001': 'Page Left',
        '0002': 'Page Right',
        '0003': 'Page Same Rec',
        '0004': 'Page Same Page',
        '0005': 'Page No Direction',
        'ffff': 'Unkown2(0xffff)'
}


INNODB_PAGE_SIZE=1024*16 # InnoDB Page 16K

使用方式

将这三个文件放在同一个路径下

[root@vast python]# pwd
/data/python
[root@vast python]# ll
total 12
-rwxr-xr-x 1 root root 1263 Oct 16 11:24 include.py
-rwxr-xr-x 1 root root 2179 Oct 16 11:24 mylib.py
-rwxr-xr-x 1 root root  234 Oct 16 11:23 py_innodb_page_info.py

[root@vast python]# python py_innodb_page_info.py  /data/mydb/vastdata/t1.ibd 
Total number of page: 576: #分配的页数目
Freshly Allocated Page: 489 #空闲页数目
Insert Buffer Bitmap: 1 #系统Insert Buffer Bitmap拥有的页数目
File Space Header: 1 #系统File Space Header拥有的页数目
B-tree Node: 84 #存放数据的数据页数目
File Segment inode: 1 #系统File Segment inode拥有的页数目

加 -v 会显示出t2.ibd这个数据文件中的页的分布

[root@vast python]# python py_innodb_page_info.py -v /data/mydb/vastdata/t2.ibd 
page offset 00000000, page type
page offset 00000001, page type
page offset 00000002, page type
page offset 00000003, page type , page level <0000>
page offset 00000000, page type
page offset 00000000, page type
Total number of page: 6:
Freshly Allocated Page: 2
Insert Buffer Bitmap: 1
File Space Header: 1
B-tree Node: 1
File Segment inode: 1