mydumper是针对mysql数据库备份的一个轻量级第三方的开源工具，备份方式术语逻辑备份。它支持多线程，备份速度远高于原生态的mysqldump以及众多优异特性。因此该工具是DBA们的不二选择。本文主要描述该工具的安装及其出现异常的解决方法。
1、mydumper特性(直接参考readme)
? * Parallelism (hence, speed) and performance (avoids expensive character set conversion routines, efficient code overall)
? * Easier to manage output (separate files for tables, dump metadata, etc, easy to view/parse data)
? * Consistency - maintains snapshot across all threads, provides accurate master and slave log positions, etc
? * Manageability - supports PCRE for specifying database and tables inclusions and exclusions
? It does not support schema dumping and leaves that to 'mysqldump --no-data'
2、获取mydumper及安装方法
下载地址：https://launchpad.net/mydumper
== How to build it? ==
Run:
?cmake .
?make
One needs to install development versions of required libaries (MySQL, GLib, ZLib, PCRE):
NOTE: you must use the correspondent mysql devel package.
One has to make sure, that pkg-config, mysql_config, pcre-config are all in $PATH
Binlog dump is disabled by default to compile with it you need to add -DWITH_BINLOG=ON to cmake options
###如果要使用binlog dump在编译的时候需要使用-DWITH_BINLOG=ON
3、快照工作原理
== How does consistent snapshot work? ==
This is all done following best MySQL practices and traditions:
* As a precaution, slow running queries on the server either abort the dump, or get killed
* Global write lock is acquired ("FLUSH TABLES WITH READ LOCK")
* Various metadata is read ("SHOW SLAVE STATUS","SHOW MASTER STATUS")
* Other threads connect and establish snapshots ("START TRANSACTION WITH CONSISTENT SNAPSHOT")
** On pre-4.1.8 it creates dummy InnoDB table, and reads from it.
* Once all worker threads announce the snapshot establishment, master executes "UNLOCK TABLES" and starts queueing jobs.
This for now does not provide consistent snapshots for non-transactional engines - support for that is expected in 0.2 :)
4、如何过滤数据库
== How to exclude (or include) databases? ==
Once can use --regex functionality, for example not to dump mysql and test databases:
?mydumper --regex '^(?!(mysql|test))'
Of course, regex functionality can be used to describe pretty much any list of tables.
== How to exclude MERGE or Federated tables ==
Use same --regex exclusion syntax. Again, engine-specific behaviors are targetted for 0.2
5、实际安装过程
# ls mydump*
mydumper-0.6.2.tar.gz
# tar -xvf mydumper-0.6.2.tar.gz
# cd mydumper-0.6.2
[root@GZ-APP-BAK01 mydumper-0.6.2]# cmake .
[root@GZ-APP-BAK01 mydumper-0.6.2]# make && make install
6、安装过程中的异常
错误1：
CMake Error: The following variables are used in this project, but they are set to NOTFOUND.
Please set them or make sure they are set and tested correctly in the CMake files:
PCRE_INCLUDE_DIR (ADVANCED)
? used as include directory in directory /root/mydumper-0.6.2
PCRE_PCRE_LIBRARY (ADVANCED)
? ? linked by target "mydumper" in directory /root/mydumper-0.6.2
? ? linked by target "myloader" in directory /root/mydumper-0.6.2
###需要安装pcre-devel包，yum install pcre-devel?
错误2：
CMake Error: The following variables are used in this project, but they are set to NOTFOUND.
Please set them or make sure they are set and tested correctly in the CMake files:
MYSQL_INCLUDE_DIR (ADVANCED)
? used as include directory in directory /home/robin/mydumper-0.6.2
? used as include directory in directory /home/robin/mydumper-0.6.2
? used as include directory in directory /home/robin/mydumper-0.6.2
###出现上述错误，是由于没有配置MYSQL_INCLUDE_DIR目录。
###如果是编译安装到非缺省路径，可以将mysql安装路径添加到/etc/profile或者家目录~/.bash_