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.
* Ubuntu or Debian: apt-get install libglib2.0-dev libmysqlclient15-dev zlib1g-dev libpcre3-dev libssl-dev * Fedora, RedHat and CentOS: yum install glib2-devel mysql-devel zlib-devel pcre-devel openssl-devel * openSUSE: zypper install glib2-devel libmysqlclient-devel pcre-devel zlib-devel * MacOSX: port install glib2 mysql5 pcre pkgconfig cmake (You may want to run 'port select mysql mysql5' afterwards)
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_profile后source生效
错误3: [root@GZ-APP-BAK01 ~]# mydumper --help|more mydumper: error while loading shared libraries: libmysqlclient.so.18: cannot open shared object file: No such file or directory [root@GZ-APP-BAK01 ~]# mydumper mydumper: error while loading shared libraries: libmysqlclient.so.18: cannot open shared object file: No such file or directory ###出现上述错误,应考虑建立软链 # which libmysqlclient.so.18 /app/soft/mysql/lib/libmysqlclient.so.18 # ln -s /app/soft/mysql/lib/libmysqlclient.so.18 /usr/lib/libmysqlclient.so.18
错误4: # mydumper -uusr1 -ppwd -B blos -o /tmp/bak option parsing failed: Error parsing option -r, try --help ###参数和字符串不能连着写,笔者刚开始是也是丈二和尚摸不着头脑。
# mydumper --version mydumper 0.6.2, built against MySQL 5.6.22
7、获取帮助 # mydumper --help|more Usage: mydumper [OPTION...] multi-threaded MySQL dumping
Help Options: -?, --help Show help options
Application Options: -B, --database Database to dump -T, --tables-list Comma delimited table list to dump (does not exclude regex option) -o, --outputdir Directory to output files to -s, --statement-size Attempted size of INSERT statement in bytes, default 1000000 -r, --rows Try to split tables into chunks of this many rows. This option turns off --chunk-filesize -F, --chunk-filesize Split tables into chunks of this output file size. This value is in MB -c, --compress Compress output files -e, --build-empty-files Build dump files even if no data available from table -x, --regex Regular expression for 'db.table' matching -i, --ignore-engines Comma delimited list of storage engines to ignore -m, --no-schemas Do not dump table schemas with the data -k, --no-locks Do not execute the temporary shared read lock. WARNING: This will cause inconsistent backups --less-locking Minimize locking time on InnoDB tables. -l, --long-query-guard Set long query timer in seconds, default 60 -K, --kill-long-queries Kill long running queries (instead of aborting) -D, --daemon Enable daemon mode -I, --snapshot-interval Interval between each dump snapshot (in minutes), requires --daemon, default 60 -L, --logfile Log file name to use, by default stdout is used --tz-utc SET TIME_ZONE='+00:00' at top of dump to allow dumping of TIMESTAMP data when a server has data in different time zones or data is being moved between servers with different time zones, defaults to on use --skip-tz-utc to disable. --skip-tz-utc --use-savepoints Use savepoints to reduce metadata locking issues, needs SUPER privilege --success-on-1146 Not increment error count and Warning instead of Critical in case of table doesn't exist --lock-all-tables Use LOCK TABLE for all, instead of FTWRL -h, --host The host to connect to -u, --user Username with privileges to run the dump -p, --password User password -P, --port TCP/IP port to connect to -S, --socket UNIX domain socket file to use for connection -t, --threads Number of threads to use, default 4 -C, --compress-protocol Use compression on the MySQL connection -V, --version Show the program version and exit -v, --verbose Verbosity of output, 0 = silent, 1 = errors, 2 = warnings, 3 = info, default 2