Ecosyste.ms: Awesome

An open API service indexing awesome lists of open source software.

https://github.com/mydumper/mydumper

Official MyDumper Project
https://github.com/mydumper/mydumper

database mariadb multithreading mysql percona replication tidb

Last synced: 3 months ago
JSON representation

Official MyDumper Project

Lists

README 

        
[![CircleCI](https://circleci.com/gh/mydumper/mydumper/tree/master.svg?style=svg)](https://circleci.com/gh/mydumper/mydumper/tree/master)



 # What is MyDumper?

MyDumper is a MySQL Logical Backup Tool. It has 2 tools:

* `mydumper` which is responsible to export a consistent backup of MySQL databases

* `myloader` reads the backup from mydumper, connects to the destination database and imports the backup.



Both tools use multithreading capabilities.


MyDumper is Open Source and maintained by the community, it is not a Percona, MariaDB or MySQL product.



# Why do we need MyDumper?

* 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



## How to install mydumper/myloader?



First get the correct url from the [releases section](https://github.com/maxbube/mydumper/releases) then:



### RedHat / Centos



```bash

release=$(curl -Ls -o /dev/null -w %{url_effective} https://github.com/mydumper/mydumper/releases/latest | cut -d'/' -f8)

yum install https://github.com/mydumper/mydumper/releases/download/${release}/mydumper-${release:1}.el7.x86_64.rpm

yum install https://github.com/mydumper/mydumper/releases/download/${release}/mydumper-${release:1}.el8.x86_64.rpm

```



### Ubuntu / Debian

For ubuntu, you need to install the dependencies:

```bash

apt-get install libatomic1

```

Then you can download and install the package:

```bash

release=$(curl -Ls -o /dev/null -w %{url_effective} https://github.com/mydumper/mydumper/releases/latest | cut -d'/' -f8)

wget https://github.com/mydumper/mydumper/releases/download/${release}/mydumper_${release:1}.$(lsb_release -cs)_amd64.deb

dpkg -i mydumper_${release:1}.$(lsb_release -cs)_amd64.deb

```



### FreeBSD

By using pkg



```bash

pkg install mydumper

```

or from ports



```bash

cd /usr/ports/databases/mydumper && make install

```



### MacOS

By using [Homebrew](https://brew.sh/)



```bash

brew install mydumper

```

Take into account that the mydumper.cnf file is going to be located on /usr/local/etc or /opt/homebrew/etc.

So, you might need to run mydumper/myloader with:

```bash

mydumper --defaults-file=/opt/homebrew/etc/mydumper.cnf

myloader --defaults-file=/opt/homebrew/etc/mydumper.cnf

```



## Dependencies for building MyDumper



### Install development tools:

* Ubuntu or Debian:

```shell

apt-get install cmake g++ git

```

* Fedora, RedHat and CentOS:

```shell

yum install -y cmake gcc gcc-c++ git make

```

* MacOS <= 10.13 (High Sierra) < 13 (Ventura) with MacPorts package manager:



```shell

sudo port install cmake pkgconfig

```

### Install development versions of GLib, ZLib, PCRE and ZSTD:

* Ubuntu or Debian:

```shell

apt-get install libglib2.0-dev zlib1g-dev libpcre3-dev libssl-dev libzstd-dev

```

* Fedora, RedHat and CentOS:

```shell

yum install -y glib2-devel openssl-devel pcre-devel zlib-devel libzstd-devel

```

* openSUSE:

```shell

zypper install glib2-devel libmysqlclient-devel pcre-devel zlib-devel

```

* MacOS <= 10.13 (High Sierra) < 13 (Ventura) with MacPorts package manager:

```shell

sudo port install glib2 pcre

```

### Install MySQL/Percona/MariaDB development versions:

You need to select one vendor development library.

* Ubuntu or Debian:

```shell

apt-get install libmysqlclient-dev

apt-get install libperconaserverclient20-dev

apt-get install libmariadbclient-dev

```

* Fedora, RedHat and CentOS:

```shell

yum install -y mysql-devel

yum install -y Percona-Server-devel-57

yum install -y mariadb-devel

```

CentOS 7 comes by default with MariaDB 5.5 libraries which are very old.

  It might be better to download a newer version of these libraries (MariaDB, MySQL, Percona etc).

* openSUSE:

```shell

zypper install libmysqlclient-devel

```



* MacOS <= 10.13 (High Sierra) < 13 (Ventura) with MacPorts package manager

``` shell

sudo port install mariadb-10.11

sudo port select mysql

```

## How to Build



Run:



```shell

cmake .

make

sudo make install

```



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



To build against mysql libs < 5.7 you need to disable SSL adding -DWITH_SSL=OFF



### Build Docker image

You can download the [official docker image](https://hub.docker.com/r/mydumper/mydumper) or you can build the Docker image either from local sources or directly from Github sources with [the provided Dockerfile](./Dockerfile).

```shell

docker build --build-arg CMAKE_ARGS='-DWITH_ZSTD=ON' -t mydumper github.com/mydumper/mydumper

```

Keep in mind that the main purpose the Dockerfile addresses is development and build from source locally. It might not be optimal for distribution purposes, but can also work as a quick build and run solution with the above one-liner, though.



# How to use MyDumper



See [Usage](docs/mydumper_usage.rst)



## 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 read 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 a 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 :)



## How to exclude (or include) databases?



Once can use --regex functionality, for example not to dump mysql, sys and test databases:



```bash

 mydumper --regex '^(?!(mysql\.|sys\.|test\.))'

```



To dump only mysql and test databases:



```bash

 mydumper --regex '^(mysql\.|test\.)'

```



To not dump all databases starting with test:



```bash

 mydumper --regex '^(?!(test))'

```



To dump specific tables in different databases (Note: The name of tables should end with $. [related issue](https://github.com/maxbube/mydumper/issues/407)):



```bash

 mydumper --regex '^(db1\.table1$|db2\.table2$)'

```



If you want to dump a couple of databases but discard some tables, you can do:

```bash

 mydumper --regex '^(?=(?:(db1\.|db2\.)))(?!(?:(db1\.table1$|db2\.table2$)))'

```

Which will dump all the tables in db1 and db2 but it will exclude db1.table1 and db2.table2



Of course, regex functionality can be used to describe pretty much any list of tables.



## How to use --exec?



You can execute external commands with --exec like this:



```bash

 mydumper --exec "/usr/bin/gzip FILENAME"

```



--exec is single threaded, similar implementation than Stream. The exec program must be an absolute path. FILENAME will be replaced by the filename that you want to be processed. You can set FILENAME in any place as an argument.



## Defaults file



The default file (aka: --defaults-file parameter) is starting to be more important in MyDumper

- mydumper and myloader sections:



```bash

[mydumper]

host = 127.0.0.1

user = root

password = p455w0rd

database = db

rows = 10000



[myloader]

host = 127.0.0.1

user = root

password = p455w0rd

database = new_db

innodb-optimize-keys = AFTER_IMPORT_PER_TABLE

```



- Variables for mydumper and myloader executions:



Prior to v0.14.0-1:

```bash

[mydumper_variables]

wait_timeout = 300

sql_mode = ONLY_FULL_GROUP_BY,STRICT_TRANS_TABLES,ERROR_FOR_DIVISION_BY_ZERO,NO_ENGINE_SUBSTITUTION



[myloader_variables]

long_query_time = 300

innodb_flush_log_at_trx_commit = 0

```

From to v0.14.0-1:

```bash

[mydumper_session_variables]

wait_timeout = 300

sql_mode = ONLY_FULL_GROUP_BY,STRICT_TRANS_TABLES,ERROR_FOR_DIVISION_BY_ZERO,NO_ENGINE_SUBSTITUTION



[mydumper_global_variables]

sync_binlog = 0

slow_query_log = OFF



[myloader_session_variables]

long_query_time = 300



[myloader_global_variables]

sync_binlog = 0

innodb_flush_log_at_trx_commit = 0

```



- Per table sections:

```bash

[`db`.`table`]

where = column > 20

limit = 10000



[`myd_test`.`t`]

columns_on_select=qty,price+20

columns_on_insert=qty,price

```



IMPORTANT: when using options that don't require an argument like: --no-data or --events, you need to set any value to those variables which will always indicate: TRUE/ON/ENABLE. It is a MISCONCEPTION if you think that adding `--no-data=0` will export data:

```

[mydumper]

no-data=0

```

Will NOT export the data as no-data is being specified.