The document introduces MySQL Clone, a plugin that provides a simple way to create a replica of a MySQL instance. It allows cloning data locally or remotely from a "donor" server to a "recipient" server. The cloning process happens in stages, copying data files, page IDs, and redo logs to keep the recipient synchronized. Monitoring can be done via the performance_schema to check the clone's progress and status. Variables control resources used and networking during the clone operation. It is intended to provision new replication nodes and re-provision returning nodes.

2. Safe harbor statement
The following is intended to outline our general product direction. It is intended for information purposes
only, and may not be incorporated into any contract. It is not a commitment to deliver any material,
code, or functionality, and should not be relied upon in making purchasing decisions.
The development, release, timing, and pricing of any features or functionality described for Oracle’s
products may change and remains at the sole discretion of Oracle Corporation.
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3. What is MySQL Clone ?
A simple and efficient way to create
a MySQL instance replica
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4. WhyYet Another Method ?
• It’s easy to use: a single command
• It’s a data snapshot with consistent GTID and binary log position
• Data can be cloned locally or from remote
• It’s resumable !
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5. It’s FASTER Too !
5
https://mydbops.wordpress.com/2019/11/14/
mysql-clone-plugin-speed-test/
2 servers
CPU: 2 Cores
RAM: 4 GB
DISK: 200 GB SSD
approx. 122.40 GB data from sysbench
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6. Clone: Use Cases
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7. Provision a new replication node
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Master
Slave
Slave 2

8. Re-provision a returning node
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BinlogMaster SlaveData ??

9. Clone: Operation
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10. Terminology
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Donor RecipientData

11. The big picture
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Client Network
Network
Clone
Plugin
Innodb
SE-2
[Future]
Clone
Plugin
Innodb
SE-2
[Future]
Recipient
Server
Donor
Server
Clone SQL
mysql> CLONE INSTANCE
FROM
clone_user@donor.host.com:3306
IDENTIFIED BY
"clone_password";
Connect

12. Prerequisites on the Donor
• Install the plugin:
INSTALL PLUGIN clone SONAME 'mysql_clone.so';
• Grant BACKUP_ADMIN to a user account
CREATE USER foo …;
GRANT BACKUP_ADMIN TO foo;
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13. Prerequisites on the Recipient
• Install the plugin:
INSTALL PLUGIN clone SONAME 'mysql_clone.so';
• Grant CLONE_ADMIN to a user account
CREATE USER bar …;
GRANT CLONE_ADMIN TO bar;
• Allow the donor host
SET GLOBAL clone_valid_donor_list='donor_computer:3306';
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14. On the recipient, as “bar”
CLONE INSTANCE FROM foo@donor_computer:3306
IDENTIFIED BY 'foo_pwd‘
DATA DIRECTORY = 'clone_dir'
REQUIRE SSL
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15. Clone: What Has Just Happened ?
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16. Clone Stages
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Init
Data
Files
File Copy
Modified
Page IDs
Page Copy
Redo
Logs
Redo Copy Done

17. Clone: Network Failure Recovery
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Donor RecipientData
Less than 5 min

18. Clone Monitoring: performance_schema.clone_status
mysql> SELECT STATE FROM performance_schema.clone_status;
+-----------+
| STATE |
+-----------+
| Completed |
+-----------+
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19. Clone Monitoring: performance_schema.clone_progress
mysql> SELECT STAGE, STATE, END_TIME FROM performance_schema.clone_progress;
+-----------+-----------+----------------------------+
| stage | state | end_time |
+-----------+-----------+----------------------------+
| DROP DATA | Completed | 2019-10-27 14:45:43.141261 |
| FILE COPY | Completed | 2019-10-27 14:45:44.457572 |
| PAGE COPY | Completed | 2019-10-27 14:45:44.577330 |
| REDO COPY | Completed | 2019-10-27 14:45:44.679570 |
| FILE SYNC | Completed | 2019-10-27 14:45:44.918547 |
| RESTART | Completed | 2019-10-27 14:45:48.583565 |
| RECOVERY | Completed | 2019-10-27 14:45:49.626595 |
+-----------+-----------+----------------------------+
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20. Performance And Resource Use Control
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Variable Type Meaning
clone_max_concurrency Int (Maximum) number of cloning threads
clone_autotune_concurrency Bool Enable dynamic spawning of cloning threads
clone_max_network_bandwidth Int,
Mbps
(recipient only) limit network usage
clone_max_data_bandwidth Int,
Mbps
(recipient only) limit clone transfer rate

21. Clone Limitations
• Does not clone configuration values
• Does not clone binary logs
• Supports only InnoDB
• Blocks all concurrent DDLs on the Donor
• Will FULLY override recipient data
• Cloning can be done only to the SAME server version
• Doesn’t work over the X protocol
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22. Further Reading
• Reference Manual
• https://dev.mysql.com/doc/refman/8.0/en/clone-plugin.html
• Blogs
• https://mysqlserverteam.com/clone-create-mysql-instance-replica/
• https://mysqlhighavailability.com/mysql-innodb-cluster-automatic-node-provisioning
• https://mysqlhighavailability.com/a-breakthrough-in-usability-automatic-node-provisioning
• https://mysqlhighavailability.com/automatic-provisioning-in-group-replication
• InnoDB cluster video
• https://lefred.be/content/migrate-from-a-single-mysql-instance-to-mysql-innodb-cluster-
using-clone-plugin/
© 2020 Oracle22

23. Thank you !
Georgi Kodinov, Software Development Director
Georgi.Kodinov@oracle.com
https://www.slideshare.net/GeorgiKodinov
© 2020 Oracle23