Failure detection is a cornerstone of distributed systems as it determines which components are working properly or not, allowing it to tackle both network and host instabilities and failures. Like many other distributed systems, Group Replication (GR) requires a majority of correctly operating group members to work properly.…
Category Archives: Group Replication
On-demand primary election
Having a server acting as a primary with multiple secondaries is the most common setup when using Group Replication. Until now though, there was no way to change the current primary member while the group was running without causing some sort of disruption.…
Setting up MySQL Group Replication with MySQL Docker images
MySQL Group Replication (GR) is a MySQL Server plugin that enables you to create elastic, highly-available, fault-tolerant replication topologies. Groups can operate in a
single-primary mode with automatic primary election, where only one server accepts updates at a time. Alternatively, groups can be deployed in multi-primary mode, where all servers can accept updates, even if they are issued concurrently.…
Protecting your data – Part II: Preventing unwanted data changes on Group Replication members by asynchronous replication channels
Further to our earlier blog post about Fail-safe enhancements to Group Replication, where we discussed enhancements against data modification in members which are not ONLINE, we now present here additional changes to protect data from being accidentally modified by asynchronous replication channels.…
Performance Improvements in MySQL 8.0 Replication
MySQL 8.0 became Generally Available (GA) on April 19th, a great moment for us working on MySQL at Oracle. It is now a “fully grown adult” packed with new features, and improvements to existing features, as described here.
This blog post focuses on the impact of replication performance improvements that went into MySQL 8.0.…
Replication Features in MySQL 8.0.4
MySQL 8 second release candidate is out (MySQL 8.0.4). Besides fixes to replication issues we have also delivered a couple of enhancements in this release. Let me quickly summarize them.
- Additional instrumentation for Group Replication (WL#9856). We have instrumented mutexes and condition synchronization objects on the group communication library.
Group Replication Features backported to MySQL 5.7
We have brought further enhancement to MySQL Group Replication 5.7 release by backporting some most requested features to MySQL 5.7.20 release:
- Member weight for automatic primary election on failover
- Disallow writes after leaving the group
And to MySQL 5.7.19 release:
- Transaction savepoint support
Member weight for automatic primary election on failover
The Member weight for automatic primary election on failover feature will allow user to influence primary member election using a integer member weight value.…
Replication Features in MySQL 8.0.3
Great news! MySQL 8.0.3 is out and it is a release candidate. In the replication team we have been busy working on interesting new enhancements and also doing some clean up. Some of these new features are out in this release.…
Group Replication: Prioritise member for the Primary Member Election
In initial Group Replication release, 5.7.17, we included the Single-Primary Mode with automatic membership and fail-over features. The MySQL Server 8.0.2 release has brought further enhancement to Group Replication Single-Primary Mode that will allow users to influence primary member election using integer member weight value.…
Group Replication – Extending Group Replication performance_schema tables
In MySQL 8.0.2, users will see the additional columns in the existing Group Replication Performance Schema tables which will provide extended information about Group Replication. Now user can view role and MySQL version of each member of the group, which earlier required a complex set of query.…