Top tips to drive your MariaDB Galera Cluster performance with new features

Length: 56

MariaDB Server has built in Galera Cluster since the 10.0 releases, and plenty of joint engineering happens between Codership and MariaDB Corporation and the MariaDB Foundation.

Galera Cluster as you may already know is a synchronous multi-primary (multi-master) replication solution, that has automatic node provisioning, with parallel replication, no secondary lag, with built-in automatic conflict detection and handling, plus components to allow load balancing.

So where does MariaDB Galera Cluster stand out compared to the rest? Here are a few selected features that may pique your interest:
* Galera 4 is standard in MariaDB Galera Cluster since MariaDB Server 10.4. Note that Galera Cluster is built-into MariaDB Server.
* The mysql database contains new tables: wsrep_cluster, wsrep_cluster_members, wsrep_streaming_log, and wsrep_allowlist.
* Streaming replication allows replicating transactions of an unlimited size, i.e. greater than 2GB.
* GTID handling with Galera Cluster and MariaDB Server are synchronised, thus you have seamless replication of MariaDB GTIDs to other nodes in the cluster.
* wsrep_mode to help you replicate MyISAM, and Aria storage engines.
* You can migrate from unencrypted replication to TLS Galera communications without any downtime.
* A JSON interface for wsrep node state, including progress logging for State Snapshot Transfers (SSTs). This also includes the IP allowlist for Galera Cluster nodes that can make the requests (currently a unique feature to MariaDB Server).
* Rolling upgrades from MariaDB Server 10.4 to later, are supported.

There are plenty more, considering there are **enterprise only features** like the Blackbox for Galera troubleshooting, encrypting of the gcache, and more. While we are at it, we will also cover the MariaDB MaxScale features that are Galera Cluster specific.