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Percona XtraDB Cluster
About Percona XtraDB Cluster
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    • Home
      • About Percona XtraDB Cluster
        • Benefits
        • Drawbacks
        • Components
      • Percona XtraDB Cluster limitations
      • Understand version numbers
      • Quick start guide for Percona XtraDB Cluster
      • Install Percona XtraDB Cluster
      • Configure nodes for write-set replication
      • Bootstrap the first node
      • Add nodes to cluster
      • Verify replication
      • High availability
      • PXC strict mode
      • Online schema upgrade
      • Non-Blocking Operations (NBO) method for Online Scheme Upgrades (OSU)
      • Security basics
      • Secure the network
      • Encrypt PXC traffic
      • Enable AppArmor
      • Enable SELinux
      • State snapshot transfer
      • Percona XtraBackup SST configuration
      • Restart the cluster nodes
      • Cluster failover
      • Monitor the cluster
      • Certification in Percona XtraDB Cluster
      • Percona XtraDB Cluster threading model
      • Understand GCache and Record-Set cache
      • GCache encryption and Write-Set cache encryption
      • Perfomance Schema instrumentation
      • Data at Rest Encryption
      • Upgrade Percona XtraDB Cluster
      • Crash recovery
      • Configure Percona XtraDB Cluster on CentOS
      • Configure Percona XtraDB Cluster on Ubuntu
      • Set up Galera arbitrator
      • How to set up a three-node cluster on a single box
      • How to set up a three-node cluster in EC2 environment
      • Load balancing with HAProxy
      • Load balancing with ProxySQL
      • ProxySQL admin utilities
      • Setting up a testing environment with ProxySQL
      • Release notes index
      • Percona XtraDB Cluster 8.0.31-23 (2023-03-14)
      • Percona XtraDB Cluster 8.0.30-22.md (2022-12-28)
      • Percona XtraDB Cluster 8.0.29-21 (2022-09-12)
      • Percona XtraDB Cluster 8.0.28-19.1 (2022-07-19)
      • Percona XtraDB Cluster 8.0.27-18.1
      • Percona XtraDB Cluster 8.0.26-16.1
      • Percona XtraDB Cluster 8.0.25-15.1
      • Percona XtraDB Cluster 8.0.23-14.1
      • Percona XtraDB Cluster 8.0.22-13.1
      • Percona XtraDB Cluster 8.0.21-12.1
      • Percona XtraDB Cluster 8.0.20-11
      • Percona XtraDB Cluster 8.0.20-11.3
      • Percona XtraDB Cluster 8.0.20-11.2
      • Percona XtraDB Cluster 8.0.19-10
      • Percona XtraDB Cluster 8.0.18-9.3
      • Index of wsrep status variables
      • Index of wsrep system variables
      • Index of wsrep_provider options
      • Index of files created by PXC
      • Frequently asked questions
      • Glossary
      • Copyright and licensing information
      • Trademark policy

    • Benefits
    • Drawbacks
    • Components

    About Percona XtraDB Cluster¶

    Percona XtraDB Cluster is a fully open-source high-availability solution for MySQL. It integrates Percona Server for MySQL and Percona XtraBackup with the Galera library to enable synchronous multi-source replication.

    A cluster consists of nodes, where each node contains the same set of data synchronized accross nodes. The recommended configuration is to have at least 3 nodes, but you can have 2 nodes as well. Each node is a regular MySQL Server instance (for example, Percona Server). You can convert an existing MySQL Server instance to a node and run the cluster using this node as a base. You can also detach any node from the cluster and use it as a regular MySQL Server instance.

    image

    Benefits¶

    • When you execute a query, it is executed locally on the node. All data is available locally, no need for remote access.

    • No central management. You can loose any node at any point of time, and the cluster will continue to function without any data loss.

    • Good solution for scaling a read workload. You can put read queries to any of the nodes.

    Drawbacks¶

    • Overhead of provisioning new node. When you add a new node, it has to copy the full data set from one of existing nodes. If it is 100 GB, it copies 100 GB.

    • This can’t be used as an effective write scaling solution. There might be some improvements in write throughput when you run write traffic to 2 nodes versus all traffic to 1 node, but you can’t expect a lot. All writes still have to go on all nodes.

    • You have several duplicates of data: for 3 nodes you have 3 duplicates.

    Components¶

    Percona XtraDB Cluster https://www.percona.com/software/mysql-database/percona-xtradb-cluster is based on Percona Server for MySQL running with the XtraDB storage engine. It uses the Galera library, which is an implementation of the write set replication (wsrep) API developed by Codership Oy. The default and recommended data transfer method is via Percona XtraBackup .

    Contact us

    For free technical help, visit the Percona Community Forum.

    To report bugs or submit feature requests, open a JIRA ticket.

    For paid support and managed or consulting services , contact Percona Sales.


    Last update: 2022-08-16
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