Percona is happy to announce the experimental release of Percona XtraDB Cluster 8.0. This is a major step for tuning Percona XtraDB Cluster to be more cloud- and user-friendly. This is the second experimental release that combines the updated and feature-rich Galera 4, with substantial improvements made by our development team.
Improvements and New Features in Percona XtraDB Cluster
Galera 4, included in Percona XtraDB Cluster 8.0, has many new features. Here is a list of the most essential improvements:
- Streaming replication to support large transactions
- The synchronization functions allow action coordination (wsrep_last_seen_gtid, wsrep_last_written_gtid, wsrep_sync_wait_upto_gtid)
- More granular and improved error logging. wsrep_debug is now a multi-valued variable to assist in controlling the logging, and logging messages have been significantly improved.
- Some DML and DDL errors on a replicating node can either be ignored or suppressed. Use the wsrep_ignore_apply_errors variable to configure.
- Multiple system tables help find out more about the state of the cluster state.
- The wsrep infrastructure of Galera 4 is more robust than that of Galera 3. It features a faster execution of code with better state handling, improved predictability, and error handling.
Percona XtraDB Cluster 8.0 has been reworked in order to improve security and reliability as well as to provide more information about your cluster:
- There is no need to create a backup user or maintain the credentials in plain text (a security flaw). An internal SST user is created, with a random password for making a backup, and this user is discarded immediately once the backup is done.
- Percona XtraDB Cluster 8.0 now automatically launches the upgrade as needed (even for minor releases). This avoids manual intervention and simplifies the operation in the cloud.
- SST (State Snapshot Transfer) rolls back or fixes an unwanted action. It is no more “a copy only block” but a smart operation to make the best use of the copy-phase.
- Additional visibility statistics introduced in order to obtain more information about Galera internal objects. This enables easy tracking of the state of execution and flow control.
You can install this release by using the percona-release tool. Since this is an experimental release and not a GA release, you need to enable the experimental repository and then install Percona XtraDB Cluster 8.0 using your package management system, such as
yum. Note that this release is not ready for use in any production environment.
$ sudo percona-release enable-only pxc-80 experimental
$ sudo percona-release enable tools release
If you use the apt package manager, use the following steps:
$ sudo apt update
$ sudo apt install percona-xtradb-cluster-full
If you use the yum package manager, install Percona XtraDB Cluster 8.0 as follows:
$ sudo yum update
$ sudo yum install percona-xtradb-cluster-full
Percona XtraDB Cluster 8.0 is based on the following:
- Percona Server for MySQL 8.0.18-9
- Codership WSREP API release 26
- Codership Galera library 4.3
and also includes:
- Percona XtraBackup 8.0.9 as well as Percona XtraBackup 2.4.18 (to facilitate migrations from PXC 5.7)
Please be aware that this release will not be supported in the future, and as such, neither the upgrade to this release nor the downgrade from higher versions is supported.
- PXC-2994: 8.0 clone plugin doesn’t work for cloning remote data
- PXC-2999: DML commands are not replicating to PXC-8.0 nodes through MySQL shell
- PXC-3016: 8.0 set persist binlog_format=’STATEMENT’ should not succeed
- PXC-3020: Cluster goes down if a node is restarted during load
- PXC-3027: Global wsrep memory leaks
- PXC-3028: Memory leaks inside wsrep_st
- PXC-3039: No useful error messages if an SSL-disabled node tries to join SSL-enabled cluster
- PXC-3047: hung if cannot connect to members PXC 8.0
Help us improve our software quality by reporting any bugs you encounter using our bug tracking system. As always, thank you for your input and for your continued support of Percona!