Percona XtraDB Cluster 5.7.17-27.20 发布了，二进制文件可在 下载区 或 软件仓库 中下载。（注意：你也可以从 Docker Hub 仓库中的镜像运行 Docker 容器）
Percona XtraDB Cluster 5.7.17-27.20 基于以下这些项目：
- Percona Server 5.7.18-15
- Galera Replication library 3.20
- wsrep API version 2
该版本除了上游更改和相关包的修复外，对主要组件没有新功能或错误修复：
- PXC-749: Fixed memory leak when running INSERT on a table without primary key defined and wsrep_certify_nonPK disabled (set to 0).
- NOTE: We recommend you define primary keys on all tables for correct write-set replication.
- PXC-812: Fixed SST script to leave the DONOR keyring when JOINER clears the datadir.
- PXC-813: Fixed SST script to use UTC time format.
- PXC-816: Fixed hook for caching GTID events in asynchronous replication. For more information, see #1681831.
- PXC-820: Enabled querying of pxc_maint_mode by another client during the transition period.
- PXC-823: Fixed SST flow to gracefully shut down JOINER node if SST fails because DONOR leaves the cluster due to network failure. This ensures that the DONOR is then able to recover to synced state when network connectivity is restored For more information, see #1684810.
- PXC-824: Fixed graceful shutdown of Percona XtraDB Cluster node to wait until applier thread finishes.
