复制组中的每个成员都会对组接收到的事务进行认证和应用。有关认证器和应用器过程的统计信息有助于了解应用队列的增长情况、发现了多少冲突、检查了多少事务、哪些事务已在所有地方提交，等等。Each member in a replication group certifies and applies transactions received by the group. Statistics regarding the certifier and applier procedures are useful to understand how the applier queue is growing, how many conflicts have been found, how many transactions were checked, which transactions are committed everywhere, and so on.

performance_schema.replication_group_member_stats 表提供与认证过程相关的组级信息，以及每个复制组成员接收和发起事务的统计信息。该信息在所有作为复制组成员的服务器实例之间共享，因此可以从任何成员查询所有组成员的信息。请注意，远程成员的统计信息刷新由 group_replication_flow_control_period 选项中指定的消息周期控制，因此这些统计信息可能与在发出查询的成员处本地收集的统计信息略有不同。要使用此表监控组复制成员，请执行以下语句：The performance_schema.replication_group_member_stats table provides group-level information related to the certification process, and also statistics for the transactions received and originated by each individual member of the replication group. The information is shared between all the server instances that are members of the replication group, so information on all the group members can be queried from any member. Note that refreshing of statistics for remote members is controlled by the message period specified in the group_replication_flow_control_period option, so these can differ slightly from the locally collected statistics for the member where the query is made. To use this table to monitor a Group Replication member, issue the following statement:

mysql> SELECT * FROM performance_schema.replication_group_member_stats\G

您也可以使用以下说明：You can also use the following statement:

mysql> TABLE performance_schema.replication_group_member_stats\G

这些列对于监控连接在组中的成员的性能非常重要。假设组中的某个成员在其队列中报告的事务数量始终比其他成员多。这意味着该成员存在延迟，无法跟上组中其他成员的更新。根据这些信息，您可以决定要么将该成员从组中移除，要么延迟处理组中其他成员的事务，以减少队列中的事务数量。这些信息还可以帮助您决定如何调整 Group Replication 插件的流控制，参见 第 20.7.2 节，“流控制”。These columns are important for monitoring the performance of the members connected in the group. Suppose that one of the group's members always reports a large number of transactions in its queue compared to other members. This means that the member is delayed and is not able to keep up to date with the other members of the group. Based on this information, you could decide to either remove the member from the group, or delay the processing of transactions on the other members of the group in order to reduce the number of queued transactions. This information can also help you to decide how to adjust the flow control of the Group Replication plugin, see Section 20.7.2, “Flow Control”.