https://dev.mysql.com/group-replication-frequently-asked-questions.html
Warning When the network round-trip time (RTT) between any group members is 5 seconds or more you could encounter problems as the built-in failure detection mechanism could be incorrectly triggered. From MySQL 8.0, you can activate two settings to ...Attempting to add another server to a group with 9 members causes the request to join to be ...
https://dev.mysql.com/group-replication-limitations.html
To avoid these issues use the following mitigations: If unnecessary expulsions occur due to large messages, use the system variable group_replication_member_expel_timeout to allow additional time before a member under suspicion of having failed is ...Note that the limitations and issues described for multi-primary mode groups can also apply in single-primary mode clusters during a failover event, while the newly elected primary flushes out its applier queue from the old ...
https://dev.mysql.com/group-replication-network-partitioning.html
For example, in the above scenario of 5 servers where 3 leave at once, if the 3 leaving servers warn the group that they are leaving, one by one, then the membership is able to adjust itself from 5 to 2, and at the same time, securing quorum while ... The group needs to achieve consensus whenever a change that needs to be replicated ...
https://dev.mysql.com/group-replication-responses-failure.html
When a suspicion times out, the suspected member is assumed to have failed, and is expelled from the group. By default, the following behaviors happen if a member is suspected of having failed: When a suspicion is created, it times out immediately ... Group Replication's failure detection mechanism is designed to identify group members that are no longer communicating with the group, and expel them as and when it seems likely that they have ...
https://dev.mysql.com/group-replication-upgrading-member.html
Note The longer it takes to upgrade a server, the more time that member is offline and therefore the more time it takes for the server to catch up when added back to the group. This section explains the steps required for upgrading a member of a ...
https://dev.mysql.com/group-replication.html
Groups can operate in a single-primary mode with automatic primary election, where only one server accepts updates at a time. There is a built-in group membership service that keeps the view of the group consistent and available for all servers at ... This chapter explains MySQL Group Replication and how to install, configure and monitor ...
https://dev.mysql.com/host-cache.html
(In this case, another DNS resolution attempt occurs the next time a client connects from this IP.) If an error occurs while processing an incoming client connection from a given IP address, the server updates the corresponding error counters in the ... The MySQL server maintains a host cache in memory that contains information about clients: IP address, host name, and error ...
https://dev.mysql.com/ibd2sdi.html
ibd2sdi can be used at runtime or while the server is offline. During DDL operations, ROLLBACK operations, and undo log purge operations related to SDI, there may be a short interval of time when ibd2sdi fails to read SDI data stored in the ...
https://dev.mysql.com/index-condition-pushdown-optimization.html
ICP can reduce the number of times the storage engine must access the base table and the number of times the MySQL server must access the storage engine. Index Condition Pushdown (ICP) is an optimization for the case where MySQL retrieves rows from ...
https://dev.mysql.com/innodb-benefits.html
You may find InnoDB tables beneficial for the following reasons: If your server crashes because of a hardware or software issue, regardless of what was happening in the database at the time, you don't need to do anything special after restarting ...
