MySQL 5.7 Reference Manual Including MySQL NDB Cluster 7.5 and NDB Cluster 7.6

25.12.15.8 Socket Summary Tables

These socket summary tables aggregate timer and byte count information for socket operations:

The socket summary tables do not aggregate waits generated by idle events while sockets are waiting for the next request from the client. For idle event aggregations, use the wait-event summary tables; see Section 25.12.15.1, “Wait Event Summary Tables”.

Each socket summary table has one or more grouping columns to indicate how the table aggregates events. Event names refer to names of event instruments in the setup_instruments table:

Each socket summary table has these summary columns containing aggregated values:

The socket_summary_by_instance table also has an EVENT_NAME column that indicates the class of the socket: client_connection, server_tcpip_socket, server_unix_socket. This column can be grouped on to isolate, for example, client activity from that of the server listening sockets.

TRUNCATE TABLE is permitted for socket summary tables. Except for events_statements_summary_by_digest, tt resets the summary columns to zero rather than removing rows.