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29.12.20.9 Socket Summary Tables

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

  • socket_summary_by_event_name: Aggregate timer and byte count statistics generated by the wait/io/socket/* instruments for all socket I/O operations, per socket instrument.

  • socket_summary_by_instance: Aggregate timer and byte count statistics generated by the wait/io/socket/* instruments for all socket I/O operations, per socket instance. When a connection terminates, the row in socket_summary_by_instance corresponding to it is deleted.

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 29.12.20.1, “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:

  • COUNT_STAR, SUM_TIMER_WAIT, MIN_TIMER_WAIT, AVG_TIMER_WAIT, MAX_TIMER_WAIT

    These columns aggregate all operations.

  • COUNT_READ, SUM_TIMER_READ, MIN_TIMER_READ, AVG_TIMER_READ, MAX_TIMER_READ, SUM_NUMBER_OF_BYTES_READ

    These columns aggregate all receive operations (RECV, RECVFROM, and RECVMSG).

  • COUNT_WRITE, SUM_TIMER_WRITE, MIN_TIMER_WRITE, AVG_TIMER_WRITE, MAX_TIMER_WRITE, SUM_NUMBER_OF_BYTES_WRITE

    These columns aggregate all send operations (SEND, SENDTO, and SENDMSG).

  • COUNT_MISC, SUM_TIMER_MISC, MIN_TIMER_MISC, AVG_TIMER_MISC, MAX_TIMER_MISC

    These columns aggregate all other socket operations, such as CONNECT, LISTEN, ACCEPT, CLOSE, and SHUTDOWN. There are no byte counts for these operations.

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.

The socket summary tables have these indexes:

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