The socket_stats_* tables store statistical metrics about socket usage for a Greenplum Database instance. There are three system tables, all having the same columns:

    These tables are in place for future use and are not currently populated.

    • socket_stats_now is an external table whose data files are stored in $MASTER_DATA_DIRECTORY/gpperfmon/data.
    • socket_stats_tail is an external table whose data files are stored in $MASTER_DATA_DIRECTORY/gpperfmon/data. This is a transitional table for socket statistical metrics that has been cleared from socket_stats_now but has not yet been committed to socket_stats_history. It typically only contains a few minutes worth of data.
    • socket_stats_history is a regular table that stores historical socket statistical metrics. It is pre-partitioned into monthly partitions. Partitions are automatically added in two month increments as needed.
    Column Type Description
    total_sockets_used int Total sockets used in the system.
    tcp_sockets_inuse int Number of TCP sockets in use.
    tcp_sockets_orphan int Number of TCP sockets orphaned.
    tcp_sockets_timewait int Number of TCP sockets in Time-Wait.
    tcp_sockets_alloc int Number of TCP sockets allocated.
    tcp_sockets_memusage_inbytes int Amount of memory consumed by TCP sockets.
    udp_sockets_inuse int Number of UDP sockets in use.
    udp_sockets_memusage_inbytes int Amount of memory consumed by UDP sockets.
    raw_sockets_inuse int Number of RAW sockets in use.
    frag_sockets_inuse int Number of FRAG sockets in use.
    frag_sockets_memusage_inbytes int Amount of memory consumed by FRAG sockets.

    Parent topic: The gpperfmon Database