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. Administrators must drop old partitions for the months that are no longer needed.
|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.|