The diskspace_* tables store diskspace metrics.
- diskspace_now is an external table whose data files are stored in $MASTER_DATA_DIRECTORY/gpperfmon/data. Current diskspace metrics are stored in database_now during the period between data collection from the Command Center agents and automatic commitment to the diskspace_history table.
- diskspace_tail is an external table whose data files are stored in $MASTER_DATA_DIRECTORY/gpperfmon/data. This is a transitional table for diskspace metrics that have been cleared from diskspace_now but has not yet been committed to diskspace_history. It typically only contains a few minutes worth of data.
- diskspace_history is a regular table that stores historical diskspace 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.
|ctime||timestamp(0) without time zone||Time of diskspace measurement.|
|hostname||varchar(64)||The hostname associated with the diskspace measurement.|
|Filesystem||text||Name of the filesystem for the diskspace measurement.|
|total_bytes||bigint||Total bytes in the file system.|
|bytes_used||bigint||Total bytes used in the file system.|
|bytes_available||bigint||Total bytes available in file system.|