system_*
system_*
The system_* tables store system utilization metrics. There are three system tables, all having the same columns:
- system_now is an external table whose data files are stored in $MASTER_DATA_DIRECTORY/gpperfmon/data. Current system utilization data is stored in system_now during the period between data collection from the gpperfmon agents and automatic commitment to the system_history table.
- system_tail is an external table whose data files are stored in $MASTER_DATA_DIRECTORY/gpperfmon/data. This is a transitional table for system utilization data that has been cleared from system_now but has not yet been committed to system_history. It typically only contains a few minutes worth of data.
- system_history is a regular table that stores historical system utilization metrics. It is pre-partitioned into monthly partitions. Partitions are automatically added in two month increments as needed.
| Column | Type | Description |
|---|---|---|
| ctime | timestamp | Time this row was created. |
| hostname | varchar(64) | Segment or master hostname associated with these system metrics. |
| mem_total | bigint | Total system memory in Bytes for this host. |
| mem_used | bigint | Used system memory in Bytes for this host. |
| mem_actual_used | bigint | Used actual memory in Bytes for this host (not including the memory reserved for cache and buffers). |
| mem_actual_free | bigint | Free actual memory in Bytes for this host (not including the memory reserved for cache and buffers). |
| swap_total | bigint | Total swap space in Bytes for this host. |
| swap_used | bigint | Used swap space in Bytes for this host. |
| swap_page_in | bigint | Number of swap pages in. |
| swap_page_out | bigint | Number of swap pages out. |
| cpu_user | float | CPU usage by the Greenplum system user. |
| cpu_sys | float | CPU usage for this host. |
| cpu_idle | float | Idle CPU capacity at metric collection time. |
| load0 | float | CPU load average for the prior one-minute period. |
| load1 | float | CPU load average for the prior five-minute period. |
| load2 | float | CPU load average for the prior fifteen-minute period. |
| quantum | int | Interval between metric collection for this metric entry. |
| disk_ro_rate | bigint | Disk read operations per second. |
| disk_wo_rate | bigint | Disk write operations per second. |
| disk_rb_rate | bigint | Bytes per second for disk read operations. |
| disk_wb_rate | bigint | Bytes per second for disk write operations. |
| net_rp_rate | bigint | Packets per second on the system network for read operations. |
| net_wp_rate | bigint | Packets per second on the system network for write operations. |
| net_rb_rate | bigint | Bytes per second on the system network for read operations. |
| net_wb_rate | bigint | Bytes per second on the system network for write operations. |