User Resource Monitoring

Context

In the multi-tenant management framework, you can query the real-time or historical usage of all user resources (including memory, CPU cores, storage space, temporary space, and I/Os).

• User real-time resource views/functions: PG_TOTAL_USER_RESOURCE_INFO and GS_WLM_USER_RESOURCE_INFO; user historical resource table: GS_WLM_USER_RESOURCE_HISTORY.
• You can monitor the CPU, I/O, and memory usage of all jobs on the fast and slow lanes.
• Currently, the memory and CPU usage of fast track jobs are not controlled. When the fast lane jobs occupy a large number of resources, the used resources may exceed the resource limit.
• In the DN monitoring view, I/O, memory, and CPU display the resource usage and limits of resource pools.
• In the CN monitoring view, I/O, memory, and CPU display the total resource usage and limit of all DN resource pools in the cluster.
• The DN monitoring information is updated every 5 seconds. CNs collect monitoring information from DNs every 5 seconds. Because each instance updates or collects user monitoring information independently, the monitoring information update time on each instance may be different.
• The auxiliary thread automatically invokes the persistence function every 30 seconds to make user monitoring data persistent. So, normally, you don't have to do this.
• When there are a large number of users and a large cluster, querying such real-time views will cause network latency due to the real-time communication overhead between CNs and DNs.
• Resources are not monitored for an initial administrator.

Procedure

• Query all users' resource quotas and real-time resource usage.

  1	SELECT * FROM PG_TOTAL_USER_RESOURCE_INFO;

  The result view is as follows:

  username        | used_memory | total_memory | used_cpu | total_cpu | used_space | total_space | used_temp_space | total_temp_space | used_spill_space | total_spill_space | read_kbytes | write_kbytes | read_counts | write_counts | read_speed | write_speed
  -----------------------+-------------+--------------+----------+-----------+------------+-------------+-----------------+------------------+------------------+-------------------+-------------+--------------+-------------+--------------+------------+-------------
  perfadm               |           0 |            0 |        0 |         0 |          0 |          -1 |               0 |               -1 |                0 |                -1 |           0 |            0 |           0 |            0 |          0 |           0
  usern                 |           0 |        17250 |        0 |        48 |          0 |          -1 |               0 |               -1 |                0 |                -1 |           0 |            0 |           0 |            0 |          0 |           0
  userg                 |          34 |        15525 |    23.53 |        48 |          0 |          -1 |               0 |               -1 |        814955731 |                -1 |     6111952 |      1145864 |      763994 |       143233 |      42678 |        8001
  userg1                |          34 |        13972 |    23.53 |        48 |          0 |          -1 |               0 |               -1 |        814972419 |                -1 |     6111952 |      1145864 |      763994 |       143233 |      42710 |        8007
  (4 rows)

  The I/O resource monitoring fields (read_kbytes, write_kbytes, read_counts, write_counts, read_speed, and write_speed) can be available only when the GUC parameter enable_user_metric_persistent is enabled.

  For details about each column, see PG_TOTAL_USER_RESOURCE_INFO.

• Query a user's resource quota and real-time resource usage.

  1	SELECT * FROM GS_WLM_USER_RESOURCE_INFO('username');

  The query result is as follows:

  userid | used_memory | total_memory | used_cpu | total_cpu | used_space | total_space | used_temp_space | total_temp_space | used_spill_space | total_spill_space | read_kbytes | write_kbytes | read_counts | write_counts | read_speed | write_speed
  --------+-------------+--------------+----------+-----------+------------+-------------+-----------------+------------------+------------------+-------------------+-------------+--------------+-------------+--------------+------------+-------------
  16407 |           18 |        1655 |        6 |         19 |          13787176 |          -1 |               0 |               -1 |                0 |                -1 |           0 |            0 |           0 |            0 |          0 |           0
  (1 row)

• Query all users' resource quotas and historical resource usage.

  1	SELECT * FROM GS_WLM_USER_RESOURCE_HISTORY;

  The query result is as follows:

  username        |           timestamp           | used_memory | total_memory | used_cpu | total_cpu | used_space | total_space | used_temp_space | total_temp_space | used_spill_space | total_spill_space | read_kbytes | write_kbytes | read_counts | write_counts | read_speed  | write_speed
  -----------------------+-------------------------------+-------------+--------------+----------+-----------+------------+-------------+-----------------+------------------+------------------+-------------------+-------------+--------------+-------------+--------------+-------------+-------------
  usern                 | 2020-01-08 22:56:06.456855+08 |           0 |        17250 |        0 |        48 |          0 |          -1 |               0 |               -1 |         88349078 |                -1 |       45680 |           34 |        5710 |            8 |         320 |           0
  userg                 | 2020-01-08 22:56:06.458659+08 |           0 |        15525 |    33.48 |        48 |          0 |          -1 |               0 |               -1 |        110169581 |                -1 |       17648 |           23 |        2206 |            5 |         123 |           0
  userg1                | 2020-01-08 22:56:06.460252+08 |           0 |        13972 |    33.48 |        48 |          0 |          -1 |               0 |               -1 |        136106277 |                -1 |       17648 |           23 |        2206 |            5 |         123 |           0

  For the system catalog in GS_WLM_USER_RESOURCE_HISTORY, data in the PG_TOTAL_USER_RESOURCE_INFO view is periodically saved to historical tables only when the GUC parameter enable_user_metric_persistent is enabled.

  For details about each column, see GS_WLM_USER_RESOURCE_HISTORY.