RESOURCE_REJECTIONS

Monitors requests for resources that are rejected by the Resource Manager. Information is valid only as long as the node is up and the counters reset to 0 upon node restart.

 Column Name Data Type Description 
NODE_NAME

VARCHAR

The node name for which information is listed.

 
POOL_ID

INTEGER

Catalog-assigned integer value that uniquely identifies the resource pool.

 
POOL_NAME

VARCHAR

The name of the resource pool.

 
REASON

VARCHAR

The reason for rejecting this request; for example:

  • Usage of single request exceeds high limit
  • Timed out waiting for resource reservation
  • Canceled waiting for resource reservation
 
RESOURCE_TYPE

VARCHAR

Memory, threads, file handles or execution slots.

The following list shows the resources that are limited by the resource manager. A query might need some amount of each resource, and if the amount needed is not available, the query is queued and could eventually time out of the queue and be rejected.

  • Number of running plans
  • Number of running plans on initiator node (local)
  • Number of requested threads
  • Number of requested file handles
  • Number of requested KB of memory
  • Number of requested KB of address space

Execution slots are determined by MAXCONCURRENCY parameter.

 
REJECTION_COUNT

INTEGER

Number of requests rejected due to specified reason and RESOURCE_TYPE.

 
FIRST_REJECTED_TIMESTAMP

TIMESTAMPTZ

The time of the first Closedrejection for this pool

Reasons for Rejection

  • Usage of single request exceeds high limit
  • Timed out waiting for resource reservation
  • Canceled waiting for resource reservation
 
LAST_REJECTED_TIMESTAMP

TIMESTAMPTZ

The time of the last rejection for this pool 

LAST_REJECTED_VALUE

INTEGER

The amount of the specific resource requested by the last rejection

Example

=> SELECT node_name, pool_name, reason, resource_type,
   rejection_count AS count,
   last_rejected_value AS value
   FROM resource_rejections;
node_name |  pool_name  |                reason                 |   resource_type   | count |       value
-----------+-------------+---------------------------------------+-------------------+---------------------------
initiator | alsohassome | Request exceeded high limit           | Memory(KB)        |  1    |            102400
initiator | ceo         | Timedout waiting for resource request | Memory(KB)        |  1    |            102400
initiator | empty       | Request exceeded high limit           | Queries           |  1    |                 1
initiator | general     | Request exceeded high limit           | Address space(KB) |  2    | 45035996273704970
initiator | general     | Request exceeded high limit           | Memory(KB)        | 24    |           8395584
initiator | sa          | Request exceeded high limit           | Memory(KB)        |  3    |            102400
initiator | sa          | Timedout waiting for resource request | Memory(KB)        |  1    |                10
initiator | small       | Request exceeded high limit           | Memory(KB)        | 26    |            102400
initiator | small       | Timedout waiting for resource request | Memory(KB)        |  2    |            122880
initiator | sysdata     | Request exceeded high limit           | Memory(KB)        |  5    |            102400
(10 rows)

The following command returns the type of resources currently running on the node:

=> SELECT resource_type FROM resource_rejections;
 resource_type
---------------
 UPDATE_QUERY
 UPDATE_QUERY
 UPDATE_QUERY
(3 rows)

See Also