Amazon Redshift will no longer support the creation of new Python UDFs starting November 1, 2025.
If you would like to use Python UDFs, create the UDFs prior to that date.
Existing Python UDFs will continue to function as normal. For more information, see the
blog post
STV_WLM_SERVICE_CLASS_CONFIG
Records the service class configurations for WLM.
STV_WLM_SERVICE_CLASS_CONFIG is visible only to superusers. For more information, see Visibility of data in system tables and views.
Table columns
| Column name | Data type | Description |
|---|---|---|
| service_class | integer | ID for the service class. For a list of service class IDs, see WLM service class IDs. |
| queueing_strategy | character(32) | Reserved for system use. |
| num_query_tasks | integer | Current actual concurrency level of the service
class. If num_query_tasks and
target_num_query_tasks are different, a dynamic WLM
transition is in process.
A value of -1 indicates that Auto WLM is configured. |
| target_num_query_tasks | integer | Concurrency level set by the most recent WLM configuration change. |
| evictable | character(8) | Reserved for system use. |
| eviction_threshold | bigint | Reserved for system use. |
| query_working_mem | integer | Current actual amount of working memory, in MB per
slot, per node, assigned to the service class. If
query_working_mem and
target_query_working_mem are different, a dynamic
WLM transition is in process.
A value of -1 indicates than Auto WLM is configured. |
| target_query_working_mem | integer | The amount of working memory, in MB per slot, per node, set by the most recent WLM configuration change. |
| min_step_mem | integer | Reserved for system use. |
| name | character(64) | The name of the service class. |
| max_execution_time | bigint | Number of milliseconds that the query can run before being terminated. |
| user_group_wild_card | Boolean | If TRUE, the WLM queue treats an
asterisk (*) as a wildcard character in user group strings in the
WLM configuration. |
| query_group_wild_card | Boolean | If TRUE, the WLM queue treats an
asterisk (*) as a wildcard character in query group strings in the
WLM configuration. |
| concurrency_scaling | character(20) | Describes if the concurrency scaling is on or off. |
| query_priority | character(20) | The value of the query priority. |
| user_role_wild_card | Boolean | If TRUE, the WLM queue treats an
asterisk (*) as a wildcard character in user user strings in the
WLM configuration. |
Sample query
The first user-defined service class is service class 6, which is named Service class #1. The following query displays the current configuration for service classes greater than 4. For a list of service class IDs, see WLM service class IDs.
select rtrim(name) as name, num_query_tasks as slots, query_working_mem as mem, max_execution_time as max_time, user_group_wild_card as user_wildcard, query_group_wild_card as query_wildcard from stv_wlm_service_class_config where service_class > 4; name | slots | mem | max_time | user_wildcard | query_wildcard -----------------------------+-------+-----+----------+---------------+--------------- Service class for super user | 1 | 535 | 0 | false | false Queue 1 | 5 | 125 | 0 | false | false Queue 2 | 5 | 125 | 0 | false | false Queue 3 | 5 | 125 | 0 | false | false Queue 4 | 5 | 627 | 0 | false | false Queue 5 | 5 | 125 | 0 | true | true Default queue | 5 | 125 | 0 | false | false
The following query shows the status of a dynamic WLM transition. While the
transition is in process, num_query_tasks and
target_query_working_mem are updated until they equal the target
values. For more information, see WLM dynamic and static configuration
properties.
select rtrim(name) as name, num_query_tasks as slots, target_num_query_tasks as target_slots, query_working_mem as memory, target_query_working_mem as target_memory from stv_wlm_service_class_config where num_query_tasks > target_num_query_tasks or query_working_mem > target_query_working_mem and service_class > 5; name | slots | target_slots | memory | target_mem ------------------+-------+--------------+--------+------------ Queue 3 | 5 | 15 | 125 | 375 Queue 5 | 10 | 5 | 250 | 125 (2 rows)
