User guide

user groups or query groups for the default queue.The default queue must always be the last queue in
the WLM configuration.
As with other parameters, you cannot modify the WLM configuration in the default parameter group.
Clusters associated with the default parameter group always use the default WLM configuration. If you
want to modify the WLM configuration, you must create a parameter group and then associate that
parameter group with any clusters that require your custom WLM configuration.
Configuring the wlm_json_configuration Parameter
To configure WLM, you modify the wlm_json_configuration parameter and format it in JavaScript
Object Notation (JSON). If you configure WLM by using the Amazon Redshift console, you do not need
to understand JSON formatting because the console provides an easy way to add queues and configure
their properties. For more information about configuring WLM by using the Amazon Redshift console,
see Modifying a Parameter Group (p. 74). The following screenshot shows the WLM configuration in the
Amazon Redshift console.
If you configure WLM by using the AWS CLI, Amazon Redshift API, or one of the AWS SDKs, use the
rest of this section to learn how to construct the JSON structure for the wlm_json_configuration
parameter. The following example is the default WLM configuration, which defines one queue with a
concurrency level of five:
{
"query_concurrency":5
}
The default WLM configuration is very simple, with only queue and one property.You can add more
queues and configure multiple properties for each in the JSON structure.The following syntax represents
the JSON structure that you use to configure multiple queues with multiple properties:
[
{
"ParameterName":"wlm_json_configuration", "ParameterValue":
"[
{
"q1_first_property_name":"q1_first_property_value",
"q1_second_property_name":"q1_second_property_value",
...
},
{
"q2_first_property_name":"q2_first_property_value",
API Version 2012-12-01
69
Amazon Redshift Management Guide
Configuring the wlm_json_configuration Parameter