Suppose you want to improve the system throughput by limiting the number of queries that can run concurrently on a system to never exceed three queries. To do this, place any queries that exceed this limit in a delay queue. When one query completes, the next query in the queue starts executing.
- Select a ruleset to edit.
- Open the Workload Designer portlet and the Workload Designer view.
- From the For System list, select PROD1.
- In the local Working section, click the ruleset name, FILTERS/THROTTLES.
- Create a new system throttle.
- From the ruleset toolbar, click Throttles.
- Next to System Throttles, click .
- Enter the name of the throttle, in this case Concurrent Queries.
- Select the Rule Type option Collective.
- Click Save.
- Add classification criteria for the system throttle to apply to all users.
- Click the Classification tab.
- From the Add Classification Criteria list, select Request Source.
- Click Add.The Edit Request Source Criteria dialog box appears.
- From the Source Type list, select Username.
- From the Usernames list, select All.
- Click Include.
- Click OK.
- Click Save.
- Add throttle limits to allow only three queries to execute at a time.
- Click the State Specific Settings tab.
- Under Default Settings, type 3 in the box to set the concurrency limit.
- Select Delay to place queries exceeding the limit in a delay queue.
- Click Save.
- Activate the ruleset.
- Go back to the Workload Designer view.
- For the FILTERS/THROTTLES ruleset, click and select Make Active.
- [Optional] Review the queries in the delay queue.
- Open the Workload Monitor portlet.
- Click in the portlet frame and select Settings.
- Click the Systems tab.
- From the Systems list, select PROD1.
- Click OK.
- From the toolbar, click on Delayed Requests to view metrics for requests that were delayed by throttles.
- Click on the Session ID to view more details.