LookML developers may be able to improve dashboard performance by using aggregate awareness. With aggregate awareness, developers can create aggregate tables under LookML explore parameters, which can optimize queries for one or more tiles in a dashboard. The first step is to get the aggregate table LookML, which appears under the Get LookML option in the dashboard three-dot menu. For more information, see the aggregate_table parameter documentation page.
Find other information and recommendations about building performant dashboards in the Considerations when building performant Looker dashboards Help Center article.