Try using the Performance Recording feature - this can be a great help in tracking down what's taking so long. From the Help menu select Settings and Performance --> Start Performance Recording. Then do some filtering, etc to record typical activity. Then go back to the Help menu and select Stop Performance Recording. A new workbook will be automatically generated showing all sorts of information about the queries being executed and where the time is being eaten up.
Create a performance recording in Tableau Desktop
To start recording performance, follow this step:
Help > Settings and Performance > Start Performance Recording
To stop recording, and then view a temporary workbook containing results from the recording session, follow this step:
Help > Settings and Performance > Stop Performance Recording
You can now view the performance workbook and begin your analysis.
If you are sending the recording to Tableau Support, save this workbook as a packaged workbook (.twbx) file, and then send it.
Interpret a performance recording workbook
A performance recording workbook is a Tableau dashboard that contains three views: Timeline, Events, and Query.
The uppermost view in a performance recording dashboard shows the events that occurred during recording, arranged chronologically from left to right. The bottom axis shows elapsed time since Tableau started, in seconds.
In the Timeline view, the Workbook, Dashboard, and Worksheet columns identify the context for events. The Event column identifies the nature of the event, and the final column shows each event’s duration and how it compares chronologically to other recorded events:
The middle view in a performance recording workbook shows the events, sorted by duration (greatest to least). Events with longer durations can help you identify where to look first if you want to speed up your workbook.
Different colors indicate different types of events. The range of events that can be recorded is:
- Computing layoutsIf layouts are taking too long, consider simplifying your workbook.
- Connecting to data sourceSlow connections could be due to network issues or issues with the database server.
- Executing query
- For live connections, if queries are taking too long, it could be because the underlying data structure isn’t optimized for Tableau. Consult your database server’s documentation. As an alternative, consider using an extract to speed performance.
- For extracts, if queries are taking too long, review your use of filters. If you have a lot of filters, would a context filter make more sense? If you have a dashboard that uses filters, consider using action filters, which can help with performance.
- Generating extractTo speed up extract generation, consider only importing some data from the original data source. For example, you can filter on specific data fields, or create a sample based on a specified number of rows or percentage of the data.
- GeocodingTo speed up geocoding performance, try using less data or filtering out data.
- Blending dataTo speed up data blending, try using less data or filtering out data.
- Server renderingYou can speed up server rendering by running additional VizQL Server processes on additional machines.
If you click on an Executing Query event in either the Timeline or Events section of a performance recording dashboard , the text for that query is displayed in the Query section.
If you are connected to a published data source, the query text is displayed in XML. If you are connected to the data source directly, the query is displayed in SQL like shown below:
If it makes sense, you can use the query text to work with your database team on optimizing at the database level. Sometimes the query is truncated and you’ll need to look in the Tableau log to find the full query. Most database servers can give you advice about how to optimize a query by adding indexes or other techniques. See your database server documentation for details.
Sometimes for efficiency, Tableau combines multiple queries into a single query against the data. In this case, you may see an Executing Query event for the Null worksheet and zero queries being executed for your named worksheets.
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