Filter and aggregate your data
If your dataset still does not offer a satisfying user experience with the SuperTables extension then you might consider aggregating your dataset to a different level. Another option is to apply filters (on for instance Data periods, departments, regions or categories of your choice ) before feeding it to the SuperTables extension through the Extensions API. This is all to reduce the number of rows that will be transferred to your extension.
Use Extracts instead of live connections
In general it is best practice in Tableau to use a data source based on an extract (refreshing overnight would offer ‘almost live’ datasets for your SuperTables dashboards). This way your performance gets optimized in the datasource and calculated fields are pre-calculated as well.
No overhead on data sheets
Due to the data transfer mechanism of the Tableau Extensions API it is important to remove as much overhead columns (meta information) from the worksheet in your Tableau Workbook. Remove all columns (dimensions or measures) that will not be used in the extension. Besides the number of rows, also the number of columns affect the user experience of your Tableau users.
Local rendering of extensions