Hi Benjamin -
There are several variables that can impact delivery of subscriptions,, and in particular server performance. You didn't supply any information about your server environment, so I'll share some general recommendations. These aren't in any particular order:
- Subscriptions are a scheduled tasks; the tasks are handled by the Backgrounder. The Backgrounder also handles extract refreshes, so the number of Backgrounders you have configured, and their distribution (is it a single node or cluster?) will play a role in overall throughput.
- Do you have different schedules to handle the various dashboards?
- Consider the priorities in the schedule. Is everything running at the default value (50), or have you taken the time to modify schedule priority according to requirements?
- Normally, Tableau server will push subscriptions to the top of the queue, because they typically run faster than an extract refresh. Are you seeing contention? Is the Backgrounder timing out? You can check the server admin views for specifics: Background Tasks for Non Extracts
- In terms of scheduling times, that is really your call. If the data that supports a dashboard is only updated once a day, it doesn't sound practical to have a subscription run every 15 min. Similarly, if the data has NOT changed, there's no point in sending the subscription. Use the server option to "not run the subscription" if there isn't any change to the data.
- If possible, consider running subscriptions off hours. That way, your users will find the mail in the morning when they open their mailbox.