Adding the Agile Wallboard or Sprint-related gadgets to a Confluence page results in a dramatic increase in the number of requests and cause slowness.

Steps to Reproduce:

1. Install Jira and Confluence , in this test Jira Software 7.3.7 and Confluence 6.8.0 are used
2. Create Application Link between Jira and Confluence
3. In Jira,
   1. go to Dashboard >> add new gadget >> search for Agile Wallboard >> Show XML Link > Copy the gadget's URL:
      
   2. create Scrum software development projects
   3. create boards for the projects
   4. create sprints in the boards
   5. create issues in the project
   6. add issues into the sprints, then start the sprint
4. in Confluence
   1. go to Administrations >> External Gadgets >> paste the URL from step 2 into the Gadget Specification URL, or add the full gadget feed
   2. create pages and insert Jira Agile Wallboard gadget(s) into it

This problem is also reproducible with Sprint-related gadgets, tested with:

1. Sprint health
2. Spring burndown
3. Days remaining in sprint

Expected results

Page load time is not affected significantly.

Actual results

Page with 1 Agile Wallboard gadget will add extra time to load. Following are the test results for various of pages:

Attached are the Chrome's tools as shown:

Inspecting the network tab, we can see that adding one of those gadgets to a page increases the number of requests to 500+ for a single page load. Each gadget added to the page will add more 500+ requests as well, even if it is using the same settings as the existing ones. Most of those requests are related to CSS and JS files associated with the gadgets.

This results in several stalled requests since the browsers have a limitation on the number of parallel requests. Each stalled one can take a few seconds, leading to a long page load time due to the accumulated stalls.

This behavior is not reproducible when adding the same gadgets to a Jira dashboard, so it is isolated to using them on Confluence pages.

Workaround

Enabling caching of static files on the proxy or load balancer helps. Since most of the extra requests are for static files, it decreases the stalled time for each one of them, reducing the overall page load time. Consult your network team to check if this is a viable option.

It is also good to avoid adding multiple of the affected gadgets to a single page, since each one of them will increase the page load time even further.