[JIRAALIGN-1375] Team Room takes 20 seconds or more to load

Issue Summary

For customers with large amounts of data stored in Jira Align, the Team Room can take a long time to load. In some cases it can take up to 20 seconds or more to render the page.

This can be demonstrated on ac10xm1.agilecraft.com. Customers are seeing long wait times when trying to load the team room.

The slowdown seems to be centered around the call to this URL when bringing up the team room (this was also observed on customer sites):

https://ac10xm1.agilecraft.com/TeamRoom/Ajax/Dashboard?viewType=TeamView&UID=1&IterationID=98&TeamID=20

Steps to Reproduce

1. Log in to ac10xm1.agilecraft.com
2. In tier 1 Enter "AgileCraft Core" as the Program
3. Navigate to Team Room
4. Select "Craftsmen" for the team
5. Select Q4 CRM GNR 4.5 for the iteration
6. Make sure "Dashboard" view and "Team View" are selected
7. Wait for the team room to load

Expected Results

Team room loads in less than 10 seconds (or faster)

Actual Results

Team room can take up 20 seconds or longer to load.

Workaround

Currently there is no known workaround for this behavior. A workaround will be added here when available

Additional Notes
The performance gets worse as more stories and tasks are added to the Team and Iteration.
In our example, we had 976 Stories and 887 tasks associated with the team and Sprint:

A HAR capture from ac10xm1 is attached to this Jira ticket, and the analysis shows that we spend the bulk of the page load time in the URL mentioned above: