Searching for users in the 'Invite team' dialog can lead to memory pressure and OutOfMemoryError in some situations

Summary

When searching for uses in the Invite team dialog, it is possible to cause high memory pressure inside the JVM, which can lead to outages and an OutOfMemoryError. This should only happen when there's a large number (10K+) of agents.

Environment

• Jira Service Desk 3.9.6

Steps to Reproduce

1. Create a large amount of users, for example, 10000 or more.
2. Create a Service Desk project.
3. Add all users to the project role Service Desk Team.
4. Click on Invite team and type several characters. For example, type 'user' then delete all characters, then type 'user' again. Repeat this operation a few times.

Expected Results

Jira does not allocate a large amount of memory and there are no performance issues.

Actual Results

A large amount of memory, possibly related to user caches, is loaded in the heap (see JRASERVER-67502). Every keystroke makes an HTTP request, so there will be multiple HTTP threads allocating a large amount of memory. This can turn the instance unresponsive due to repeated full GC operations and can eventually lead to an OutOfMemoryError.

Workaround

Disable the module responsible by the Invite team functionality, following these steps:

1. Go to Administration > Add-ons > Manage add-ons;
2. Select All add-ons on the right of the filter box just above the list of add-ons;
3. Type in "service desk project" in the filter;
4. Expand the view of the only plugin that should be displayed under the "Application Components" section, named JIRA Service Desk Project Plugin;
5. Click to expand its list of modules where it says "75 of 75 modules enabled";
6. Disable the following module:
   • Invite team (sd-project-sidebar-invite-team)

Adding agents is still possible by manually adding them to the Service Desk Team role under Project settings > Users and roles.