The Problem

There is no limit on the number of subtasks that can be created against a single Jira issue. When a large number of subtasks are created on an issue (e.g. in the hundreds), Jira can experience problems with loading the issue screen for that issue. The page will often take several seconds to load, or simply crash.

Proposed Solution

A new advanced setting to be made available to Jira System Administrators, to set the maximum number of subtasks to be created on a single issue. This could be switched off by default.

On an issue where the subtask limit has been reached, a user attempting to submit the "create sub-task" form would be presented with an error such as "The maximum number of subtasks allowed on this issue has been reached."