How to Improve User Search Performance — If your Confluence instance contains thousands of user accounts and you are experiencing performance issues when searching for users, the following migration guide is for you.
Migrating users from Confluence to JIRA — There is currently no way to delegate user management from JIRA to Confluence. So, if you are in a situation where your users are defined in Confluence and would like to take advantage of Confluence's ability to use JIRA user management, you will need to transfer all of your existing Confluence users into JIRA. You can do this manually, or if you have a large number of users, you can use the attached XML-RPC script.