If a job has a very large workspace, and a very permissive artifact expression (like */.jar), a user can single handledly bring down a Jenkins instance by tabbing in and out of the artifact field. Each time the user tabs out of the field, Jenkins does an ajax post, resultining in a recursive search of the filesystem.

Jenkins should be smart enough to cancel previous ajax requests for validating the artifact glob expression, or use some other approach to prevent the entire system from going down.