Definition: Performance acceptance criteria are the agreed performance conditions a user story must meet to be considered done, usually expressed as response times. They are agreed between the performance tester and the product owner during sprint planning.
So what? Without agreed criteria, performance test results are hard to judge and easy to ignore. Clear criteria turn "it feels slow" into a pass or fail the whole team can act on.
Examples: Agreeing that a login request must respond within two seconds under expected load. Reviewing performance test results against the criteria and sharing them with the whole agile team.
