You probably won't be able to do all those things every Sprint in the beginning. The ScrumMaster's job includes pushing the edges of the definition of "done" each Sprint, to eventually include all development needed for shippable product. Each Product Backlog Item should have a set of acceptance criteria.

So yes, I mean performance testing, scalability testing, deployment, compatibility testing.... In the meanwhile your product is also growing in size, and must be regression tested every Sprint. So the amount of testing must increase each Sprint.

Your only hope is automating this system testing, which I talk about here:

http://danube.com/blog/michaeljames/mock_objects_considered_insufficiently_harmful

http://danube.com/blog/michaeljames/junit_is_not_just_for_unit_testing_anymore

Some projects have contractual requirements for Independent Verification & Validation. Others find value in external User Acceptance Testing (UAT). These can also be worked into the definition of "done." Other times it's best to have your customers and end users in the Sprint Review Meetings.

Michael James
Software Process Mentor
http://www.danube.com