Abstract— Peer-to-peer (P2P) video systems provide a costeffective way for a large number of hosts to colloaborate for video sharing. Two features characterize such a system: 1) a video is usually available on many participating hosts, and 2) different hosts typically have different sets videos, though some may partially overlap. From a client’s perspective, it can be served by any host having the video it requests. From a server’s perspective, it be used to serve any client requesting the videos it has. Thus, an important question is, which servers should be used to serve which clients in the system? In this paper, we refer to this problem as service scheduling and show that different matches between clients and servers can result in significantly different system performance. Finding a right server for each client is challenging not only because a client can choose only the servers that are within its limited search scope, but also because clients arrive at different times, wh...