Scheduling Feed Retrieval

The popularity of RSS and similar feed formats is growing fast. This paper gives an overview of the standards and implementations in this field, and analyzes whether they allow scheduling the retrieval of feed updates. As will be shown, such support is very limited and current feed readers therefore poll providers at fixed rates. The measurements performed as part of our study show that in general a clear mismatch exists between such fixed polling rate of feed readers and the rate at which providers update their feeds; a significant performance gain is therefore possible by embedding scheduling information within feeds. This paper proposes a scheduling approach that both reduces lag in updates for active feeds and reduces wasted resources for less active feeds. Simulations show that our approach reduces the perceived lag by twenty percent, while having the same resource requirements as a fixed-rate algorithm.