Leapfront Distance

The leapfront distance determines when a client is allowed to play the role of a frontrunner depending on how far ahead from the file cursor the client cursor has moved. For convenience, we introduce the leapfront factor as the ratio of the leapfront distance over the active length. In Figure 17, we notice that as the leapfront factor grows larger than 1, the network throughput drops and the miss ratio increases. Setting the leapfront distance equal to the active length gives good performance by allowing the active region to move smoothly forward; larger leapfront distances tend to reduce spatial locality among different clients and lead to lower throughput. The active length was set equal to 16MB throughout our study.