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The Competitors

We implemented prefetching algorithms that represent the FS, FA, and AS classes.

Within the FS and FA classes we pick members with small, medium and large $ p$. In Figure 6, we observe that for the FA algorithms there is no optimal fixed value for $ g$ that works for all workloads. We have chosen $ g$ to be half of $ p$ as that works best for the widest variety of workloads. For AS algorithms, we chose two popular variants, which adapt $ p$ linearly (AS $ _\textrm{Linear}$ ) and exponentially (AS $ _\textrm{Exp}$ ). We also compare with OBL and the case with no prefetching.

Figure 6: On x-axis we vary the trigger distance ($ g$) in an FA algorithm with $ p=256$. On the y-axis we show the throughput when using a $ 120$ MB cache. When using five fast streams we get higher throughput with higher values of $ g$, whereas, with a hundred slower streams, a smaller $ g$ performs better.
\begin{figure}\begin{center}
{\small Effect of trigger distance ($g$) in {\em FA...
...rithms.}
\epsfig{figure=numbers/g_var.eps, width=3.0in}
\end{center}\end{figure}



root 2006-12-19