2000 Suite consisting of Speedway, Hangar, Rust Valley, Canyon, Chamber, Stations, Islands, Race Track, and Chapel . First, effectiveness of the prefetch instruction in Intel s media extension to prefetch data in a timely fashion was evaluated on several kernels. It can be seen that as an application becomes more memory-bound, prefetching can help performance greatly. Matrix multiplication has been a rather tricky kernel to optimize for cache prefetch. We tried a number of different prefetch strategies varying the location at which prefetches are inserted, in a manner to spread out the prefetches and overlap the prefetch latency with computations.
Performance is sensitive to where and how the prefetches are inserted.
It is seen that though both prefetch methods are better than the code without any prefetches. However, prefetches need to be inserted very carefully. Furthermore, prefetch strategies may show varying performance depending on the size of the data set. The studies with kernels are not sufficient to reveal the effectiveness of prefetching, because kernels can be manually optimized. Hence evaluation on real world applications was undertaken.