Exploiting Bandwidth to Reduce Average Memory Access Time in Scalable Multiprocessors.
ROCHESTER UNIV NY DEPT OF COMPUTER SCIENCE
Pagination or Media Count:
The overhead of remote memory accesses is a major impediment to achieving good application performance on scalable shared-memory multiprocessors. This dissertation explores ways in which to exploit network and memory bandwidth in order to reduce the average cost of memory accesses. We consider scenarios 1 where the remote access cost is dominated by contention, and 2 where the hardware provides abundant band- width and the remote access time is dominated by the unsaturated requestaccessreply sequence of operations. We introduce and evaluate two techniques for increasing the effective bandwidth available to processors, software interleaving and eager combining. We also evaluate strategies for hiding the high cost of remote accesses, including several forms of prefetching and update-based coherence protocols. We use both analytic models and detailed simulations of multiprocessor systems to quantify the effectiveness of these techniques, and to provide insight into the potential and limitations of exploiting bandwidth to reduce average memory access cost.
- Computer Hardware