| This dissertation investigates the use of a hardware mechanism called Eager Data Transfer (EDT) for achieving the reduction of communication latency for user-level network protocol. To reach the goal, the dissertation addresses the following research issues.; First, the development of a communication system performance evaluation tool called Linux/SimOS is presented. Linux/SimOS provides a full system profiling capability to allow measurement at various level including hardware, operating system, and application.; Second, the performance analysis of network protocols is presented. For the assessment of overhead related to network protocol operation, Linux/SimOS was used to perform the detailed latency measurements for TCP/IP, UDP/IP, and M-VIA network protocols.; Finally, EDT is proposed for reducing communication latency. Since the data transfer time constitutes a significant portion of overall communication latency, the reduction of data transfer time leads to low communication latency. EDT is based on cache coherence interface hardware for reducing data transfer overhead during network protocol operation. Our simulation result shows that EDT is very effective in attaining low communication latency compared to the DMA-based approaches. |
