40th Annual IEEE/ACM International Symposium on Microarchitecture (MICRO 2007)
Impact of Cache Coherence Protocols on the Processing of Network Traffic
Chicago, Illinois, USA
December 01-December 05
ISBN: 0-7695-3047-8
Since the introduction of the 10GbE standard in 2002, the ability of general purpose processors to efficiently process network traffic with common protocols such as TCP/IP has been revisited and critically evaluated. However, recent commercially available processors such as Intel? CoreTM 2 Duo Processor introduce microarchitectural enhancements that could significantly influence the approach to accelerating network processing. We examine the network performance of a real platform containing Intel? CoreTM micro-architecture based processors, the role of coherency and a prototype implementation of direct cache placement (Direct Cache Access or DCA) of inbound network traffic. We observe that a substantial portion of the time relates to the inefficiency of I/O specific coherence protocols in the platform. We demonstrate that a relatively, low complexity implementation of DCA called `Prefetch Hint' provides a 15 to 43% speed-up to receive-side processing across a range of I/O sizes and present a detailed characterization of the benefits.
Citation:
Amit Kumar, Ram Huggahalli, "Impact of Cache Coherence Protocols on the Processing of Network Traffic," micro, pp.161-171, 40th Annual IEEE/ACM International Symposium on Microarchitecture (MICRO 2007), 2007