Design and Implementation of the iWarp Protocol in Software

D. Dalessandro, A. Devulapalli, and P. Wyckoff (USA)

Keywords

RDMA, iWARP, TCP, RDDP

Abstract

The term iWarp indicates a set of published protocol specifications that provide remote read and write access to user applications, without operating system intervention or intermediate data copies. The iWarp protocol provides for higher bandwidth and lower latency transfers over existing, widely deployed TCP/IP networks. While hardware imple mentations of iWarp are starting to emerge, there is a need for software implementations to enable offload on servers as a transition mechanism, for protocol testing, and for fu ture protocol research. The work presented here allows a server with an iWarp network card to utilize it fully by implementing the iWarp protocol in software on the non-accelerated clients. While throughput does not improve, the true benefit of reduced load on the server machine is realized. Experiments show that sender system load is reduced from 35% to 5% and receiver load is reduced from 90% to under 5%. These gains allow a server to scale to handle many more simultaneous client connections.

Important Links:



Go Back