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Jumbo Frames

Another interesting result is the nearly flat connection rate for transfers less than 8 kB. Even with jumbo frames enabled one would expect a more significant decrease in the connection rate. It appears that the Alteon firmware is optimized for bulk data transfers rather than fast connection set-up. We ran some tests using a single client thread requesting 1 kB transfers on Alteon, Intel gigabit, and Intel 100 Mb adapters. This configuration measures connection latency. We found the Alteon adapter to be between two and three times slower than the Intel gigabit and 100 Mb adapters, respectively. The high connection set-up cost on the Alteon adapter most probably accounts for the flat connection rate.



Philippe Joubert 2001-05-01