Hacker News new | comments | show | ask | jobs | submit login

Is it just me, or don't the graphs at the bottom left appear to indicate that Fastpass achieves "improved fairness" through considerably diminished performance, especially under low contention?



It took me a while, but I believe this might be one of the few times that a stacked line chart would better serve the purpose. Total throughput is the addition of the 5 "per-connection throughputs." Thus, during the peak, we see ~2 Gb/s for all 5 servers, totaling ~10 Gbps. In the top graph, we see 1-3 Gbps for the 5 servers, totally ~10 Gbps. It would be more clear if a "total throughput" line were added or the author used a stacked line chart, since we're looking at both total throughput and fairness.


Right, but I mean the start and end of those graphs. That shows 6+ Gbit for one flow without Fastpass, and around 4 Gbit with it.


Yeah, that's fairly poor. It should be 10 Gbps for the first 30 seconds.


It's not just you. If you read it carefully you'll notice that the evaluation only shows that the improvements are that TCP retransmits are reduced from 4 to 2 per second, which probably has no impact. And that the latency is only better in a contrived example with iperf and ping. The paper really demonstrates no tangible benefit.




Guidelines | FAQ | Support | API | Security | Lists | Bookmarklet | Legal | Apply to YC | Contact

Search: