David Zats and Tathagata Das and Prashanth Mohan and Dhruba Borthakur and Randy H. Katz

EECS Department, University of California, Berkeley

Technical Report No. UCB/EECS-2012-33

March 15, 2012

http://www2.eecs.berkeley.edu/Pubs/TechRpts/2012/EECS-2012-33.pdf

Web applications have now become so sophisticated that rendering a typical page may require hundreds of intra-datacenter flows. At the same time, web sites must meet strict page creation deadlines of 200-300ms to satisfy user demands for interactivity. Long-tailed flow completion times make it challenging for web sites to meet these constraints. They are forced to choose between rendering a subset of the complex page, or delay its rendering, thus missing deadlines and sacrificing either quality or responsiveness. Either option leads to potential financial loss.

In this paper, we present a new cross-layer network stack aimed at reducing the long tail of flow completion times. The approach exploits cross-layer information to reduce packet drops, prioritize latency-sensitive flows, and evenly distribute network load, effectively reducing the long tail of flow completion times. We evaluate our approach through NS-3 based simulation and Click-based implementation demonstrating our ability to consistently reduce the tail across a wide range of workloads. We commonly achieve reductions of over 50\% in 99.9th percentile flow completion times without significantly impacting the median.

---

BibTeX citation:

@techreport{Zats:EECS-2012-33,
    Author= {Zats, David and Das, Tathagata and Mohan, Prashanth and Borthakur, Dhruba and Katz, Randy H.},
    Title= {DeTail: Reducing the Flow Completion Time Tail in Datacenter Networks},
    Year= {2012},
    Month= {Mar},
    Url= {http://www2.eecs.berkeley.edu/Pubs/TechRpts/2012/EECS-2012-33.html},
    Number= {UCB/EECS-2012-33},
    Abstract= {Web applications have now become so sophisticated that rendering a typical page may require hundreds of intra-datacenter flows. At the same time, web sites must meet strict page creation deadlines of 200-300ms to satisfy user demands for interactivity. Long-tailed flow completion times make it challenging for web sites to meet these constraints. They are forced to choose between rendering a subset of the complex page, or delay its rendering, thus missing deadlines and sacrificing either quality or responsiveness. Either option leads to potential financial loss.

In this paper, we present a new cross-layer network stack aimed at reducing the long tail of flow completion times. The approach exploits cross-layer information to reduce packet drops, prioritize latency-sensitive flows, and evenly distribute network load, effectively reducing the long tail of flow completion times. We evaluate our approach through NS-3 based simulation and Click-based implementation demonstrating our ability to consistently reduce the tail across a wide range of workloads. We commonly achieve reductions of over 50\% in  99.9th percentile flow completion times without significantly impacting the median.},
}

EndNote citation:

%0 Report
%A Zats, David 
%A Das, Tathagata 
%A Mohan, Prashanth 
%A Borthakur, Dhruba 
%A Katz, Randy H. 
%T DeTail: Reducing the Flow Completion Time Tail in Datacenter Networks
%I EECS Department, University of California, Berkeley
%D 2012
%8 March 15
%@ UCB/EECS-2012-33
%U http://www2.eecs.berkeley.edu/Pubs/TechRpts/2012/EECS-2012-33.html
%F Zats:EECS-2012-33