Flyways To De-Congest Data Center Networks. 论文

摘要

Abstract – Astudyofapplicationdemandsfromaproductiondatacenterof1500serversshowsthatexceptforafewoutliers, application demandscan begenerally metbyanetwork that isslightly oversubscribed. Eliminating over-subscription is hence a needless overkill. In a significant departure from recent proposals that do so, we advocate a hybrid architecture. The base network is provisioned for the average case, is oversubscribed, and canbebuiltwith any ofthe existing networkdesigns. Totacklethehotspotsthatremain,weaddextra links on an on-demand basis. Theselinks called flywaysprovideadditional capacity whereandwhenneeded. Ourresults showthatevenafewadditional flywayssubstantially improve performance (by over 50%), as long as they are added at the right place in the network. We consider two design alternatives foradding flywaysatnegligibleadditional cost: onethat useswirelesslinks (60GHzor802.11n) andanother thatuses commodityswitchestoaddcapacityinarandomizedmanner. 1.