Packet scheduler for meeting deadline in 4-4; 1-4 architecture

摘要

The distributed computing models such as MapReduce, Dryad, cluster based file systems, query to web search engine, parallel scientific applications and many other are associated with problems such as incast congestion, queue buildup and memory pressure. These adversities hinders the flows to meet their associated deadlines and ultimately the service level agreement (SLA). There are two classes of solutions proposed for the problems of congestion and meeting deadlines for the flows - a congestion control at the transport layer and resource allocation at the network layer. The proposed solutions at the transport layer modulated the TCP window size according to the extent of congestion and the deadline value associated with the flows. These solutions are proposed based on the assumption that the intermediate switches maintain soft-state about the flows. Thus, the entire flow has to follow a static path from begin to end. Contrast to this, the location based routing proposed for DCN tries to utilize the path diversity provided by the underlying architectures by distributing the flows among all the available outgoing paths using the Equal Cost Multiple Paths (ECMP). In this paper, we propose a packet scheduler that helps the flow to meet their associated deadline. We consider our proposed 4-4, 1-4 architecture as an example architecture for location based routing. Packet scheduler for 4-4, 1-4 helps the flows to meet their deadline by arranging the packets at the intermediate switches according to their associated deadlines. With prioritizing and scheduling the packets at the network layer, the flows are not constrained to assign to a static path and the intermediate switches need not to maintain any flow state information.