Smart DRILL Load Balancing Protocol: Wise Exploration and Reacting

Abstract

Load balancing at data centers is an active research area. The literature contains various load balancing protocols. DRILL is one recognized load balancing algorithm. DRILL is inspired by concept of “the power of two choices” through enabling forwarding packets based on two factors: past experience through selecting least loaded ports and exploring new choices through random selection of new ports. This article proposes a newer variant of DRILL named smart DRILL or SDRILL. It balances between relying on the last ports or exploring new ports through using the buffer status as indicator to the need of exploring more new ports. Also, SDRILL reacts faster when the congestion is increasing and slower when the congestion is not increasing highly. Experimental results show that SDRILL was superior in terms of flow completion time for the most used flows in datacenters: data mining and web-search while it was in the average for general flows. Also, SDRILL was superior in terms of both tail latency and throughput.