Krishnaswamy, L. (CSE) – Network Load Balancing for Geographically Distributed Datacenters

As datacenters scale up and become more geographically distributed, wide-area network inter-datacenter traffic, which typically consists of data-heavy tasks, has become increasingly prevalent. Some of the noteworthy challenges raised by the coexistence and interaction between inter- and intra-datacenter traffic are the differences in their QoS requirements, link utilization, and round-trip times. To the best of our knowledge, these challenges have not yet been addressed by current datacenter load balancers. To highlight this gap, we conducted a comparative performance study of state-of-the-art datacenter load balancers. Through extensive simulations, we study how they perform under different network topologies and workloads, including intra-datacenter, inter-datacenter, and mixed intra- and inter-datacenter workloads that reflect how datacenters have evolved to keep up with their continuously changing driving application landscape. Our study shows that current load balancers are not able to adequately distribute load under inter-DC workloads as well as mixed intra- and inter-datacenter traffic coexistence.
Motivated by our observations, we introduce Balancia, a transport agnostic, lightweight network load balancer that dynamically switches between per-flow and per-packet control in order to provide adequate performance for both intra- and inter-DC traffic given their different characteristics and quality-of-service (QoS) requirements. We show that, when compared against state-of-the-art load balancers, Balancia achieves close to 80% reduction in the 99% tail flow completion times for inter-datacenter traffic in the presence of intra- and inter-datacenter workload coexistence. Further in this work, we explore proactively monitoring for congestion with the help of phantom queues and rerouting flows in a timely manner. Through Balancia2.0 we decouple congestion control and load balancing signaling, and examine its effects on DC and WAN traffic.

Event Host: Lakshmi Krishnaswamy, Ph.D. Candidate, Computer Science & Engineering

Advisor: Katia Obraczka

Zoom: https://ucsc.zoom.us/j/94414934371?pwd=7P3Umt0QQ930ESV02jMvCVHVbkIp9r.1

Passcode: 905786