Pricing Intra-Datacenter Networks with Over-Committed Bandwidth Guarantee

Current IaaS clouds provide performance guarantee on CPU and memory but no quantitative network performance for VM instances. Our measurements from three production IaaS clouds show that for the VMs with same CPU and memory, or similar pricing, the difference in bandwidth performance can be as much as 16×, which reveals a severe price-performance anomaly due to a lack of pricing for bandwidth guarantee. Considering the low network utilization in cloud-scale datacenters, we address this by presenting SoftBW, a system that enables pricing bandwidth with over commitment on bandwidth guarantee. SoftBW leverages usage-based charging to guarantee price-performance consistency among tenants, and implements a fulfillment based scheduling to provide bandwidth/fairness guarantee under bandwidth over commitment. Both testbed experiments and large-scale simulation results validate SoftBW’s ability of providing efficient bandwidth guarantee, and show that by using bandwidth over commitment, SoftBW increases 3.9× network utilization while incurring less than 5% guarantee failure.