SpongeNet: Towards bandwidth guarantees of cloud datacenter with two-phase VM placement

In today's production-grade cloud datacenter, cloud service providers do not offer any bandwidth guarantees between VMs, which results in unpredictable performance of tenants' applications. To address this issue, we present SpongeNet, a solution that provides bandwidth guarantees for tenants with a novel network abstraction model and a two-phase VM placement algorithm. Prior solutions have significant limitations: 1) the existing coarse-grained network abstraction models cannot fully express tenants' network requirements and waste a lot of bandwidth resources in demand level; 2) the prior VM placement algorithms, take neither the two scheduling phases nor the tenants' requirements into consideration. As an extension of the existing studies, the proposed network abstraction model in this paper, called Fine-grained Virtual Cluster or FGVC, provides a more precise and flexible way for tenants to specify network requirements and realizes bandwidth saving. SpongeNet also proposes a novel two-phase VM placement algorithm that provides the optimal combinations of ordering policies and dispatching policies in consideration of different goals. Extensive simulations based on real application traces and 3-level tree topology show that SpongeNet provides 48% bandwidth saving than the state-of-art solutions (e.g., the Oktopus system), while significantly improving the throughput rates by 18% and response times by 92%.