v-Bundle: Flexible Group Resource Offerings in Clouds

Traditional Infrastructure-as-a-Service offerings provide customers with large numbers of fixed-size virtual machine (VM) instances with resource allocations that are designed to meet application demands. With application demands varying over time, cloud providers gain efficiencies through resource consolidation and over-commitment. For cloud customers, however, this leads to inefficient use of the cloud resources they have purchased. To address cloud customers' dynamic application requirements, we present a new cloud resource offering, called v-Bundle, which makes flexible the exchange of resource capacity among multiple VM instances belonging to the same customer. Specifically targeting network resources, for each customer application, we first use DHT-based techniques to achieve an initial VM placement that minimizes its use of the data center network's bi-section bandwidth. When VMs' networking requirements change, the customer can then use v-Bundle to trade the networking resources allocated to her application. v-Bundle maintains information about network resources with any-cast tree-based methods implemented as extensions of the Pastry pub-sub core. Experimental evaluations show that the approach can scale well to thousands of hosts and VMs, and that v-Bundle can provide customers with better bandwidth utilization and improved application quality of service through borrowing extra bandwidth when needed, at no additional cost in terms of the total resources allocated to the customer.