Thursday, August 15, 2013

SIGCOMM13: ElasticSwitch: Practical Work-Conserving Bandwidth Guarantees for Cloud Computing


The paper was presented by Lucian Popa.
Other co-authors are: Praveen Yalagandula, Sujata Banerjee, Jeffrey C. Mogul, Yoshio Turner and Jose Renato Santos.

This talk was about network resource guarantees in cloud computing. The author presented ElasticSwitch, an ef´Čücient and practical approach for providing bandwidth guarantees.

Goal of ElasticSwitch:
  • provide minimum bandwidth guarantees in Clouds
  • work-conserving allocation
  • be practical

ElasticSwitch design:
ElasticSwitch resides in the hypervisor of each host, not in the individual VMs. ElasticSwitch contains two components: guarantee partitioning and rate allocation. To guarantee partition, ElasticSwitch turns hose model into a VM-to-VM pipe guarantee. Guarantee partitioning leverages max min allocation and there are 3 goals: safety, efficiency and no starvation.
In rate allocation, ElasticSwitch uses rate limiters and increases rate between X-Y above it’s partition when there is no congestion between X and Y. Congestion is detected through dropped packets, or use ECN. The adaptive algorithm used in ElasticSwitch is from Seawall (NSDI 11).


Evaluation:
The testbed contains 100 servers and 1Gbps tree network. The first workload tested is many-to-one workload. The result shows that ElasticSwitch can provide bandwidth guarantees and achieve ideal situation. The second workload is MapReduce. It shows that in the worst case, job completion time is much shorter when using ElasticSwitch comparing with no bandwidth guarantees.

More details can be found: http://conferences.sigcomm.org/sigcomm/2013/papers/sigcomm/p351.pdf