Purdue Researchers' Paper Recognized by ACM
A paper on cloud network acceleration by a team of Purdue researchers, including graduate students Sahan Gamage and Ardalan Kangarlou (PhD'11, now at NetApp), and Professors Ramana Kompella and Dongyan Xu, that appeared in this year's ACM Symposium on Cloud Computing (SOCC'11, October 26-28) in Cascais, Portugal, was honored as one among three "Papers of Distinction" in the conference.
SOCC is ACM's premier conference in the area of cloud computing and reported an acceptance rate of 16.8% this year. The three Papers of Distinction were selected from a pool of 30 papers accepted to the conference (out of 178 total submissions).
The team's paper, entitled "Opportunistic Flooding to Improve TCP Transmit Performance in Virtualized Clouds," addresses an interesting observation about virtualized clouds: the consolidation of multiple virtual machines (VMs) in one physical server negatively affects the throughput of TCP connections between VMs in a datacenter. More specifically, as multiple VMs share a physical CPU, the VM scheduling latency, which can be in the order of tens of milliseconds, substantially increases the typically sub-millisecond round-trip times (RTTs) between physical machines in the datacenter. This subsequently causes significant degradation in TCP throughput.
To overcome this problem, the team proposed a sender-side approach called vFlood, which mitigates the impact of VM consolidation by offloading a portion of a sender VM's TCP stack to the driver domain in order to optimize the transmit path of the TCP connection. More specifically, the sender VM will opportunistically "flood" TCP packets to the driver domain, which will in turn transmit the packets to the receiver while performing congestion control on behalf of the sender VM. Their evaluation results show significant improvement in both TCP throughput and application-specific performance.
The vFlood approach complements the team's earlier approach of vSnoop, which optimizes the receive path of TCP connections between VMs in a datacenter. Incidentally, the vSnoop paper was also chosen as one of the five Best Student Paper finalists in the IEEE/ACM SuperComputing Conference held in 2010. The team plans to further investigate the integration of (and interplay between) vFlood and vSnoop, with the ultimate goal of developing an end-to-end framework for accelerating VM networking performance in virtualized clouds.
Congratulations to Gamage, Kangarlou, Kompella, and Xu!