Designing Efficient Cooperative Caching Schemes for Multi-Tier Data-Centers over RDMA-enabled Networks

Abstract

Caching has been a very important technique in improving the performance and scalability of web-serving datacenters. The research community has proposed cooperation of caching servers to achieve higher performance benefits. These existing cooperative caching mechanisms often partially duplicate the cached data redundantly on multiple servers for higher performance (by optimizing the datafetch costs for multiple similar requests). With the advent of RDMA enabled interconnects these basic data-fetch cost estimates have changed significantly. Further, the effective utilization of the vast resources available across multiple tiers in today’s data-centers is of obvious interest. Hence, a systematic study of these various issues involved is of paramount importance. In this paper, we present several cooperative caching schemes that are designed to benefit in the light of the above mentioned trends. In particular, we design schemes that take advantage of the RDMA capabilities of networks and the multitude of resources available in modern multi-tier data-centers. Our designs are implemented on InfiniBand based clusters to work in conjunction with Apache based servers. Our experimental results show that our schemes achieve a throughput improvement of up to 35% as compared to the basic cooperative caching schemes and 180% better than the simple single node caching schemes. Our experimental results lead us to a new scheme which can deliver good performance in many Caching has been a very important technique in improving the performance and scalability of web-serving datacenters. The research community has proposed cooperation of caching servers to achieve higher performance benefits. These existing cooperative caching mechanisms often partially duplicate the cached data redundantly on multiple servers for higher performance (by optimizing the datafetch costs for multiple similar requests). With the advent of RDMA enabled interconnects these basic data-fetch cost estimates have changed significantly. Further, the effective utilization of the vast resources available across multiple tiers in today’s data-centers is of obvious interest. Hence, a systematic study of these various issues involved is of paramount importance. In this paper, we present several cooperative caching schemes that are designed to benefit in the light of the above mentioned trends. In particular, we design schemes that take advantage of the RDMA capabilities of networks and the multitude of resources available in modern multi-tier data-centers. Our designs are implemented on InfiniBand based clusters to work in conjunction with Apache based servers. Our experimental results show that our schemes achieve a throughput improvement of up to 35% as compared to the basic cooperative caching schemes and 180% better than the simple single node caching schemes. Our experimental results lead us to a new scheme which can deliver good performance in many scenarios.