Tombolo: Performance enhancements for cloud storage gateways

Object-based cloud storage has been widely adopted for their agility in deploying storage with a very low up-front cost. However, enterprises currently use them to store secondary data and not for expensive primary data. The driving reason is performance; most enterprises conclude that storing primary data in the cloud will not deliver the performance needed to serve typical workloads. Our analysis of real-world traces shows that certain primary data sets can reside in the cloud with its working set cached locally, using a cloud gateway that acts as a caching bridge between local data centers and the cloud. We use a realistic cloud gateway simulator to study the performance and cost of moving such workloads to different cloud backends (like Amazon S3). We find that when equipped with the right techniques, cloud gateways can provide competitive performance and price compared to on-premise storage. We also provide insights on how to build such cloud gateways, especially with respect to caching and prefetching techniques.