Monday, February 25, 2013

Shark: Scaling File Servers via Cooperative Caching

by S. Annapureddy et al., NSDI 2005.
Abstract:
Network file systems offer a powerful, transparent inter- face for accessing remote data. Unfortunately, in current network file systems like NFS, clients fetch data from a central file server, inherently limiting the system’s ability to scale to many clients. While recent distributed (peer-to- peer) systems have managed to eliminate this scalability bottleneck, they are often exceedingly complex and pro- vide non-standard models for administration and account- ability. We present Shark, a novel system that retains the best of both worlds—the scalability of distributed systems with the simplicity of central servers. 
Shark is a distributed file system designed for large- scale, wide-area deployment, while also providing a drop- in replacement for local-area file systems. Shark intro- duces a novel cooperative-caching mechanism, in which mutually-distrustful clients can exploit each others’ file caches to reduce load on an origin file server. Using a dis- tributed index, Shark clients find nearby copies of data, even when files originate from different servers. Perfor- mance results show that Shark can greatly reduce server load and improve client latency for read-heavy workloads both in the wide and local areas, while still remaining competitive for single clients in the local area. Thus, Shark enables modestly-provisioned file servers to scale to hundreds of read-mostly clients while retaining tradi- tional usability, consistency, security, and accountability. 

Link to the full paper:
http://www.cse.buffalo.edu/faculty/tkosar/cse710_spring13/papers/shark.pdf

OceanStore: An Architecture for Global-Scale Persistent Storage

by J. Kubiatowicz et al., ASPLOS 2000.

Abstract:
OceanStore is a utility infrastructure designed to span the globe and provide continuous access to persistent information. Since this infrastructure is comprised of untrusted servers, data is pro- tected through redundancy and cryptographic techniques. To im- prove performance, data is allowed to be cached anywhere, any- time. Additionally, monitoring of usage patterns allows adapta- tion to regional outages and denial of service attacks; monitoring also enhances performance through pro-active movement of data. A prototype implementation is currently under development. 

Link to the full paper:
http://www.cse.buffalo.edu/faculty/tkosar/cse710_spring13/papers/oceanstore.pdf