QLOC: Quorums With Local Reconstruction Codes

In this paper we study the problem of consistency in distributed storage systems relying on erasure coding for efficient fault-tolerance. We propose QLOC - a flexible framework supporting warm data, i.e., data which, while not being very frequently use, nevertheless continues to be accessed reads or writes regularly. builds upon (1) generic family local reconstruction codes with guarantees terms fault-tolerance, recovery from failures and degraded mode operations, can instantiated parameters customized requirements such as overhead reliability dictated by user needs operational environments, (2) quorum-based mechanisms support read-modify-write operations without any underlying atomic primitives, providing deployment choices trading-off concurrency requirements. carry out theoretical analysis code properties, experimentally benchmark performance enforcement mechanisms, demonstrating practicality proposed approach.