Blobseer: how to enable efficient versionning for large object storage under heavy access concurrency

To accommodate the needs of large-scale distributed P2P systems, scalable data management strategies are required, allowing appli-cations to efficiently cope with continuously growing, highly dis-tributed data. This paper addresses the problem of efficiently stor-ing and accessing very large binary data objects (BLOBs). It pro-poses an efficient versioning scheme allowing a large number of clients to concurrently read, write and append data to huge BLOBs that are fragmented and distributed at a very large scale. Scalability under heavy concurrency is achieved thanks to an original metadata scheme, based on a distributed segment tree built on top of a Dis-tributed Hash Table (DHT). Our approach has been implemented and experimented within our BlobSeer prototype on the Grid’5000 testbed, using up to 175 nodes. 1