Dynamic Policy Disk Caching for Storage Networking

Storage networking is becoming increasingly important, especially with the emergence of SAN over IP technologies. It plays an important role in resource consolidation and management for various systems, spanning from a large-scale data center to a set of interconnected workstations. However, existing storage systems may not scale well under the load from relatively large number of clients. Local disk caching has the potential to solve this problem by leveraging data locality with clientside storage, but it is lacking for typical storage networks. Addressing to this, this paper presents a general block-level disk cache, named dm-cache, built on top of Linux’s device-mapper architecture. It can be transparently plugged into a client for any storage systems, and supports dynamic customization for policy-guided optimizations. Experimental evaluation based on file system benchmarks and a typical application has been conducted to investigate its performance over iSCSI in a typical blade center. The results show that dm-cache can significantly improve the performance and scalability of storage system by orders of magnitude.

By: Eric Van Hensbergen; Ming Zhao

Published in: RC24123 in 2006


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