Bandwidth guarantee in a distributed multimedia file system using network attached autonomous disks

File systems for multimedia applications must support high bandwidth streaming with strict rate guarantees. Recently we proposed a distributed file system built using autonomous disks (S. Mukherjee et al., 1999). Autonomous disks are attached directly to the network and are able to perform lightweight processing. The paper describes the methodologies used to make the file system quality of service (QoS) aware and real-time sensitive. We propose efficient bandwidth allocation and enforcement policies that can keep the servers stateless. The policies are implemented in Linux kernel along with the file system. Using experimental results we show the effectiveness of the policies, and the enforcement of bandwidth allocation and usage in a fair manner. We also show that the overhead of the proposed mechanism on the overall system performance is very minimal.