FARAD: A Storage System for Random Real-Time Data

Many multimedia applications demand real-time and high throughput data retrieval from a storage subsystem. Very often, the access pattern of such retrieval has random nature. This is due to realtime playback of video clips that are physically separated on the disk platter (non-linear editing), or due to serving many independent clients simultaneously (video on demand). Hence, minimizing the overhead incurred by random access is very important for multimedia applications. Moreover, the storage subsystem must response in real-time to such random disk access requests for failure to do so will cause uncomfortable noise on played images and sound. — We have developed a collection of technologies for multimedia storage systems, called FARAD. This paper focuses on the most important part of the technologies: a new disk management algorithm that minimizes the random access overhead. While existing algorithms treat the rotational delay as uncontrollable, the FARAD controls both seek and rotational delay by proper scheduling and data placement so as to reduce overhead under random data access environment.

Published

1996-02

Content type

Original Research

DOI

10.5594/M00460

ISBN

978-1-61482-924-9