Real-Time Virtual Shared Disk: Enabling multimedia on clusters

This paper presents the design of Real-Time Virtual Shared Disk (RTVSD), a technology that enables the sharing of disk devices in a cluster of workstations, and also supports real-time behavior of multimedia subsystems across such a cluster. RTVSD implements deadline scheduling at the disk servers, and also allows for outstanding requests to be filled or have their deadlines updated. RTVSD is implemented as a device driver in the operating system, performs all processing at the interrupt level, and thereby presents high performance. RTVSD offers an elegant solution to scalability of multimedia web servers, especially in private intranets.