BubbleUp: Low Latency Fast-Scan for Media Servers

Abstract

Interactive multimedia applications require fast response time. Traditional disk scheduling schemes can incur high latencies, and caching data in memory to reduce latency is usually not feasible, especially if fast-scans need to be supported. In this study we propose a disk-based solution called BubbleUp. It significantly reduces the initial latency for new requests, as well as for fast-scan requests. The throughput of the scheme is comparable to that of traditional schemes, and it may even provide better throughput than mechanisms based on elevator disk scheduling. BubbleUp incurs a slight disk storage overhead, but we argue that through effective allocation, this cost can be minimized.