Minimizing Memory Requirements in Media Servers

Abstract

Poor memory management policies lead to lower throughput and excessive memory requirements. This problem is aggravated in multimedia databases by the large volume and real-time data requirements. This study explores the temporal and spatial relationships among concurrent media streams. Specifically, we propose adding proper delays to space out IOs in a media server to give more room for buffer sharing among streams. Memory requirements can be reduced by trading time for space. We present and prove theorems that state the optimal IO schedules for reducing memory requirements for two cases: streams with the same required display rate and different display rates. We also show how the theorems can be put in practice to improve system performance. Keywords: multimedia, disk scheduling, memory requirement.