An effective video block placement scheme on VOD server based on multi-zone recording disks

Abstract

Proposes an efficient video block placement scheme of MZR (multi-zone recording) disks and evaluates its performance through a simulation model of a VOD (video on demand) server. The proposed placement scheme considers both the current disk products that have MZR characteristic and users' skewed access patterns for some popular videos. Popular video blocks of higher access rates are placed in outward zones, which have high bandwidth and sufficient space. To verify the proposed scheme, we tested its performance on a workstation which has two MZR disks while varying the skew factors. In addition, we formulated the transfer rate of a MZR disk, analyzed the theoretical maximum number of users supported and the required buffer size for each user on the proposed schemes. On performance evaluations, we considered the disk head scheduling, block placement methods and striping units. A series of experiments have shown that the proposed scheme considering the seek time and transfer rate of MZR disk is effective and can support more requests.