Distributed Schedule Management in the Tiger Video Fileserver

ACM SIGOPS Operating Systems Review 02/2004; 31(5). DOI: 10.1145/268998.266692
Source: CiteSeer


Tiger is a scalable, fault-tolerant video file server constructed from a collection of computers connected by a switched network. All content files are striped across all of the computers and disks in a Tiger system. In order to prevent conflicts for a particular resource between two viewers, Tiger schedules viewers so that they do not require access to the same resource at the same time. In the abstract, there is a single, global schedule that describes all of the viewers in the system. In practice, the schedule is distributed among all of the computers in the system, each of which has a possibly partially inconsistent view of a subset of the schedule. By using such a relaxed consistency model for the schedule, Tiger achieves scalability and fault tolerance while still providing the consistent, coordinated service required by viewers.

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    • "In contrast, a long cycle length makes it possible that more streaming sessions can be served concurrently, while startup latency becomes long and the quality of each streaming session is reduced. Most previous studies [8]–[10], [14], [16] that adopted cycle-based disk scheduling with fixed cycle length did not examine which cycle length was the most cost-effective. In this section, we present a method to find the most cost-effective cycle length. "
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    ABSTRACT: This paper discusses several practical issues related to the provision of video-on-demand (VOD) services, focusing on retrieval of video data from disk on the server. First, with regard to system design, the pros and cons of cycle-based scheduling algorithms for VOD servers are compared, and an adequate policy according to system configuration is presented. Second, we present a way to tune the cycle-based scheduling algorithm so that it maximizes profit. Third, a method to overcome the cons of cycle-based scheduling algorithms is proposed, and its cost is analyzed.
    Preview · Article · May 2005 · IEICE Transactions on Communications
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    • "There are numerous prototype file systems which are designed to handle multimedia data. Tiger Shark is a scalable, parallel file system designed to support interactive multimedia applications, particularly large-scale ones [7][6]. MMFS [4] improves interactive playback performance by supporting intelligent prefetching , state-based caching, prioritized real-time disk scheduling, and synchronized multi-stream retrieval. "
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    Full-text · Conference Paper · Jan 2004
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    • "Secondly, as nodes are added to a server, existing content must be redistributed. Many architectures also require that each sever node has an identical hardware configuration (Bolosky et al., 1997). Finally, the failure of any single node will lead to the loss of all streams, unless redundant data is stored (Wong and Lee, 1997). "
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