Improved multimedia server I/O subsystems

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A Measurement Based Memory Performance Evaluation of Streaming Media Servers

While a number of studies have focused on storage subsystem performance, in general very few studies have explicitly focused on the memory subsystem performance of streaming media servers. We carried out measurement-based study of the memory performance of two leading streaming media servers: Darwin streaming server and Windows media server. Our goal is to determine the specific conditions under which onchip cache or main memory becomes major bottleneck on the performance of these streaming media servers. Our measurement-based analysis indicates that with large number of client requests and high encoding rate (300kbps), the memory performance degrades significantly, leading to excessive number of cache misses and page faults which leads to throughput degradation and client timeout. Windows media server exhibits better cache performance and reports higher throughput. However, Darwin streaming server has lower page fault rate at 300kbps encoding rate and multiple stream distribution