Methodologies for generating HTTP streaming video workloads to evaluate web server performance

Recent increases in live and on-demand video streaming have dramatically changed the Internet landscape. In North America, Netflix alone accounts for 28% of all and 33% of peak downstream Internet traffic on fixed access links, with further rapid growth expected [26]. This increase in streaming traffic coincides with the steady adoption of HTTP for use in video streaming. Many streaming video providers, such as Apple, Adobe, Akamai, Netflix and Microsoft, now use HTTP to stream content [5]. Therefore, it is critical that we understand the impact of this emerging workload on web servers. Unlike other web content, a recent study [13] of streaming video shows that even small infrequent latency spikes, manifested as buffering related pauses, can result in shorter viewing times especially during live broadcasts. Unfortunately, no appropriate benchmarks exist to evaluate web servers under HTTP video streaming workloads. In this paper, we devise tools and methodologies for generating workloads and benchmarks for video streaming systems. We describe the difficulties encountered in trying to utilize existing workload characterization studies, motivate the need for workloads, and create example benchmarks. We use these benchmarks to examine the performance of three existing web servers (Apache, nginx, and userver). We find that simple modifications to userver provide promising and significant benefits on some representative streaming workloads. While these results warrant additional investigation, they demonstrate the need for and value of HTTP video streaming benchmarks in web server development.