Final Project - Stage 1 Report (Follow Up)

This is a follow up from the previous report on stage 1. The reason for this follow up was that I had a discussion with my professor on what I was doing for stage 1 for this project. The main takeaways were that I should use a bigger video file for testing and that I should use the built in "time" command for testing execution time instead of a manual stopwatch.


Initially wanted to use a bigger video file with my use case however I encountered several issues that prevented me from doing it. One, was that I tried to use "Handbrake" to convert an mp4 file I had to a .264 file. Unfortunately, no such option existed, so instead I tried to use the built in encoder in openh264. That lead to me to using ffmpeg to convert a mp4 to a .yuv file. Sadly though, no success came from that avenue either. This in turn did not allow me to redo my testing with a bigger video file.


The only recommendation I was then able to follow was to use the "time" command for measuring execution time and luckily this came with success. By using this method instead of a manual stopwatch I was able to get accurate measurements from both the program's side as well as the system operation side.

Note the test code from the previous stage 1 report was used.

The results: https://gist.github.com/Megawats777/6ce232ad0c186427a71ee1f0f52d8f7d


What stood out too me from these new found results was the following. First, is that when comparing the machines there is a very clear difference who is the better performer. On the arm_64 side the aarchie machine seems to lag more and more behind when compared to the bbetty machine. While on the x86_64 side xerxes keeps blowing my PC running a VM out of the water. A clear indicator of this is that xerxes has it's performance mostly measured in seconds while my PC's performance is measured in minutes. The second aspect that stood out was the performance degradation as less code optimization was applied. A machine that was greatly affected by the reduction in code optimization, was aarchie. For instance, the transition from opt. level 3 to 2 meant a 3-4 second increase in execution time. While the transition from opt. level 2 to 1 meant an approximately 25 second increase in execution time. The last aspect that stood out to me was when I was testing out my PC vm running Fedora the first test was sometimes 10+ seconds faster or slower when compared to the second test. 


Thank you for reading and hopefully this time see you in stage 2.