Microarchitectural Performance Evaluation of AV1 Video Encoding Workloads

Abstract

Video encoding/decoding is an extremely relevant workload in our society today. Videos account for a significant percentage of the world’s network traffic, which is expected only to be growing. Thus, it is important to understand these workloads to optimize the hardware to handle them better.This paper explores the reasons for the large runtimes taken by AV1 encoding workloads. We discover that the runtime of the SVT-AV1 encoder is significantly higher than other encoders because it requires a larger number of instructions to encode the same video, rather than any significant microarchitectural inefficiencies. We also compare the thread scaling of SVT-AV1 against other codecs and observe that SVT-AV1 contains the highest degree of parallelism of the tested encoders.