.. _multithread_datset: Multithread Dataset =================== It allows to perform an "experimental analysis of the impact of multi-threading on video encoding energy consumption". Download -------- .. code:: shell mendevi download multithread.db.xz.torrent * `multithread.json.xz `_ (1.2 Mo). * `multithread.db.xz.torrent `_ (5.8 Go). Plots ----- Power as a function of the logical core usage ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ .. code:: shell mendevi plot '' -x cores -y power -c '(profile, hostname)' -m encoder .. image:: /_static/media/multithread_cores_power.svg :alt: Power as a function of the logical core usage Logical core usage as a function of the provided number of threads ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ .. code:: shell mendevi plot '' -x threads -y cores -wx encoder -wy profile -c effort -m quality -f '"aerial" in name' .. image:: /_static/media/multithread_cores_threads.svg :alt: Logical core usage as a function of the provided number of threads Final energy as a function of the provided number of threads ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ .. code:: shell mendevi plot '' -x threads -y energy -wx encoder -wy profile -c effort -m quality -e '(threads, name)' .. image:: /_static/media/multithread_energy_threads.svg :alt: Final energy as a function of the provided number of threads Conclusion ---------- The more cores used, the faster the encoding, and therefore the less significant the static power consumption. The gain is therefore very high for a small number of threads. However, this gain becomes less significant when exceeding 8 threads. In addition, bit rate distortion decreases with the number of threads due to tiling. Thus, 8 threads seems optimal. Reproduce --------- .. code:: shell mendevi prepare -p sd netflix_aerial.mp4 mendevi prepare -p fhd netflix_aerial.mp4 mendevi encode reference* -e fast -e medium -n2 -t1 -t2 -t3 -t4 -t5 -t6 -t7 -t8 -t9 -t10 -t11 -t12 -t13 -t14 -t15 -t16 mendevi probe reference* sample*