Gemini Lake Laggy UI and GPU Frequency Scaling

    I recently acquired a HP T430 Thin Client with an Intel Celeron N4020 CPU. Running a clean install of Libreelec 12 on it, I can notice that there are clearly some dropped frames while navigating through the menus. Enabling the logging setting shows an FPS in the 20-30s range. The reason I even got this system was that x86 machines are reportedly much smoother and faster than arm machines for minimal kodi boxes.


    There's been a bunch said already about this on the internet, and the solution has been to force the minimum gpu frequency to the max value supported.

    111032 – Need to set gt_min_freq_mhz to max value to avoid sync issues on Gemini Lake N5000/J5005

    Conservative frequency drops frames on Gemini Lake (#2197) · Issues · drm / i915 / kernel · GitLab
    Issue I think the frequency scaling is slow on Gemini Lake and it drops some frames on desktop animations. (I submited...
    gitlab.freedesktop.org
    Post

    RE: CPU stuck at 800Mhz?

    Yeah, setting GPU frequency to a max.setting is pretty much a must for most Intel LE boxes. I use 750 mhz GPU speed for my Gemini Lake box. However, I didn't have to change the CPU governor to "performance" because default "powersave" seem to work fine for me.
    smp
    July 28, 2019 at 2:37 AM
    Post

    RE: Video stutter 25Hz Videoplayback with Hardwaredecoding Libreelec 9.0

    Ok, more experimenting...and I think I have beaten it (or more to the point Ross Nicholson has it cracked, here: 111032 – Need to set gt_min_freq_mhz to max value to avoid sync issues on Gemini Lake N5000/J5005)

    It seems this is (still) the problem. The GPU clock speed is not scaling up as it should under load.

    With a NUC 2820, I added this `autostart.sh` script:

    (Code, 5 lines)

    The 750 comes from the output of this command (you should check if you have a different NUC)

    (Code, 1 line)

    This results…
    bossanova808
    July 27, 2019 at 6:36 AM


    The lack of further responses to any of the above tickets seem to indicate that the issue no longer exists, but it's clearly present for me. Is this a linux kernel issue or a buggy bios/firmware for my device?


    I know I haven't posted any logs here, and it's because I wasn't sure what exactly to put. If the devs want something particular to look at, please let me know.


    Sidetrack: I tried to do some further testing running kodi wayland in ubuntu desktop. I could swear that I noticed that the UI was buttery smooth when the default audio device wasn't HDMI, and only started dropping frames when I changed the the output device to HDMI audio in gnome settings. I tried replicating this a few more times to get some logs, but couldn't get it to consistently reappear. dmesg and journalctl logs didn't show anything either. If anyone has thoughts on this, please let me know.

    Edit: Just to add, the gpu frequency hack seems to mostly fix things to for me. My question is about whether we have a clearer understanding of the bug and whether it can be fixed upstream somewhere.

    i'm using the same device, with N4000 CPU. therefore i want to ask for the result.

    i cannot confirm the described behaviour with dropped frames at the KODI GUI, but i like to have optimized LE for t430.

    did you compile a custom image without 'projects/Generic/patches/kodi/000-temp-revert-fences.patch' ?

    and did you changed the GPU frequency?

    thanks in advance.