On 1/27/21 7:35 PM, Christian Hewitt wrote:
On 27 Jan 2021, at 3:11 pm, Lukasz Luba <lukasz.luba@xxxxxxx> wrote:
On 1/27/21 10:24 AM, Lukasz Luba wrote:
Hi Christian,
On 1/25/21 8:18 AM, Christian Hewitt wrote:
This patch adapts the panfrost pre-defined thresholds change [0] to the
lima driver to improve real-world performance. The upthreshold value has
been set to ramp GPU frequency to max freq faster (compared to panfrost)
to compensate for the lower overall performance of utgard devices.
[0] https://patchwork.kernel.org/project/dri-devel/patch/20210121170445.19761-1-lukasz.luba@xxxxxxx/
Signed-off-by: Christian Hewitt <christianshewitt@xxxxxxxxx>
---
I have been using Kodi as my test application. If you scroll in library
views with hundreds of list items and the panfrost values the slow GPU
ramp up is quite noticeable and the GUI feels sluggish. As everything
lima runs on is inherently slower than panfrost using devices I believe
it's better to ramp up to max freq quicker.
It's quite low value for the upthreshold, but I believe you have
experimented and observed that a bit higher (30, 40?) don't work well.
I don't know the Kodi system, though.
You can check if the other frequencies are also used in statistics for
devfreq device:
cat /sys/class/devfreq/<your_gpu>/trans_stats
If they are also used, then it OK (better than stuck at min freq).
I've just realized that your board might suffer a another issue.
Please apply this patch [1] and run your experiments with upthresholds.
[1] https://lore.kernel.org/lkml/20210127105121.20345-1-lukasz.luba@xxxxxxx/
I’ve included the patch and with unscientific testing it feels snappier with a larger value than
before. I did revert back to 45 first, but again this feels sluggish when navigating around the
Kodi GUI. My main test is to enter ‘Movies’ in Kodi then start scrolling in a long list. When
the GPU ramps up quickly the experience is snappy, but when it ramps more conservatively
scrolling feels like it stutters, then (once you hit max freq) it becomes fluid.
WP2:~ # cat /sys/class/devfreq/d00c0000.gpu/trans_stat
From : To
: 125000000 250000000 285714285 400000000 500000000 666666666 744000000 time(ms)
* 125000000: 0 0 0 0 0 0 264 52720
250000000: 9 0 0 0 0 0 36 3404
285714285: 9 3 0 0 0 0 32 2628
400000000: 18 20 13 0 0 0 191 21140
500000000: 12 12 8 63 0 0 31 10068
666666666: 179 5 16 133 66 0 24 29360
744000000: 37 5 7 46 60 423 0 46016
I’ll send v2 with the value set to 30.
Thank you Christian for re-testing it and attaching the stats. It looks
good. I'll add my reviewed-by for v2 patch.
Regards,
Lukasz
_______________________________________________
dri-devel mailing list
dri-devel@xxxxxxxxxxxxxxxxxxxxx
https://lists.freedesktop.org/mailman/listinfo/dri-devel
