On 07/01/2025 11:22, Michel Dänzer wrote:
On 2025-01-07 10:29, Tvrtko Ursulin wrote:
On 06/01/2025 17:16, Michel Dänzer wrote:
On 2025-01-02 20:44, Tvrtko Ursulin wrote:
"vkgears -present-mailbox" average framerate:
Before: 21410.1089
After: 21609.7225
With a disclaimer that measuring with vkgears feels a bit variable,
nevertheless it did not look like noise.
That's ~1% difference. IME the frame rate can easily vary more than that during a single run.
The frame rate surely varies by more than 1 fps during each run, so comparing such large average values down to 4 digits after the decimal point doesn't seem very useful.
Doing multiple (at least 3 or more each) before & after runs and comparing the distribution of individual measured values using something like ministat might confirm it's essentially noise, or give more confidence it's not.
I did multiple runs and I thought from the code changes it would be obvious there is some code there which should go.
FWIW, I didn't question that, in fact I don't have any particular opinion on the actual code changes. Claims of performance differences based on two numbers are just a pet peeve of mine. :)
But fair enough, I agree ministat is common practice so I re-did it. Five ~100 second runs each kernel. Absolute numbers are a bit different before I turned on some kernel hardening options since.
x before
+ after
+------------------------------------------------------------+
| x + |
| x x + |
| x xx ++++ |
| x x xx x ++++ |
| x xx x xx x+ ++++ |
| xxxxx xxxxxx+ ++++ + + |
| xxxxxxx xxxxxx+x ++++ +++ |
| x xxxxxxxxxxx*xx+* x++++++++ ++ |
| x x xxxxxxxxxxxx**x*+*+*++++++++ ++++ + |
| xx x xxxxxxxxxx*x****+***+**+++++ ++++++ |
|x xxx x xxxxx*x****x***********+*++**+++++++ + + +|
| |_______A______| |
| |______A_______| |
+------------------------------------------------------------+
N Min Max Median Avg Stddev
x 135 21697.58 22809.467 22321.396 22307.707 198.75011
+ 118 22200.746 23277.09 22661.4 22671.442 192.10609
Difference at 95.0% confidence
363.735 +/- 48.3345
1.63054% +/- 0.216672%
(Student's t, pooled s = 195.681)
It's a small difference but every little helps.
This gives a lot of confidence in the performance gain, thanks! Would be great if you could incorporate at least a summary of this into a commit log somehow.
Thanks! Now lets hope someone can spare the time to review.
I pasted the graph into a reply to cover letter of v2 of the series.
That's my best idea since it is a series with a few small improvements
which add up to a total.
Regards,
Tvrtko