I want to share my personal experience in this issue as it may well happen to others and I don't want you to go through all I did. loll
I have spent almost 12hours reading and testing and validating in order to pinpoint a 5-8FPS drop I was consistently getting every 5 sec, which was causing frame drops/freezings and made video streaming a bad experience, as well as freezing the mouse cursor a few msec every 5sec.
It was like that in Dr460nized and then I took my test HD with KDE Multimedia installed and damn I had the same issue, although it was less important and at every 8sec intervals.
It seemed XRENDER was almost getting rid of this, but openGL was hit bad.
I was about to get crazy. This was fine when I tested Garuda before using it and the issue started a few days ago. I thought it could be nvidia driver updates, kernel updates, etc...
My hardware is not low end: Ryzen 3700x, 16Gb, lots of fast enough HDs with space, nvidia GTX 1650, 4K 60FPS monitor and very low and controlled temperatures all around the machine. I do not do gaming either. And since when I boot from Kubuntu subvolume all is smooth with same nvidia driver and configuration, I knew it wasn't the hardware.
Well out of nowhere during my lunch time I decided to look at the problem from a different tack. Maybe I should look around for what I have on my system that occurs every 5sec?
The obvious place to look at was Conky. I have added to the default Garuda Conky theme a bunch of data for my video card. Clock Speed, Fan Speed, Fan Load, GPU Usage, Mem Usage, Mem Speed... most of them use
nvidia-smi to poke the data from and one uses
nvidia-settings. All of them are poked every 5sec.
Then there is the CPU TOP processes at the bottom, and CPU freq/load at the top, but they aren't at every 5sec. Still who knows.
There was also HDDTEMP every 5 sec.
I decided to comment out one by one and once I got to the video card data I commented them out.
BAM! 59-62FPS steady, no more drop, no more freeze!
Then I uncommented them out one by one and it seems the more I had using nvidia-smi, the worst the FPS drop/freeze gets.
It's posible my lines in Conky are wrong, I'll look into that later, but at least I know this type of processing could cause you FPS drops. even with a fast machine and no CPU used.
I can now have fun again using Garuda!
Just I'll be more careful when I change stuff.