Multiple apps slow to a crawl after a KVM switch

[zsilet]

In summary, I am noticing that multiple apps will become almost completely unresponsive after I use my KVM switch to leave, then return to pop_os. I have to minimize and restore the apps in question, after which they work as normal.

My setup is a laptop connected to a second monitor. KVM will switch keyboard/mouse/second monitor, while laptop screen stays active. On the second (switched) monitor, I have VSCode in one tile, while cosmic files / cosmic text, browser etc in a stack in a second tile.

I switch the KVM away, then back to the laptop, and often times I can observe that text input to VSCode/Cosmic text is unresponsive, and clicking/opening files in cosmic files is also unresponsive. This condition persists until I minimize the affected application/stack of applications. Once I restore them, the issue is immediately resolved.

Not all applications seem to be affected. For example, PCMan File Manager never shows the issue (whereas COSMIC files does so often).

I am happy to collect any additional information as necessary.

[jacobgkau]

Booting, recreating the issue, then running sudo journalctl -b 0 > logs.txt to generate a log file might help the developers know what's causing this.

[zsilet]

Adding journalctl log.
I switched away from pop_os around 12:00.
I switched back to pop_os right around 12:38:12, where the logs show my mouse and keyboard being re-detected. At this point I noticed my tilix session was unresponsive (would take 2-3 seconds for each keystroke to be recognized). I initiated the attached log from this tilix session.
Again, minimizing and restoring the window immediately fixed the issue (done after logs were taken.

The logs show a number of removable drive connect/disconnects while I was not using the computer. This is because I have a microprocessor dev kit attached (for my dayjob) that I power cycled a few times. I am not sure this is related, I will disconnect it though next time I switch away, so it doesn't interfere/cloud the issue. I will also disconnect the QL-800 printer next time around.

log.txt

[zsilet]

Here is a video of the issue, as well as an additional log, from the time I switch away from pop-os to the time I switch back.
https://photos.app.goo.gl/Vm2CyTAvojyTBq7b6

log2.txt

[GilesBrule]

I can confirm this behavior. Browsers Edge and Floorp do this for sure, possibly other apps. This also happens if my laptop is undocked; close the lid and connect it to my KVM. Up until I saw this post, I had been closing the app to fix it, but minimizing and restoring does fix the problem.

[zsilet]

Just a quick note that this issue is still reproducible on the latests popdev:master version.

[ids1024]

I've noticed this behavior sometimes without output hotplug. Though it doesn't seem to be consistent.

This would likely be an issue with Wayland frame callbacks. For some reason cosmic-comp isn't properly sending them for the new monitor the window and workspace are on, so they're throttled to 1/second.

[ids1024]

I think I've figured out what's going on here, and pop-os/cosmic-comp#990 should finally fix it.