I had a problem similar to what’s described in this thread: https://www.reddit.com/r/Fedora/comments/dyoc5h/fedora_31_interactive_performance_regression/
The display would freeze and pause for seconds at a time (sometimes up to 10 or 20 seconds) and the mouse would be choppy. If I were in the middle of typing, when the system resumed, I’d get many repeats of whatever character had been delayed.
top would show that kswap0 was eating CPU when the pauses happened. I am on a laptop with SSD, so this is odd-- swap has a bandwidth > 100+MB/s with negligible seek, so that’s a lot of pages.
I followed the thread and found another reddit thread about 5.3+ (except 5.3.14+) and 5.4+ being buggy with intel iGPUs: https://www.reddit.com/r/linux/comments/e92p0e/psa_linux_53_except_5314_and_54_have_issues_with/ .
I was running kernel 5.3.15, and I think the pauses had been happening since the last kernel upgrade to 5.3.14. So I said, well, maybe my problem is the inverse, so I rebooted to an earlier kernel 5.3.12-300.fc31.x86_64, and poof, the problem is completely gone. This is not to say it never pauses, but now the pauses are infrequent and last less than a second, even under load and memory pressure.
I am running an early 2015 Dell XPS13 with the i7-5500U and Intel HD5500 gpu.
Just sharing because I couldn’t find much other info on the same problem and the suggestions (add a kernel flag, switch to xorg) in the earlier thread were unsatisfactory to me. The kernel switch is fine. I locked my kernel with versionlock and will hold onto this kernel version. I was going nuts with the freezes (10 seconds every 10-20 minutes would drive anyone nuts, no?), so I just wanted the info to be out there.
(probably, didn’t retest) faulty: vmlinuz-5.3.14-300.fc31.x86_64
definitely faulty: vmlinuz-5.3.15-300.fc31.x86_64