Linaro alip releases 20.02 and 20.07 cause slowdowns and screen lock-ups

I experience screen lockups and significant UI slowdowns on Linaro releases 20.02 and 20.07. I had no such issue when using release 19.01. The situation seems to be worse on 20.02 where the Xorg server halts and pressing Alt+F1 takes longer than 5 minutes to switch to the console and ten it takes several minutes to login in terminal. In release 20.07 I can see a similar issue, the lock-up is less severe, the screen usually unlocks within tens of seconds. Entering the terminal screen (Alt + F1) is quicker as well (several seconds). What I observe in terminal are kernel messages like this:

wcn36xx: ERROR hal_enter_bmps response failed err=1
wcn36xx: ERROR Can not enter BMPS!
msm_gem_shrinker_scan: 6 callbacks suppressed
Purging 16384 bytes
Purging 221184 bytes

I’ve done apt update and apt upgrade, the issue is still there.
The issue happens ~after 30 minutes of browsing the web while connected via internal Wifi. Please note that using Chromium web browser is problematic as well, there are some severe scrolling issues preventing comfortable browsing. I’ve installed Firefox and it works OK, but after browsing a while some news pages like bbc.co.uk (20 - 30 minutes) the lock-ups occur.
It does not seem to be related to heat, when touching the SOC metal shield it is warm, but not hot.

I’ve been using release 19.01 and I did not see such issues there. So far the solution for me is to use the 19.01 release.

Look like the system is low in ram, browsers are usually memory-hungry, though it would not explain why it’s different with 19.01. can you share the htop output?

Thanks for the reply. Here is the htop screenshot when the lockup happened. One tab was opened it Firefox and it was the same site I wrote before.

Update: this time the lockup is permanent - the board did not ‘unfreeze’ itself into usable state as it did ibefore. But the linux is still running. The mouse cursor moves, but when I press Alt+Tab or Alt+F1 nothing happens. I tried to mouse click on various windows and start menu button and nothing happened - the windowing system is completely unresponsive. I pressed ScrollLock key on keyboard to check whether the LED is toggled and it is, so I guess the kernel is still running.

You’re very low in ram and there is no swap, so some components can appear frozen, though the system still running. The 410c has only one giga of ram, which seems limited for today browsers.

One thing you can try is enabling zram to create a ‘fast’ swap: https://www.96boards.org/documentation/consumer/guides/zram_swapspace.md.html which should improve the situation.

Thank you for your reply. The desktop is frozen and the whole system is unusable when that happens. I don’t think that’s normal Linux behavior. Mind you, no such thing happens on 19.01. I’ve used several Linux SBC with 1GB RAM in the past, but none of them froze the desktop when low on RAM.

Maybe you should compare memory usage then. and test with/without zram.