Comment 50 for bug 1833281

I can confirm this regression. My system does not freeze with 4.9.140 and is overall totally usable on high memory usage and swap (right now 7.5 out of 8 GB RAM is used and 2 GB is swapped), but it becomes unresponsive with 4.19.10 when memory consumption is close to my RAM limit of 8 GB.

My system is:
Lenovo Thinkpad X220 laptop, Intel Core i7-2640M CPU (Sandy Bridge), Intel HD 3000 GPU, 8GB RAM, 8GB SWAP, SSD, UEFI mode.
Fedora 29, kernels 4.9.140 (self-built), 4.19.10-300.fc29.x86_64 from repository.
I'm using KDE Plasma 5.

You can easily reproduce this issue with the following steps:
1. Add "mem=2G" to the kernel command line. If you use GRUB, press "e" button in the bootloader menu and append "mem=2G" to the "linux" line. Your system would be limited to 2 GB RAM.
2. Boot the system (press F10 in bootloader menu after editing)
3. Run several heavy applications: web browser, word processor, GIMP. Open gmail web interface in browser, it's also heavy.

Expected result:
The system (at least the GUI, including mouse cursor) does not freeze/hang, but properly utilizes swap, what could be seen with 4.9.140 kernel (before regression). System is usable, all applications are still accessible, the music plays without hiccups, you can continue doing your work.

Actual result:
The system (at least the GUI, including mouse cursor) freezes/hangs with 4.19.10 kernel, with a very little chance to recover by itself. Disk activity LED is constantly lid. System is unusable.