I recently upgraded from Ubuntu 16.04 to 18.04 -> 18.10 and 19.04 since I had problems with Ubuntu crashing/hard freezing, especially with lock screen or after sleeping.
The lock screen hard crashes are gone, but I have plenty of other issues instead.
In particular, every time I drag to open the "lock" screen it gets stuck and seems frozen, half way for 30-60 seconds before finally getting into Ubuntu (see image)
Also, whenever I create a new text file and save it for the first time, the GUI freezes completely for 30-60 seconds as well, before going back to normal. The same thing happens when saving a screen shot from the screenshot app, so it seems there is some problem with disk access? However, when saving to an existing file, there is no delay.
Any ideas what could cause these issues or how I can try to debug it?
Basic system info from the "About" tab:
Ubuntu 19.04
Memory: 15.4 GiB
Intel Core i7 8550U CPU @ 1.80 GHz x 8
Graphics Intel UHD Graphics 620 (Kabylake GT2)
Gnome 3.32.1
Os type 64-bit
Disk 512,1 GB