Please see the Known Issues and Solutions section (available in every Update announcement topic); there are several items that might be related;
Also, read through the comments;
I notice there is at least one with a similar description to your issue.
Regards.
I notice you have no swap space configured; you might wish to attend to that when you are able.
A safer method than a hard reset (to shutdown your machine) is described here;
This is generally recommended for a frozen computer. In your case, the machine isn’t frozen, but REISUB/REISUO remains a recommended alternative to a hard reset.