Since deleting a RAM management app on my MacBook Pro, it hasn’t had anything like the memory pressure it used to suffer from. Previously it would sit around with a few hundred MB of free RAM & generally have three swap files of 1.07 GB each in Virtual Memory.

Now it generally has at least 1.4 GB of free RAM & just one of those swap files.

About a week ago, for no logical reason, it became very slow & started creating swap files every minute until I shut it down with 27 swap files on board.

Rebooted into an ext SSD with TechTool Pro on it & checked the directory for corruption, passed as OK. So I ran a few other TTP checks, which it also passed.
Booted normally, started creating swap files again but this time stopped at 12 of them, still too. many & still slowing the machine down too much.

Next, I booted into a recent clone on another ext SSD & restored the Mac to the state of that SSD as it was operating correctly. That took about 15 minutes with Super Duper app & it’s been quite well-behaved ever since.