I recently installed the latest version of StoreMi (18.104.22.168) and configured it to use a 500 GB SATA SSD with an my 8TB hard drive which is used as a Steam drive. I launched several large games and saw the Cache size tick up to 0.1%, but, no matter how many different games I launch, the cache does not increase in size. Also, after launching several games and timing how long they take to load the first level, I rebooted and tested again with no apparent decrease in load times.
From what I understand, StoreMi is supposed to cache files on my hard drive as they are read so the next read will be faster. Am I misunderstanding how it works or is something else going on here?
Yes, it is suppose to cache the frequently used data onto the Cache.
What you can do is a quick test to see if the caching is working or not.