Recommended SSD size to use as a L2 cache

[Taylor7500]

As the title says, I'm looking to set up a level 2 cache on an SSD to handle my 8TB HDD. Neither of these are my boot drive, if that's important.

In short I use my PC mostly for work and gaming, with data in the form of a few movies and TV shows stored there too. Due to their large install sizes, all my hefty programs and games are run off of the HDD so I was recommended elsewhere to use software such as PrimoCache to set up a tiered storage solution to get closer to the speed of an SSD with the data capacity of my HDD. However I don't know much about storage systems so figured I'd ask for help hammering out the specifics of what would work best for me. As far as I can tell, the smallest easily available SSD sizes are 128GB and 256GB - would a drive of that size be suitable to format as a cache?

If I understand correctly, the basic principle of this solution is for the software to figure out what programs I use most frequently, copy them onto the SSD and load them from there. Assuming that's true, if I am using a game with an install size in excess of 120GB, does that mean that a 120GB SSD used as a cache would not act as effectively as a 240GB, for example? Or is it handled in such a way that it wouldn't be a problem?

Similarly, are there any particular features or numbers to quote when looking for a suitable drive? I've been told to make sure I get an SSD with a DRAM cache but beyond that is there a particular feature I should be looking out for?

Also, for this setup are there any particular settings I should set in the software to help optimise my experience? I'm told that the default ones work well enough but if there's anything specific which would help I'd much appreciate it.

Thanks.

[Support]

Generally speaking, bigger cache size, better performance. This is because with bigger cache size you can cache more data. In a particular environment, I cannot recommend a SSD size because I don't know how much data are often accessed. For eg. Let's say you only store and access 100GB data in the 8TB HDD, then a 128GB cache of course is enough. However, if you often access 4TB data in the 8TB HDD, then the performance is not as good as that in the first example.
You may check the PrimoCache statistics "Free Cache (L2)" and "L2Storage Read". When "Free Cache (L2)" value is close to 32MB, it means that cache is full and PrimoCache will replace old cached data by new one by its replacement algorithm. The percentage value in "L2Storage Read" is the L2 cache hit rate, higher value means better L2 cache performance.