SSD cache behavior

[giacomoleopardo]

Hi everybody, since I don't know shoot about cache behavior, I was wondering if this is normal.

Here's the scenario:

- DSM version  DSM 6.2.3-25426
- Loader version and model: JUN'S LOADER v1.04b - DS918+
- Using custom extra.lzma: IG-88's extra and extra2
- Installation type: BAREMETAL - ASRock Fatal1ty Z170 Gaming-ITX/ac, Intel Pentium G4400 SkyLake, 2x4 GB DDR4 RAM

- JBOD Volume for testing with:

    - HDD Toshiba 300 GB
    - HDD Hitachi 240 GB
- Read/Write Cache:
    - SSD Intel 120 GB
    - SSD Crucial 120 GB

 

Well, as soon as I build the cache, the Hit Rate basically stays at 100%.

So through Video Station, I played an HEVC 8 bit movie in background (second window of Safari)

Taking a look at Memory Resource Monitor, I noticed Free RAM size is decreasing while Cache RAM size is increasing up to almost the max value.

Here's a little video of what's happening (just 63 seconds, not much)