Possible separation of dentries and inodes from main used memory

[brauliobo]

Here is my htop current memory usage:

After clearing the page caches with echo 1 > /proc/sys/vm/drop_caches, I get:

So roughly the same green part, but less orange part indicating less cache, which makes sense.

After clearing dentries and inodes cache with echo 2 > /proc/sys/vm/drop_caches, I get:

Which shows 1.7gb less memory usage (from 23.8gb to 22.1gb), which doesn't make sense to me.

I guess that this issue of dentries and inodes caches being reported as non cache application memory is a Linux issue.

Still, I wonder if there is a way to correctly separate dentries/inodes cached memory from the main (green) used memory?