[Help] Memory report doesn't cover the whole memory in usage

I am writing a much simpler version of XCOM and trying to learn it with neural networks.
I experience a very big increase in memory when I simulate games that are self played. In 20 minutes it goes from 1,3GB to 5GB and after 2 hours computer restarts because it is out of memory (I have 16GB ram).
What I do:
-I simulate a bunch of games and delete actors very often(In 20 minutes I delete and respawn around 1000 actors) but they seems to be deleted correctly.
-I have some big arrays , around 5 2D arrays(float) of size 2000x70, 2 3D array of size 200x64x64(int32). I empty and fill them every time they are filled up (happens in around 10mins).But all in all, I don’t think they can eat up to 12GB of ram.
-At around 10 mins I save all the arrays mentioned on the disk.
-I don’t have any textures or custom meshes, just a landscape of 10000x10000, some basic blocks and 8 3rdPersonCharacter.

I constantly have around 70000 of objects but memory is always growing. I also force garbage collector at around 10mins.

I leave to you my memreports from before starting the game(1.3GB Mem used) and after 20 mins(5GB Mem used). Unfortunately I didn’t spot any object with large memory consumption so I still don’t have a clue.

Sorry for my lack of experience, my English and thank you in advance!