Does Windows use RAM when copying files?

Question

Windows

I noticed that sometimes, when interacting with files immediately after copying them, the interaction goes too fast. Also, when copying from a fast disk to a slow one (SSD->HDD), reading files ends before they are written.
Do I understand correctly that the file system stores the last data affected by it in an unclaimed part of RAM for some time?

Answer 1

Copying is reading and writing the contents of files. Disks do not know how to independently transfer data bypassing RAM. It is quite natural that the data remains in the file cache with some probability. But at the expense of lack of demand, everything is not so simple here, because data from some file may turn out to be more necessary for the memory of some application. In this case, the kernel can throw it into the swap, and store the cache of files in memory. Unfortunately, the situation when the OS incorrectly prioritizes is quite common and tens of gigabytes of memory is not a panacea for this problem at all.

Answer 2

reading files ends before writing them

HDD write caching is most likely enabled. So, you can’t do without using RAM, but the OS tries to complete file operations as quickly as possible in order to avoid data loss.

Answer 3

The entire transfer is processed by the processor, but something is cached in RAM, although there may still be a data fragmentation factor on the HDD