SSD HDD - there is more real space than is written in the system! How to win?

Question

Solid State Drives

Hello connoisseurs!
The essence of the story is this - we go into the PC (win7) writes, free on HDD 20 gig out of 120 (i.e. 100 gig is occupied)
We go into the only drive C through Explorer, display all hidden and system folders - we see that in total all files on C occupy 40 gig.
The question is, what is it? What suddenly eats +60 gig? In fact, the PC thinks that 100 is occupied ...
SSD exists as a single partition, the cluster size is default, which was set by Windows during installation.

Answer 1

Yes, whatever.
For example, how did you measure the size of the System Volume Information folder?
It always shows 0 bytes in explorer. But in reality, depending on different settings, it can be from several hundred bytes to several terabytes. Where do you think ShadowCopy is stored? Or storage of chunks, and other interesting things.
Determining the used disk space is a rather ambiguous process, depending on how you calculate it.
For example, on a disk with a capacity of 2 terbytes, the total size of all data is 8 terbytes, and only 500 gigabytes are free.

Answer 2

I saw when the swap file + hibernation file ate 50 GB of space. If you have a lot of RAM (16 GB or more), pay attention to hiberfile.sys and pagefile.sys in the root of the disk (to see them, uncheck "hide system and protected files" in the same place where you turn on the display of hidden files and folders)
Reducing the paging file is configured in the advanced properties of the system, hibernation - in the power settings
. The "disk cleanup" function in the system can also help. Programs often store temporary files and don't rub them. (C:/Users/username/AppData/Local/Temp - and in general, take a look at the size of AppData itself. Again, only visible if you check that box)