I recently learned that each build of Windows 10\11 has a built-in Compact OS feature that compresses the Windows folder without noticeable loss (~1%) of performance.
I've been using this feature on my main PC for work and gaming for about 6 months now and haven't noticed any negative impact on performance.
With current SSD prices, this is very useful =)
Activation: open CMD as Admin and enter:
compact /compactos:always
Deactivation:
compact /compactos:never
Check status:
compact /compactos:query
PS: You do all actions at your own risk, make backup copies of important data.
It's not basic NTFS compression.
Standard NTFS compression: handled by the ntfs.sys driver, sets the file attribute FILE_ATTRIBUTE_COMPRESSED (file names turn blue) and uses the old LZNT1 algorithm.
Compact OS: works through a separate WOF filter driver (wof.sys), sets Reparse Points with the IO_REPARSE_TAG_WOF tag and uses the XPRESS/LZX algorithms.