Who says your filesystem isn't compressing data under you? Actually, who says the disk itself isn't?
(Sometimes they both are.)
(Sometimes they both are.)
Me, because we don't use transparent compression anywhere.
> Actually, who says the disk itself isn't?
I'm not very sure about that, to be honest. SSDs do that to prolong their life, but the saved space doesn't return as more space on FS level. It just returns as endurance, which is more important in my case.
So, disk's transparent compression doesn't mean very much from a sysadmin/OS operations perspective.
Since Fedora 34, a clean install will result in btrfs with zstd compression turned on. (An update of an older install will of course not change the filesystem from underneath the files.)
Other systems we install are configured on many levels, so even if the defaults are BTRFS w/zstd, it might be either known or changed to suit our needs better.