So, since ages I have been told that hard disks (I am specifically interested in HDDs and not SSDs) write data in units of 512 bytes, sectors. But when I interrogate the folder with stat . then I get told that blocks are 4096 bytes. How do I find out the sector size for the HDD and not the filesystem?
$ stat .
Plik: .
rozmiar: 4096 bloków: 8 bloki I/O: 4096 katalog
Urządzenie: fd01h/64769d inody: 58327220 dowiązań: 8
Dostęp: (0755/drwxr-xr-x) Uid: ( 1000/arkadiusz) Gid: ( 1000/arkadiusz)
Dostęp: 2021-12-21 18:53:44.275157484 +0100
Modyfikacja: 2021-12-16 23:35:35.206793831 +0100
Zmiana: 2021-12-16 23:35:35.206793831 +0100
Utworzenie: 2018-09-09 04:23:32.113656998 +0200
Wiki clearly states that 512-byte sector is the normal, unless we are talking about Advanced Format standard of 4K (4096 bytes).
As per comment: use sudo fdisk -x /dev/sda to get all the info you are looking for.