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johncolanduoni 2 days ago

What warranties? I assume you’re comparing it to ext4 and not e.g. ZFS?

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speed_spread 2 days ago | parent [-]

Here are a few

- mandatory byte-range locks enforced by the kernel

- explicit sharing modes

- guarantees around write ordering and durability

- safe delete-on-close

- first-class cache coherency contracts for networked access

POSIX aims for portability while NTFS/Win32 aims for explicit contracts and enforced behavior. For apps assuming POSIX semantics (e.g. git) NTFS feels rigid and weird. Coming the other way from NTFS, POSIX looks "optimistic" if not downright sloppy.

Of course ZFS et al. are more theoretically more robust than EXT4 but are still limited by the lowest common denominator POSIX API. Maybe you can detect that you're dealing with a ZFS backed volume and use extra ioctls to improve things but its still a messy business.

	▲	johncolanduoni a day ago \| parent \| next [-]
		These are pretty much all about mandatory locking. Which giveth and taketh away in my experience. I’ve had substantially fewer weird file handling bugs in my Linux code than my Windows code. POSIX is very loosey-goosey in general, but Linux’s VFS system + ext4 has a much stronger model than the general POSIX guarantees. `FILE_FLAG_DELETE_ON_CLOSE`’s equivalent on Posix is just rm. Windows doesn’t let you open new handles to `FILE_FLAG_DELETE_ON_CLOSE`ed files anyway, so it’s effectively the same. The inode will get deleted when the last file description is removed. NFS is a disaster though, I’ll give you that one. Though mandatory locks on SMB shares hanging is also very aggravating in its own right.
	▲	pjmlp 2 days ago \| parent \| prev [-]
		Also to point out that outside UNIX, surviving mainframe and micros, the filesystems are closer to NTFS than UNIX world, in regards to what is enforced. There is also the note that some of them are more database like, than classical filesystems. Ah, and modern Windows also has Resilient File System (ReFS), which is used on Dev Drives.