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Bcachefs may be headed out of the kernel

(lwn.net)
144 points ksec | 4 comments | 04 Jul 25 13:32 UTC | HN request time: 0.865s | source
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msgodel ◴[04 Jul 25 17:53 UTC] No.44466535[source]▶
The older I get the more I feel like anything other than the ExtantFS family is just silly.

The filesystem should do files, if you want something more complex do it in userspace. We even have FUSE if you want to use the Filesystem API with your crazy network database thing.

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anonnon ◴[04 Jul 25 18:10 UTC] No.44466685[source]▶
> The older I get the more I feel like anything other than the ExtantFS family is just silly.

The extended (not extant) family (including ext4) don't support copy-on-write. Using them as your primary FS after 2020 (or even 2010) is like using a non-journaling file system after 2010 (or even 2001)--it's a non-negotiable feature at this point. Btrfs has been stable for a decade, and if you don't like or trust it, there's always ZFS, which has been stable 20 years now. Apple now has AppFS, with CoW, on all their devices, while MSFT still treats ReFS as unstable, and Windows servers still rely heavily on NTFS.

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1. zahlman ◴[04 Jul 25 22:31 UTC] No.44468462[source]▶
... NTFS does copy-on-write?

... It does hard links? After checking: It does hard links.

... Why didn't any programs I had noticeably take advantage of that?

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2. anonnon ◴[04 Jul 25 23:21 UTC] No.44468793[source]▶
> NTFS does copy-on-write?

No, it doesn't. Maybe you're thinking of shadow volume copies or something else. CoW files systems never modify data or metadata blocks directly, only modifying copies, with the root of the updated block pointer graph only updated after all other changes have been synced. Read this: https://www.qnx.com/developers/docs/8.0/com.qnx.doc.neutrino...

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3. zahlman ◴[05 Jul 25 01:05 UTC] No.44469318[source]▶
>No, it doesn't. Maybe you're thinking of shadow volume copies or something else.

I was asking, because didn't know, and I thought the other person was implying that it did.

I know what copy-on-write is.

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4. anonnon ◴[05 Jul 25 02:11 UTC] No.44469587{3}[source]▶
The "other person" (only mention of NTFS) is me, here:

> while MSFT still treats ReFS as unstable, and Windows servers still rely heavily on NTFS.

By this I implied it's an embarrassment to MSFT that iOS devices have a better, more reliable file system (AppFS) than even Windows servers now (having to rely on NTFS until ReFS is ready for prime time). If HN users and mods didn't tone-police so heavily, I could state things more frankly.