Is anything out there now comparable? Have we surpassed BeFS? Any residual functionality that contemporary filesystems lack?
Spotlight on OS X supports similar metadata storage and querying, but it's built on top of HFS+, not directly into the file system (and surprise, was built by Dominic Giampaolo, who worked on BeFS, author of the linked book).
WinFS claimed a lot of similar features shortly after Be was acquired, but to my knowledge, no file system has provided similar features _and_ had spextensive application support to leverage them.
Almost every filesystem "supports metadata", and while I agree that application support could be better, I think the real key is getting users to use that space themselves.
That means there's no way to do a query like "file type = audio/mp3" without either walking the filesystem or querying a separate index, which removes a lot of the benefits.
¹ I am not sure about this, but https://msdn.microsoft.com/en-us/library/windows/desktop/aa3... seems to suggest it
As for BeFS itself, it was a pretty awesome FS. I remember I used to use a utility called MP3 Army Knife, which could copy MP3 metadata to BeFS attributes. I then used Marco Nelissen's SoundPlay (shareware which I bought) to play them; basically using Tracker or BeFS queries to generate playlists.
I miss that OS.
Seconding things: BeFS was staggeringly fast – doing a simple query in something like Outlook or Mail.app is still nowhere near the same class as either the standard BeOS mail client or PMMail, even with generations of hardware improvements. On an idle system with an SSD, a Spotlight or Windows Search / Cortana query isn't as responsive as a BeFS query was on my old Pentium 90 with 5200 RPM drives.
At least some part of that is due to the fact that BeOS had a very good scheduler – I remember being impressed one time when I was transferring a lot of video off of a camera building Mozilla from source, and realized that it didn't make either web browsing or email less responsive.
1. this was DV over Firewire so it wasn't a hard-realtime task but the tape made it soft-ish, and the sound change was quite noticeable when the tape drive had to spin down to wait for the host PC, which happened under Windows but never BeOS.
(if you read the section on "Other file systems" it's clear they're picked for being interesting case studies - I imagine FAT is simply not interesting to discuss)
That apparently doesn't seem to matter as it is supported almost everywhere... they've picked some of the most featureful ones, but I think there is much to be said for simplicity and ubiquity since that is what really enables data interchange.
Then again, the fact that it calls BeFS "practical" reminds me of that old joke about maths textbook titles.
> That apparently doesn't seem to matter as it is supported almost everywhere... they've picked some of the most featureful ones, but I think there is much to be said for simplicity and ubiquity since that is what really enables data interchange.
That's true for filesystem choice, but the ubiquity of FAT has nothing to do with "Practical [or impractical] Filesystem Design".
You can't sit down and design a filesystem with "installed everywhere" as a feature; things which are everywhere have already been designed, new designs aren't installed anywhere to begin with.
¹ Which is why FAT is so ubiquitous—it's dead simple.