[toast0]

All of those things come with tradeoffs.

Compression tradesoff compute vs i/o, if your system has weak compute, it's a bad deal. Most modern systems should do well with compression.

Dedupe needs indexing to find duplicates and makes writes complex (at least for realtime dedupe). I think online dedupe has pretty limited application, but offline dedupe is interesting.

Copy on write again makes writes complex, and tends to fragmentation of files that are modified. Free snapshots are only free when copy on write is the norm (otherwise, you have to copy on write while a snapshot is open, as on FreeBSD UFS). Copy on write offers a lot, but some applications would suffer.

Dynamic resizing (upwards) is pretty common now. Resize down less so. Zfs downsizing is available, but at least when I tried it, the filesystem became unbootable, so maybe not super useful IMHO.

Logical partitions, per user stuff, qos adds complexity probably not needed for everyone.

[Dylan16807]

> Compression tradesoff compute vs i/o, if your system has weak compute, it's a bad deal. Most modern systems should do well with compression.

Older systems with worse compute also had worse i/o. There are cases where fast compression slows things down, but they're rare enough to make compression the better default.

[1718627440]

I certainly don't want my compiler to get slower, because we now compress the files that are gone in a few minutes anyway. Compression is useful for archiving files, but for anything that you currently work with, it's useless and only wastes compute.

[Dylan16807]

If you're limited by your SSD, one core running lz4 (or zstd) will double your write speed for object files. If you're not writing hundreds of megabytes per second, then you'll barely notice the overhead at that phase while it makes later phases that load the data back snappier.

If everything fits in ram then compression could be postponed.

And for that area in between, where your files don't fit in ram but compressed they would fit in ram, compression can give you a big speed boost.

[1718627440]

That's true. I think less memory is often accompanied with less compute. For example "one core running" is 50% of my available compute.