zftop

Terminal dashboard for ZFS. Like htop, but for your pools.

Instead of juggling zpool status, arc_summary, zfs list, and smartctl, zftop puts it all on one screen.

Install

curl -fsSL https://git.skylantix.com/rbitton/zftop/-/raw/main/install.sh | sh

Or grab a binary from the releases page, or:

yay -S zftop          # AUR
cargo install zftop   # crates.io (needs rustc 1.85+)

Already have it? zftop --upgrade will print the update command.

What it shows

Four tabs, refreshing once a second:

• Overview — RAM bar, ARC gauge + hit ratios, pool health/capacity at a glance.
• Pools — expandable tree of pools and their vdevs. ←/→ collapse/expand each pool. Pool rows show health, capacity, frag, scrub state, errors. Vdev rows show state, kind, size, device path, and per-vdev R/W/C error counts. Enter drills into a per-pool detail page (scrub progress, future SMART rollup).
• Datasets — tree view of every imported pool's filesystems and zvols. ←/→ collapse/expand. Rows show used / referenced / available / compression ratio. Enter drills into per-dataset properties (mountpoint, recordsize, quota usage, dedup, encryption, etc.).
• ARC — size gauge, MFU/MRU/metadata breakdown, hit ratios, compression ratio, throughput.

Data comes from /proc/spl/kstat/zfs/arcstats + /proc/meminfo on Linux, sysctl on FreeBSD. Pool data is read through libzfs directly without parsing zpool.

Usage

zftop                    # default: 1s refresh
zftop -n 500             # 500ms
zftop --help             # all options

Controls

Requirements

• Linux with OpenZFS loaded, or FreeBSD 14+
• libzfs at runtime (comes with ZFS)
• Prebuilt binaries need glibc 2.28+ (Debian 10, Ubuntu 18.04, RHEL 8, Arch, etc). Older or musl systems: use cargo install zftop
• A Unicode-capable terminal for the dataset tree glyphs (▼/▶). Standard terminal emulators all qualify; bare Linux text consoles (tty1) may render the glyphs as ?.

How the RAM bar works

The RAM bar shows what's currently held, not what's reclaimable. This is intentional, and it'll look fuller than htop's bar.

Linux: User+Kernel | ARC (size + overhead_size) | Buf/Cache | Free (MemFree, not MemAvailable)

FreeBSD: Wired | ARC | Active | Inactive+Laundry

The "ZFS available" label on the right side is arcstats.memory_available_bytes: ZFS's own reclaim estimate, so you can reconcile with htop.

Building from source

git clone https://git.skylantix.com/rbitton/zftop.git
cd zftop
cargo build --release
sudo install -Dm755 target/release/zftop /usr/bin/zftop

FreeBSD: same thing, install to /usr/local/bin instead. The --source and --meminfo flags are Linux-only and ignored on FreeBSD.

Roadmap

zftop is a finishable project (or at least everything up until fleet mode, which will likely take a lot of ongoing work).

• v0.1 ARC dashboard ✓
• v0.2 Pools: capacity, health, vdev trees, scrub status ✓
• v0.3 Datasets: tree view, properties, quota usage ✓
• v0.3.1 Pools: tree view, vdev expand/collapse, device paths, R/W/C breakdown ✓
• v0.4 Snapshots, with Sanoid retention awareness
• v0.5 SMART health joined to vdev members
• v1.0 Remote/fleet mode over SSH

License

GPLv3+. See LICENSE.