below is an interactive tool to view and record historical system data.
The name “below” stems from the fact that the below developers rejected many of atop’s design and style decisions.
This is free and open source software.
Key Features
- Terminal interface:
- Supports filtering, zooming, pausing, sorting, and scrolling.
- Built in support for persisting/replaying historical data.
- In-depth host-level stats.
- cgroup awareness with cgroup tree view.
below dumpfor scriptable access to historical data.- Goes to great lengths to avoid priority inversions during host resource contention.
- Supports:
- Information regarding hardware resource utilization.
- Viewing the cgroup hierarchy.
- cgroup and process information.
- Pressure stall information (PSI).
- Record mode to record system data.
- Replay mode to replay historical system data.
- Live mode to view live system data.
- Dump subcommand to report script-friendly information (eg JSON, CSV, OpenMetrics, etc.).
- Snapshot subcommand to create a replayable snapshot file of historical system data.
- Basic support for Prometheus/Grafana through the dump interface.
Website: github.com/facebookincubator/below
Support:
Developer: Meta Incubator
License: Apache License 2.0

below is written in Rust. Learn Rust with our recommended free books and free tutorials
Related Software
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|---|---|
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Read our verdict in the software roundup.
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