below is an interactive tool to view and record historical system data. It has support for:

• 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 and CSV)
• snapshot subcommand to create a replayable snapshot file of historical system data

below does not have support for cgroup1.

The name "below" stems from the fact that the below developers rejected many of atop's design and style decisions.

below is packaged in Fedora as of Fedora 34, and can be installed with:

sudo dnf install below

Optionally, the systemd service for persistent data collection can also be enabled with:

sudo systemctl enable --now below

below is packaged in Alpine Linux - it's available in (upcoming) v3.17+ and Edge. It can be installed with:

sudo apk add below

Optionally, the OpenRC service for persistent data collection can also be enabled with:

sudo rc-service below start
sudo rc-update add below

below is available in the sys-process/below package and can be installed with emerge:

sudo emerge sys-process/below

First, install dependencies listed in building.md.

$ cargo install below
$ below --help

For convenience, we also provide a Dockerfile and pre-built images on Docker Hub. See docker.md for how to use them.

Live view of system:

$ sudo below live

Run recording daemon:

$ sudo cp ~/.cargo/bin/below /bin/below  # if using cargo-install
$ sudo cp resctl/below/etc/below.service /etc/systemd/system
$ sudo systemctl daemon-reload
$ sudo systemctl start below

Replay historical data:

$ below replay -t "3m ago"

See comparison.md for a feature comparison with alternative tools.

See the CONTRIBUTING file for how to help out.

See LICENSE file.