`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, CSV, OpenMetrics, etc.)
* `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](https://linux.die.net/man/1/atop)'s design and style decisions.
## Demo
## Installing
### Fedora
`below` is packaged in Fedora as of Fedora 34, and can be installed with:
```shell
sudo dnf install below
```
Optionally, the systemd service for persistent data collection can also be
enabled with:
```shell
sudo systemctl enable --now below
```
### Alpine Linux
`below` is packaged in Alpine Linux - it's available in (upcoming) v3.17+ and
Edge. It can be installed with:
```shell
sudo apk add below
```
Optionally, the OpenRC service for persistent data collection can also be
enabled with:
```shell
sudo rc-service below start
sudo rc-update add below
```
### Gentoo Linux
`below` is available in the
[`sys-process/below`](https://packages.gentoo.org/packages/sys-process/below)
package and can be installed with `emerge`:
```shell
sudo emerge sys-process/below
```
## Installing from source
First, install dependencies listed in [building.md](docs/building.md).
```shell
$ cargo install below
$ below --help
```
For convenience, we also provide a Dockerfile and
[pre-built images](https://hub.docker.com/r/below/below) on Docker Hub.
See [docker.md](docs/docker.md) for how to use them.
## Quickstart
Live view of system:
```shell
$ sudo below live
```
Run recording daemon:
```shell
$ sudo cp ~/.cargo/bin/below /bin/below # if using cargo-install
$ sudo cp etc/below.service /etc/systemd/system
$ sudo systemctl daemon-reload
$ sudo systemctl start below
```
Replay historical data:
```shell
$ below replay -t "3m ago"
```
## Integration with Prometheus/Grafana
`below` has basic support for Prometheus/Grafana through the `dump` interface.
See [contrib/grafana/](contrib/grafana) for more details.
## Comparison with alternative tools
See [comparison.md](docs/comparison.md) for a feature comparison
with alternative tools.
## Contributing
See the [CONTRIBUTING](CONTRIBUTING.md) file for how to help out.
## License
See [LICENSE](LICENSE) file.