Control Group V2 exporter

This is a lightweight Prometheus exporter for cgroups that only supports the unified cgroup v2 hierarchy. It exposes usage metrics for each cgroup in the hierarchy.

Metrics supported are:

• Pressure stall information (io.pressure, memory.pressure, cpu.pressure). Useful as a leading indicator for performance issues.
• Events (like OOM, hitting max CPU, Memory, IO, etc) (io.events, memory.events)
• Resource usage (memory.usage, cpu.usage) and limits (io.max, memory.{min,low,high,max}, cpu.{min,low,high,max})
• Detailed resource usage (io.stat, memory.stat, cpu.stat)
  • io.stat gives IOPS and bytes read/written per device
  • memory.stat gives page faults, cache, swap, etc
  • cpu.stat gives number of times the CPU was throttled, time spent in different states, etc

Systemd dropped support for the legacy cgroup hierarchy in version 256. So there is no point in having the complexity of supporting both cgroup versions.

Why another exporter?

Cgroup exposes a lot of metrics. This can quickly become overwhelming. Non of the other solutions allow you to enable and disable certain metrics to be collected throughout the hierarchy. Neither does this exporter, but we have an issue open for it: #1

google/cadvisor is too heavy-weight, tries to do way more than cgroups, tries to support both cgroupv1 and cgroupv2, and is missing a lot of metrics (like pressure stall information). Furthermore they focus on "containers", whilst cgroups and containers are not synonyms. Cgroups are used for all services on a modern linux system for resource management; not just containers.

mosquito/cgroups-exporter also comes with the baggage of supporting both cgroupv1 and cgroupv2, and is missing a lot of metrics.

treydock/cgroup_exporter also comes with the baggage of supporting both cgroupv1 and cgroupv2, and is missing a lot of metrics.