---
title: "Monitor the Grafana Alloy component controller | Grafana Cloud documentation"
description: "Learn how to monitor controller metrics"
---

# Monitor the Grafana Alloy component controller

The Alloy [component controller](/docs/alloy/latest/get-started/component_controller) exposes Prometheus metrics which you can use to investigate the controller state.

Metrics for the controller are exposed at the `/metrics` HTTP endpoint of the Alloy HTTP server, which defaults to listening on `http://localhost:12345`.

> The documentation for the [`alloy run`](/docs/grafana-cloud/send-data/alloy/reference/cli/run) command describes how to modify the address Alloy listens on for HTTP traffic.

The controller exposes the following metrics:

- `alloy_component_controller_evaluating` (Gauge): Set to `1` whenever the component controller is evaluating components. This value may be misrepresented depending on how fast evaluations complete or how often evaluations occur.
- `alloy_component_controller_running_components` (Gauge): The current number of running components by health. The health is represented in the `health_type` label.
- `alloy_component_evaluation_seconds` (Histogram): The time it takes to evaluate components after one of their dependencies is updated.
- `alloy_component_dependencies_wait_seconds` (Histogram): Time spent by components waiting to be evaluated after one of their dependencies is updated.
- `alloy_component_evaluation_queue_size` (Gauge): The current number of component evaluations waiting to be performed.