> ## Documentation Index
> Fetch the complete documentation index at: https://docs.appsignal.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Garbage Collection

export const VersionRequirements = ({versions = []}) => {
  if (!Array.isArray(versions) || versions.length === 0) {
    return null;
  }
  const boundaries = {
    upper: " or lower",
    exact: "",
    lower: " or higher"
  };
  const containerStyle = {
    marginTop: "0.5rem",
    marginBottom: "1.5rem"
  };
  const lineStyle = {
    display: "block",
    margin: "0 0 0.35rem 0",
    fontSize: "0.875rem",
    lineHeight: "1.4"
  };
  const pillBaseStyle = {
    display: "inline-block",
    padding: "0.1em 0.4em",
    borderRadius: "0.25rem",
    border: "1px solid",
    fontFamily: "ui-monospace, SFMono-Regular, Menlo, monospace",
    fontSize: "0.85em",
    fontWeight: 500
  };
  const pillColors = {
    "AppSignal for Elixir": {
      background: "#f3e8ff",
      borderColor: "#e9d5ff",
      color: "#9333ea"
    },
    "AppSignal for Front-end": {
      background: "#fef9c3",
      borderColor: "#fde68a",
      color: "#ca8a04"
    },
    "AppSignal for Go": {
      background: "#ccfbf1",
      borderColor: "#99f6e4",
      color: "#0d9488"
    },
    "AppSignal for JavaScript": {
      background: "#fef9c3",
      borderColor: "#fde68a",
      color: "#ca8a04"
    },
    "AppSignal for Node.js": {
      background: "#dcfce7",
      borderColor: "#bbf7d0",
      color: "#16a34a"
    },
    "AppSignal for Python": {
      background: "#dbeafe",
      borderColor: "#bfdbfe",
      color: "#2563eb"
    },
    "AppSignal for Ruby": {
      background: "#fee2e2",
      borderColor: "#fecaca",
      color: "#dc2626"
    },
    "AppSignal for Rust": {
      background: "#ffedd5",
      borderColor: "#fed7aa",
      color: "#ea580c"
    }
  };
  const defaultPillColor = {
    background: "#f4f4f5",
    borderColor: "#e4e4e7",
    color: "#52525b"
  };
  const getPillStyle = name => ({
    ...pillBaseStyle,
    ...pillColors[name] || defaultPillColor
  });
  const getBoundText = bound => {
    return boundaries[bound] || boundaries.lower;
  };
  return <div style={containerStyle}>
      {versions.map((v, i) => <p key={`${v.name}-${v.version}-${v.bound || "lower"}-${i}`} style={lineStyle}>
          This feature requires{" "}
          <code style={getPillStyle(v.name)}>{v.name}</code> version {v.version}
          {getBoundText(v.bound)}.
        </p>)}
    </div>;
};

<VersionRequirements
  versions={[
{ name: "AppSignal for Ruby", version: "3.1.4" }
]}
/>

The Ruby VM (Virtual Machine) uses Garbage Collection (GC) to prevent it from running out of process memory. Garbage Collection helps prevent your application from suffering memory outages due to running out of memory.

This processes of cleaning up unused memory in Ruby apps can happen at any time. To get more insights into this you can use [Ruby's Garbage Collection profiler](https://ruby-doc.org/core/GC/Profiler.html).

## Profiler

<Warning>
  We do not recommend enabling the Garbage Collection profiler in production
  environments, at least not for extended periods of time. The profiler's
  additional overhead may negatively impact your application's performance.
</Warning>

When the Ruby Garbage Collection profiler is enabled AppSignal will automatically collect metrics for its Ruby VM magic dashboard. The "GC time" graph will show how long the Ruby VM took to clean up the unused memory between measurements. This graph will spike if it suddenly has to process a lot more memory, such as after a high memory usage task or request for example. The GC profiler is disabled by default, so no metrics are reported in this graph.

To enable the GC profiler, add the code shown below to your application. The profiler can be enabled at any time in the application, such as on boot or in preparation of memory intensive operations.

Once the GC profiler is enabled, the "GC time" graph will start showing metrics after at least two minutes. This metric is reported by our [minutely probes](/ruby/instrumentation/minutely-probes) system and new measurements are made every minute.

<CodeGroup>
  ```ruby Ruby theme={null}
  GC::Profiler.enable
  ```
</CodeGroup>

To temporarily enable the GC profiler, make sure to disable the profiler afterwards.

<CodeGroup>
  ```ruby Ruby theme={null}
  GC::Profiler.enable

  # Do memory intensive operation

  GC::Profiler.disable
  ```
</CodeGroup>

For the Ruby gem to report any duration over zero for the garbage collection time, the profiler must be enabled for more than two minutes. This is the initial time the Ruby gem needs to measure the garbage collection time. We recommend enabling GC profiling for longer than the minimum of two minutes to ensure we have complete measurements required to compare and graph.