From 26f499279fd396d08d7d8cbfae22fe97ca754c26 Mon Sep 17 00:00:00 2001
From: Chris Mark <chrismarkou92@gmail.com>
Date: Thu, 26 Oct 2023 11:45:24 +0100
Subject: [PATCH] Add `system.cpu.frequency` metric. (#337)

Signed-off-by: ChrsMark <chrismarkou92@gmail.com>
Co-authored-by: Pablo Baeyens <pablo.baeyens@datadoghq.com>
---
 CHANGELOG.md                      |  2 ++
 docs/system/system-metrics.md     | 17 +++++++++++++++++
 model/metrics/system-metrics.yaml |  9 +++++++++
 3 files changed, 28 insertions(+)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index e1382e9c0d..a7e7f656d5 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -182,6 +182,8 @@ release.
 - BREAKING: Rename `telemetry.auto.version` resource attribute to `telemetry.distro.version`
   and add `telemetry.distro.name` resource attribute
   ([#178](https://github.com/open-telemetry/semantic-conventions/pull/178))
+- Add `system.cpu.frequency` metric.
+  ([#337](https://github.com/open-telemetry/semantic-conventions/pull/337))
 - Improve HTTP metric briefs.
   ([#366](https://github.com/open-telemetry/semantic-conventions/pull/366))
 - Add `host.ip` resource attribute convention.
diff --git a/docs/system/system-metrics.md b/docs/system/system-metrics.md
index 14254bf534..c7bdd1703f 100644
--- a/docs/system/system-metrics.md
+++ b/docs/system/system-metrics.md
@@ -26,6 +26,7 @@ Resource attributes related to a host, SHOULD be reported under the `host.*` nam
   * [Metric: `system.cpu.utilization`](#metric-systemcpuutilization)
   * [Metric: `system.cpu.physical.count`](#metric-systemcpuphysicalcount)
   * [Metric: `system.cpu.logical.count`](#metric-systemcpulogicalcount)
+  * [Metric: `system.cpu.frequency`](#metric-systemcpufrequency)
 - [Memory Metrics](#memory-metrics)
   * [Metric: `system.memory.usage`](#metric-systemmemoryusage)
   * [Metric: `system.memory.utilization`](#metric-systemmemoryutilization)
@@ -145,6 +146,22 @@ This metric is [recommended][MetricRecommended].
 <!-- semconv metric.system.cpu.logical.count(full) -->
 <!-- endsemconv -->
 
+### Metric: `system.cpu.frequency`
+
+This metric is [recommended][MetricRecommended].
+
+<!-- semconv metric.system.cpu.frequency(metric_table) -->
+| Name     | Instrument Type | Unit (UCUM) | Description    |
+| -------- | --------------- | ----------- | -------------- |
+| `system.cpu.frequency` | Gauge | `{Hz}` | Reports the current frequency of the CPU in Hz |
+<!-- endsemconv -->
+
+<!-- semconv metric.system.cpu.frequency(full) -->
+| Attribute  | Type | Description  | Examples  | Requirement Level |
+|---|---|---|---|---|
+| `system.cpu.logical_number` | int | The logical CPU number [0..n-1] | `1` | Recommended |
+<!-- endsemconv -->
+
 ## Memory Metrics
 
 **Description:** System level memory metrics capture under the namespace `system.memory`.
diff --git a/model/metrics/system-metrics.yaml b/model/metrics/system-metrics.yaml
index eb69d3f992..9f582e4b19 100644
--- a/model/metrics/system-metrics.yaml
+++ b/model/metrics/system-metrics.yaml
@@ -61,6 +61,15 @@ groups:
       - ref: system.cpu.state
       - ref: system.cpu.logical_number
 
+  - id: metric.system.cpu.frequency
+    type: metric
+    metric_name: system.cpu.frequency
+    brief: "Reports the current frequency of the CPU in Hz"
+    instrument: gauge
+    unit: "{Hz}"
+    attributes:
+      - ref: system.cpu.logical_number
+
   - id: metric.system.cpu.physical.count
     type: metric
     metric_name: system.cpu.physical.count