Divided proc_cpu_percent by 100 to get value between 0 and 1 (#2812)

CHANGELOG.md

@@ -20,6 +20,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## Fixed
 
+- `opentelemetry-instrumentation-system-metrics` fix `process.runtime.cpu.utilization` values to be shown in range of 0 to 1
+  ([2812](https://github.com/open-telemetry/opentelemetry-python-contrib/pull/2812))
 - `opentelemetry-instrumentation-fastapi` fix `fastapi` auto-instrumentation by removing `fastapi-slim` support, `fastapi-slim` itself is discontinued from maintainers
   ([2783](https://github.com/open-telemetry/opentelemetry-python-contrib/pull/2783))
 - `opentelemetry-instrumentation-aws-lambda` Avoid exception when a handler is not present.

instrumentation/opentelemetry-instrumentation-system-metrics/src/opentelemetry/instrumentation/system_metrics/__init__.py

@@ -729,7 +729,7 @@ class SystemMetricsInstrumentor(BaseInstrumentor):
         """Observer callback for runtime CPU utilization"""
         proc_cpu_percent = self._proc.cpu_percent()
         yield Observation(
-            proc_cpu_percent,
+            proc_cpu_percent / 100,
             self._runtime_cpu_utilization_labels.copy(),
         )
 

instrumentation/opentelemetry-instrumentation-system-metrics/tests/test_system_metrics.py

@@ -839,7 +839,7 @@ class TestSystemMetrics(TestBase):
     def test_runtime_cpu_percent(self, mock_process_cpu_percent):
         mock_process_cpu_percent.configure_mock(**{"return_value": 42})
 
-        expected = [_SystemMetricsResult({}, 42)]
+        expected = [_SystemMetricsResult({}, 0.42)]
         self._test_metrics(
             f"process.runtime.{self.implementation}.cpu.utilization", expected
         )