[hostmetricsreceiver] Set receiver.hostmetrics.normalizeProcessCPUUtilization feature gate as stable (#34764)

**Description:** receiver.hostmetrics.normalizeProcessCPUUtilization
feature gate

**Link to tracking Issue:** #34763

---------

Signed-off-by: Israel Blancas <[email protected]>
Signed-off-by: Israel Blancas <[email protected]>
Co-authored-by: Pablo Baeyens <[email protected]>

Author: Israel Blancas

.chloggen/set-receiver.hostmetrics.normalizeProcessCPUUtilization-to-alpha.yaml

@@ -0,0 +1,27 @@
+# Use this changelog template to create an entry for release notes.
+
+# One of 'breaking', 'deprecation', 'new_component', 'enhancement', 'bug_fix'
+change_type: deprecation
+
+# The name of the component, or a single word describing the area of concern, (e.g. filelogreceiver)
+component: hostmetricsreceiver
+
+# A brief description of the change.  Surround your text with quotes ("") if it needs to start with a backtick (`).
+note: Set the receiver.hostmetrics.normalizeProcessCPUUtilization feature gate to stable.
+
+# Mandatory: One or more tracking issues related to the change. You can use the PR number here if no issue exists.
+issues: [34763]
+
+# (Optional) One or more lines of additional information to render under the primary note.
+# These lines will be padded with 2 spaces and then inserted directly into the document.
+# Use pipe (|) for multiline entries.
+subtext:
+
+# If your change doesn't affect end users or the exported elements of any package,
+# you should instead start your pull request title with [chore] or use the "Skip Changelog" label.
+# Optional: The change log or logs in which this entry should be included.
+# e.g. '[user]' or '[user, api]'
+# Include 'user' if the change is relevant to end users.
+# Include 'api' if there is a change to a library API.
+# Default: '[user]'
+change_logs: []

receiver/hostmetricsreceiver/README.md

@@ -201,19 +201,3 @@ export OTEL_RESOURCE_ATTRIBUTES="service.name=<the name of your service>,service
 ## Entity Events
 
 **Entity Events as logs are experimental** and might eventually be replaced by the result of [the OTEP](https://github.com/open-telemetry/oteps/blob/main/text/entities/0256-entities-data-model.md#entity-events). For now, the hostmetrics receiver can send the host entity event as a log records. By default, the hostmetrics receiver sends periodic EntityState events every 5 minutes. You can change that by setting `metadata_collection_interval`. Entity Events as logs are experimental. The result of the OTEP might eventually replace that.
-
-## Feature Gates
-
-See the [Collector feature gates](https://github.com/open-telemetry/opentelemetry-collector/blob/main/featuregate/README.md#collector-feature-gates) for an overview of feature gates in the collector.
-
-### `receiver.hostmetrics.normalizeProcessCPUUtilization`
-
-When enabled, normalizes the `process.cpu.utilization` metric onto the interval [0-1] by dividing the value by the number of logical processors. With this feature gate disabled, the value of the `process.cpu.utilization` metric may exceed 1.
-
-For example, if you have 4 logical cores on your system, and a process is occupying 2 logical cores for an entire scrape interval, with this feature gate disabled a `process.cpu.utilization` metric will be emitted with a value of 2.  if this feature gate is enabled in the same scenario, the value of the emitted metric will be 0.5.
-
-The schedule for this feature gate is:
-- Introduced in v0.97.0 (March 2024) as `alpha` - disabled by default.
-- Moved to `beta` in v0.100.0 (May 2024) - enabled by default.
-- Moved to `stable` in v0.102.0 (June 2024) - cannot be disabled.
-- Removed three releases after `stable`.

receiver/hostmetricsreceiver/internal/scraper/processscraper/ucal/cpu_utilization_calculator.go

@@ -4,20 +4,24 @@
 package ucal // import "github.com/open-telemetry/opentelemetry-collector-contrib/receiver/hostmetricsreceiver/internal/scraper/processscraper/ucal"
 
 import (
+	"fmt"
 	"time"
 
 	"github.com/shirou/gopsutil/v4/cpu"
 	"go.opentelemetry.io/collector/featuregate"
 	"go.opentelemetry.io/collector/pdata/pcommon"
 )
 
-var normalizeProcessCPUUtilizationFeatureGate = featuregate.GlobalRegistry().MustRegister(
-	"receiver.hostmetrics.normalizeProcessCPUUtilization",
-	featuregate.StageBeta,
-	featuregate.WithRegisterDescription("When enabled, normalizes the process.cpu.utilization metric onto the interval [0-1] by dividing the value by the number of logical processors."),
-	featuregate.WithRegisterFromVersion("v0.97.0"),
-	featuregate.WithRegisterReferenceURL("https://github.com/open-telemetry/opentelemetry-collector-contrib/issues/31368"),
-)
+func init() {
+	_ = featuregate.GlobalRegistry().MustRegister(
+		"receiver.hostmetrics.normalizeProcessCPUUtilization",
+		featuregate.StageStable,
+		featuregate.WithRegisterDescription("When enabled, normalizes the process.cpu.utilization metric onto the interval [0-1] by dividing the value by the number of logical processors."),
+		featuregate.WithRegisterFromVersion("v0.97.0"),
+		featuregate.WithRegisterToVersion("v0.112.0"),
+		featuregate.WithRegisterReferenceURL("https://github.com/open-telemetry/opentelemetry-collector-contrib/issues/31368"),
+	)
+}
 
 // CPUUtilization stores the utilization percents [0-1] for the different cpu states
 type CPUUtilization struct {
@@ -37,6 +41,10 @@ type CPUUtilizationCalculator struct {
 // stored []cpu.TimesStat and time.Time and current []cpu.TimesStat and current time.Time
 // If no previous data is stored it will return empty slice of CPUUtilization and no error
 func (c *CPUUtilizationCalculator) CalculateAndRecord(now pcommon.Timestamp, logicalCores int, currentCPUStats *cpu.TimesStat, recorder func(pcommon.Timestamp, CPUUtilization)) error {
+	if logicalCores < 1 {
+		return fmt.Errorf("number of logical cores is %d", logicalCores)
+	}
+
 	if c.previousCPUStats != nil {
 		recorder(now, cpuUtilization(logicalCores, c.previousCPUStats, c.previousReadTime, currentCPUStats, now))
 	}
@@ -57,12 +65,9 @@ func cpuUtilization(logicalCores int, startStats *cpu.TimesStat, startTime pcomm
 	systemUtilization := (endStats.System - startStats.System) / elapsedTime
 	ioWaitUtilization := (endStats.Iowait - startStats.Iowait) / elapsedTime
 
-	if normalizeProcessCPUUtilizationFeatureGate.IsEnabled() && logicalCores > 0 {
-		// Normalize onto the [0-1] interval by dividing by the number of logical cores
-		userUtilization /= float64(logicalCores)
-		systemUtilization /= float64(logicalCores)
-		ioWaitUtilization /= float64(logicalCores)
-	}
+	userUtilization /= float64(logicalCores)
+	systemUtilization /= float64(logicalCores)
+	ioWaitUtilization /= float64(logicalCores)
 
 	return CPUUtilization{
 		User:   userUtilization,

receiver/hostmetricsreceiver/internal/scraper/processscraper/ucal/cpu_utilization_calculator_test.go

@@ -9,8 +9,6 @@ import (
 
 	"github.com/shirou/gopsutil/v4/cpu"
 	"github.com/stretchr/testify/assert"
-	"github.com/stretchr/testify/require"
-	"go.opentelemetry.io/collector/featuregate"
 	"go.opentelemetry.io/collector/pdata/pcommon"
 )
 
@@ -32,7 +30,7 @@ func TestCpuUtilizationCalculator_Calculate(t *testing.T) {
 		previousReadTime    pcommon.Timestamp
 		previousCPUStat     *cpu.TimesStat
 		expectedUtilization *CPUUtilization
-		normalize           bool
+		shouldError         bool
 	}{
 		{
 			name:         "no previous times",
@@ -96,28 +94,6 @@ func TestCpuUtilizationCalculator_Calculate(t *testing.T) {
 				System: 0.15,
 				Iowait: 0.0005,
 			},
-			normalize: true,
-		},
-		{
-			name:             "one second time delta, 2 logical cores, not normalized",
-			logicalCores:     2,
-			previousReadTime: 1640097430772858000,
-			currentReadTime:  1640097431772858000,
-			previousCPUStat: &cpu.TimesStat{
-				User:   8258.4,
-				System: 6193.3,
-				Iowait: 34.201,
-			},
-			currentCPUStat: &cpu.TimesStat{
-				User:   8258.5,
-				System: 6193.6,
-				Iowait: 34.202,
-			},
-			expectedUtilization: &CPUUtilization{
-				User:   0.1,
-				System: 0.3,
-				Iowait: 0.001,
-			},
 		},
 		{
 			name:             "0 logical cores",
@@ -134,27 +110,27 @@ func TestCpuUtilizationCalculator_Calculate(t *testing.T) {
 				System: 6193.6,
 				Iowait: 34.202,
 			},
-			expectedUtilization: &CPUUtilization{
-				User:   0.1,
-				System: 0.3,
-				Iowait: 0.001,
-			},
+			shouldError: true,
 		},
 	}
 	for _, test := range testCases {
 		test := test
 		t.Run(test.name, func(t *testing.T) {
-			setNormalizeProcessCPUUtilizationFeatureGate(t, test.normalize)
 			recorder := inMemoryRecorder{}
 			calculator := CPUUtilizationCalculator{
 				previousReadTime: test.previousReadTime,
 				previousCPUStats: test.previousCPUStat,
 			}
 			err := calculator.CalculateAndRecord(test.currentReadTime, test.logicalCores, test.currentCPUStat, recorder.record)
-			assert.NoError(t, err)
-			assert.InDelta(t, test.expectedUtilization.System, recorder.cpuUtilization.System, 0.00001)
-			assert.InDelta(t, test.expectedUtilization.User, recorder.cpuUtilization.User, 0.00001)
-			assert.InDelta(t, test.expectedUtilization.Iowait, recorder.cpuUtilization.Iowait, 0.00001)
+			if test.shouldError {
+				assert.Error(t, err)
+			} else {
+				assert.NoError(t, err)
+				assert.InDelta(t, test.expectedUtilization.System, recorder.cpuUtilization.System, 0.00001)
+				assert.InDelta(t, test.expectedUtilization.User, recorder.cpuUtilization.User, 0.00001)
+				assert.InDelta(t, test.expectedUtilization.Iowait, recorder.cpuUtilization.Iowait, 0.00001)
+			}
+
 		})
 	}
 }
@@ -185,20 +161,3 @@ func Test_cpuUtilization(t *testing.T) {
 	assert.InDelta(t, expectedUtilization.Iowait, actualUtilization.Iowait, 0.00001)
 
 }
-
-func setNormalizeProcessCPUUtilizationFeatureGate(t *testing.T, val bool) {
-	wasEnabled := normalizeProcessCPUUtilizationFeatureGate.IsEnabled()
-	err := featuregate.GlobalRegistry().Set(
-		normalizeProcessCPUUtilizationFeatureGate.ID(),
-		val,
-	)
-	require.NoError(t, err)
-
-	t.Cleanup(func() {
-		err := featuregate.GlobalRegistry().Set(
-			normalizeProcessCPUUtilizationFeatureGate.ID(),
-			wasEnabled,
-		)
-		require.NoError(t, err)
-	})
-}