[receiver/hostmetrics] Deprecate processesscraper

.chloggen/system_processes_metrics_to_process_scraper.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: enhancement
+
+# 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: Adds the system.processes.* metrics to the process scraper. Also adds a deprecation warning to the processesscraper.
+
+# Mandatory: One or more tracking issues related to the change. You can use the PR number here if no issue exists.
+issues: [30895]
+
+# (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

@@ -47,8 +47,8 @@ The available scrapers are:
 | [memory]     | All                          | Memory utilization metrics                             |
 | [network]    | All                          | Network interface I/O metrics & TCP connection metrics |
 | [paging]     | All                          | Paging/Swap space utilization and I/O metrics          |
-| [processes]  | Linux, Mac                   | Process count metrics                                  |
-| [process]    | Linux, Windows, Mac          | Per process CPU, Memory, and Disk I/O metrics          |
+| [processes]  | Linux, Mac                   | DEPRECATED: Use `process` scraper                      |
+| [process]    | Linux, Windows, Mac          | Per process CPU, Memory, and Disk I/O metrics, full system process counts |
 
 [cpu]: ./internal/scraper/cpuscraper/documentation.md
 [disk]: ./internal/scraper/diskscraper/documentation.md
@@ -160,14 +160,14 @@ service:
 
 Host metrics are collected from the Linux system directories on the filesystem.
 You likely want to collect metrics about the host system and not the container.
-This is achievable by following these steps: 
+This is achievable by following these steps:
 
 #### 1. Bind mount the host filesystem
 
-The simplest configuration is to mount the entire host filesystem when running 
+The simplest configuration is to mount the entire host filesystem when running
 the container. e.g. `docker run -v /:/hostfs ...`.
 
-You can also choose which parts of the host filesystem to mount, if you know 
+You can also choose which parts of the host filesystem to mount, if you know
 exactly what you'll need. e.g. `docker run -v /proc:/hostfs/proc`.
 
 #### 2. Configure `root_path`
@@ -191,3 +191,18 @@ Currently, the hostmetrics receiver does not set any Resource attributes on the
 export OTEL_RESOURCE_ATTRIBUTES="service.name=<the name of your service>,service.namespace=<the namespace of your service>,service.instance.id=<uuid of the instance>"
 ```
 
+## Processes scraper deprecation
+
+The `processes` scraper has been deprecated in favor of the `process` scraper. The `processes` scraper will be removed in a future release. To enable the same functionality, remove the `processes` scraper and enable the `system.processes.*` metrics in the `process` scraper:
+
+```yaml
+receivers:
+  hostmetrics:
+    scrapers:
+      process:
+        metrics:
+          system.processes.created:
+            enabled: true
+          system.processes.count:
+            enabled: true
+```

receiver/hostmetricsreceiver/hostmetrics_receiver_test.go

@@ -210,6 +210,92 @@ func appendMapInto(m1 map[string]struct{}, m2 map[string]struct{}) {
 	}
 }
 
+func Test_ProcessesScraperDeprecationCompatibility(t *testing.T) {
+	if runtime.GOOS != "linux" {
+		t.Skip("Skipping test on non-Linux platform")
+	}
+	processesConfig := &Config{
+		ScraperControllerSettings: scraperhelper.ScraperControllerSettings{
+			CollectionInterval: 100 * time.Millisecond,
+		},
+		Scrapers: map[string]internal.Config{
+			processscraper.TypeStr:   scraperFactories[processscraper.TypeStr].CreateDefaultConfig(),
+			processesscraper.TypeStr: scraperFactories[processesscraper.TypeStr].CreateDefaultConfig(),
+		},
+	}
+	processConfig := &Config{
+		ScraperControllerSettings: scraperhelper.ScraperControllerSettings{
+			CollectionInterval: 100 * time.Millisecond,
+		},
+		Scrapers: map[string]internal.Config{
+			processscraper.TypeStr: (&processscraper.Factory{}).CreateDefaultConfigWithSystemProcessesEnabled(),
+		},
+	}
+
+	processesSink := runScrapeForConfig(t, processesConfig)
+	processSink := runScrapeForConfig(t, processConfig)
+	assertProcessMetricShape(t, processesSink)
+	assertProcessMetricShape(t, processSink)
+}
+
+func runScrapeForConfig(t *testing.T, cfg *Config) *consumertest.MetricsSink {
+	t.Helper()
+
+	scraperFactories = factories
+	sink := new(consumertest.MetricsSink)
+
+	receiver, err := NewFactory().CreateMetricsReceiver(context.Background(), creationSet, cfg, sink)
+	require.NoError(t, err, "Failed to create metrics receiver: %v", err)
+
+	ctx, cancelFn := context.WithCancel(context.Background())
+	err = receiver.Start(ctx, componenttest.NewNopHost())
+	require.NoError(t, err, "Failed to start metrics receiver: %v", err)
+	defer func() { assert.NoError(t, receiver.Shutdown(context.Background())) }()
+
+	// canceling the context provided to Start should not cancel any async processes initiated by the receiver
+	cancelFn()
+
+	const tick = 50 * time.Millisecond
+	const waitFor = 10 * time.Second
+	require.Eventuallyf(t, func() bool {
+		return len(sink.AllMetrics()) > 0
+	}, waitFor, tick, "No metrics were collected after %v", waitFor)
+
+	return sink
+}
+
+func assertProcessMetricShape(t *testing.T, sink *consumertest.MetricsSink) {
+	// Whether the metrics came from using the deprecated scraper or just the process scraper
+	// with the system.processes.* metrics enabled, the result should be the same.
+	// There will be process resources at the beginning, and at the end should be an empty
+	// resource with the `system.processes.*` metrics present.
+
+	metrics := sink.AllMetrics()[0]
+
+	// Check that all resources up until the final one are process resources.
+	for i := 0; i < metrics.ResourceMetrics().Len()-1; i++ {
+		_, ok := metrics.ResourceMetrics().At(i).Resource().Attributes().Get("process.pid")
+		assert.True(t, ok)
+	}
+
+	// Check that the final resource has the system.processes.* metrics.
+	finalResourceMetrics := metrics.ResourceMetrics().At(metrics.ResourceMetrics().Len() - 1).ScopeMetrics().At(0).Metrics()
+	found := map[string]bool{
+		"system.processes.count":   false,
+		"system.processes.created": false,
+	}
+	for i := 0; i < finalResourceMetrics.Len(); i++ {
+		metric := finalResourceMetrics.At(i)
+		if metric.Name() == "system.processes.count" {
+			found["system.processes.count"] = true
+		} else if metric.Name() == "system.processes.created" {
+			found["system.processes.created"] = true
+		}
+	}
+	assert.True(t, found["system.processes.count"])
+	assert.True(t, found["system.processes.created"])
+}
+
 const mockTypeStr = "mock"
 
 type mockConfig struct{}
@@ -404,7 +490,7 @@ func Benchmark_ScrapeSystemMetrics(b *testing.B) {
 }
 
 func Benchmark_ScrapeSystemAndProcessMetrics(b *testing.B) {
-	if runtime.GOOS != "linux" && runtime.GOOS != "windows" {
+	if runtime.GOOS != "linux" {
 		b.Skip("skipping test on non linux/windows")
 	}
 
@@ -424,3 +510,34 @@ func Benchmark_ScrapeSystemAndProcessMetrics(b *testing.B) {
 
 	benchmarkScrapeMetrics(b, cfg)
 }
+
+func Benchmark_ScrapeProcessMetricsWithSystemProcessMetrics(b *testing.B) {
+	if runtime.GOOS != "linux" {
+		b.Skip("skipping test on non linux")
+	}
+
+	cfg := &Config{
+		ScraperControllerSettings: scraperhelper.NewDefaultScraperControllerSettings(""),
+		Scrapers: map[string]internal.Config{
+			processscraper.TypeStr: (&processscraper.Factory{}).CreateDefaultConfigWithSystemProcessesEnabled(),
+		},
+	}
+
+	benchmarkScrapeMetrics(b, cfg)
+}
+
+func Benchmark_ScrapeProcessMetricsWithDeprecatedProcessesScraper(b *testing.B) {
+	if runtime.GOOS != "linux" {
+		b.Skip("skipping test on non linux")
+	}
+
+	cfg := &Config{
+		ScraperControllerSettings: scraperhelper.NewDefaultScraperControllerSettings(""),
+		Scrapers: map[string]internal.Config{
+			processscraper.TypeStr:   (&processscraper.Factory{}).CreateDefaultConfig(),
+			processesscraper.TypeStr: (&processesscraper.Factory{}).CreateDefaultConfig(),
+		},
+	}
+
+	benchmarkScrapeMetrics(b, cfg)
+}

receiver/hostmetricsreceiver/internal/scraper/processesscraper/factory.go

@@ -37,12 +37,23 @@ func (f *Factory) CreateMetricsScraper(
 	settings receiver.CreateSettings,
 	config internal.Config,
 ) (scraperhelper.Scraper, error) {
+	settings.Logger.Warn(`processes scraping will soon be deprecated, system.processes.created and system.processes.count metrics have been moved to the process scraper.
+	To enable them, apply the following config:
+
+	scrapers:
+	  process:
+	    metrics:
+	      system.processes.created:
+	        enabled: true
+	      system.processes.count:
+	        enabled: true
+`)
 	cfg := config.(*Config)
-	s := newProcessesScraper(ctx, settings, cfg)
+	s := NewProcessesScraper(ctx, settings, cfg)
 
 	return scraperhelper.NewScraper(
 		TypeStr,
-		s.scrape,
-		scraperhelper.WithStart(s.start),
+		s.Scrape,
+		scraperhelper.WithStart(s.Start),
 	)
 }

receiver/hostmetricsreceiver/internal/scraper/processesscraper/processes_scraper.go

@@ -31,20 +31,20 @@ var metricsLength = func() int {
 	return n
 }()
 
-// scraper for Processes Metrics
-type scraper struct {
+// Scraper for Processes Metrics
+type Scraper struct {
 	settings receiver.CreateSettings
 	config   *Config
 	mb       *metadata.MetricsBuilder
 
 	// for mocking gopsutil
-	getMiscStats func(context.Context) (*load.MiscStat, error)
-	getProcesses func() ([]proc, error)
+	GetMiscStats func(context.Context) (*load.MiscStat, error)
+	GetProcesses func() ([]Proc, error)
 	bootTime     func(context.Context) (uint64, error)
 }
 
 // for mocking out gopsutil process.Process
-type proc interface {
+type Proc interface {
 	Status() ([]string, error)
 }
 
@@ -53,16 +53,16 @@ type processesMetadata struct {
 	processesCreated *int64                             // ignored if enableProcessesCreated is false
 }
 
-// newProcessesScraper creates a set of Processes related metrics
-func newProcessesScraper(_ context.Context, settings receiver.CreateSettings, cfg *Config) *scraper {
-	return &scraper{
+// NewProcessesScraper creates a set of Processes related metrics
+func NewProcessesScraper(_ context.Context, settings receiver.CreateSettings, cfg *Config) *Scraper {
+	return &Scraper{
 		settings:     settings,
 		config:       cfg,
-		getMiscStats: load.MiscWithContext,
-		getProcesses: func() ([]proc, error) {
+		GetMiscStats: load.MiscWithContext,
+		GetProcesses: func() ([]Proc, error) {
 			ctx := context.WithValue(context.Background(), common.EnvKey, cfg.EnvMap)
 			ps, err := process.ProcessesWithContext(ctx)
-			ret := make([]proc, len(ps))
+			ret := make([]Proc, len(ps))
 			for i := range ps {
 				ret[i] = ps[i]
 			}
@@ -72,7 +72,7 @@ func newProcessesScraper(_ context.Context, settings receiver.CreateSettings, cf
 	}
 }
 
-func (s *scraper) start(ctx context.Context, _ component.Host) error {
+func (s *Scraper) Start(ctx context.Context, _ component.Host) error {
 	ctx = context.WithValue(ctx, common.EnvKey, s.config.EnvMap)
 	bootTime, err := s.bootTime(ctx)
 	if err != nil {
@@ -83,7 +83,7 @@ func (s *scraper) start(ctx context.Context, _ component.Host) error {
 	return nil
 }
 
-func (s *scraper) scrape(_ context.Context) (pmetric.Metrics, error) {
+func (s *Scraper) Scrape(_ context.Context) (pmetric.Metrics, error) {
 	now := pcommon.NewTimestampFromTime(time.Now())
 
 	md := pmetric.NewMetrics()

receiver/hostmetricsreceiver/internal/scraper/processesscraper/processes_scraper_test.go

@@ -33,7 +33,7 @@ func TestScrape(t *testing.T) {
 	type testCase struct {
 		name         string
 		getMiscStats func(context.Context) (*load.MiscStat, error)
-		getProcesses func() ([]proc, error)
+		getProcesses func() ([]Proc, error)
 		expectedErr  string
 		validate     func(*testing.T, pmetric.MetricSlice)
 	}
@@ -44,41 +44,41 @@ func TestScrape(t *testing.T) {
 	}, {
 		name:         "FakeData",
 		getMiscStats: func(ctx context.Context) (*load.MiscStat, error) { return &fakeData, nil },
-		getProcesses: func() ([]proc, error) { return fakeProcessesData, nil },
+		getProcesses: func() ([]Proc, error) { return fakeProcessesData, nil },
 		validate:     validateFakeData,
 	}, {
 		name:         "ErrorFromMiscStat",
 		getMiscStats: func(context.Context) (*load.MiscStat, error) { return &load.MiscStat{}, errors.New("err1") },
 		expectedErr:  "err1",
 	}, {
 		name:         "ErrorFromProcesses",
-		getProcesses: func() ([]proc, error) { return nil, errors.New("err2") },
+		getProcesses: func() ([]Proc, error) { return nil, errors.New("err2") },
 		expectedErr:  "err2",
 	}, {
 		name:         "ErrorFromProcessShouldBeIgnored",
-		getProcesses: func() ([]proc, error) { return []proc{errProcess{}}, nil },
+		getProcesses: func() ([]Proc, error) { return []Proc{errProcess{}}, nil },
 	}, {
 		name:     "Validate Start Time",
 		validate: validateStartTime,
 	}}
 
 	for _, test := range testCases {
 		t.Run(test.name, func(t *testing.T) {
-			scraper := newProcessesScraper(context.Background(), receivertest.NewNopCreateSettings(), &Config{
+			scraper := NewProcessesScraper(context.Background(), receivertest.NewNopCreateSettings(), &Config{
 				MetricsBuilderConfig: metadata.DefaultMetricsBuilderConfig(),
 			})
-			err := scraper.start(context.Background(), componenttest.NewNopHost())
+			err := scraper.Start(context.Background(), componenttest.NewNopHost())
 			assert.NoError(t, err, "Failed to initialize processes scraper: %v", err)
 
 			// Override scraper methods if we are mocking out for this test case
 			if test.getMiscStats != nil {
-				scraper.getMiscStats = test.getMiscStats
+				scraper.GetMiscStats = test.getMiscStats
 			}
 			if test.getProcesses != nil {
-				scraper.getProcesses = test.getProcesses
+				scraper.GetProcesses = test.getProcesses
 			}
 
-			md, err := scraper.scrape(context.Background())
+			md, err := scraper.Scrape(context.Background())
 
 			expectedMetricCount := 0
 			if expectProcessesCountMetric {
@@ -166,7 +166,7 @@ var fakeData = load.MiscStat{
 	ProcsTotal:   30,
 }
 
-var fakeProcessesData = []proc{
+var fakeProcessesData = []Proc{
 	fakeProcess(process.Wait),
 	fakeProcess(process.Blocked), fakeProcess(process.Blocked),
 	fakeProcess(process.Running), fakeProcess(process.Running), fakeProcess(process.Running),

receiver/hostmetricsreceiver/internal/scraper/processesscraper/processes_scraper_unix.go

@@ -18,9 +18,9 @@ import (
 const enableProcessesCount = true
 const enableProcessesCreated = runtime.GOOS == "openbsd" || runtime.GOOS == "linux"
 
-func (s *scraper) getProcessesMetadata() (processesMetadata, error) {
+func (s *Scraper) getProcessesMetadata() (processesMetadata, error) {
 	ctx := context.WithValue(context.Background(), common.EnvKey, s.config.EnvMap)
-	processes, err := s.getProcesses()
+	processes, err := s.GetProcesses()
 	if err != nil {
 		return processesMetadata{}, err
 	}
@@ -45,7 +45,7 @@ func (s *scraper) getProcessesMetadata() (processesMetadata, error) {
 	// Processes are actively changing as we run this code, so this reason
 	// the above loop will tend to underestimate process counts.
 	// getMiscStats is a single read/syscall so it should be more accurate.
-	miscStat, err := s.getMiscStats(ctx)
+	miscStat, err := s.GetMiscStats(ctx)
 	if err != nil {
 		return processesMetadata{}, err
 	}