Record and log some timings in orchestrator init function (#224)

* Record and log some timings in orchestrator init function

* Add changelog entry

Author: christian-stephen

CHANGELOG.md

@@ -10,6 +10,7 @@ By following these guidelines, we can easily determine which changes should be i
 
 ## Edge
 
+- [#224](https://github.com/circleci/runner-init/pull/224) Record and log timings in orchestrator init function.
 - [#212](https://github.com/circleci/runner-init/pull/212) Fix child process cleanup on Windows using job objects. This ensures that child processes are destroyed when the parent process (task-agent) terminates.
 - [#197](https://github.com/circleci/runner-init/pull/197) Fix `%PATH%` on Windows by using the OS-specific path list separator.
 - [#133](https://github.com/circleci/runner-init/pull/133) Don't re-handle task errors. If GOAT handles a task error (either with an infra-fail or retry), don't exit with a nonzero status code. Doing so causes container agent to overwrite the original error message in the UI.

cmd/orchestrator/main.go

@@ -84,7 +84,7 @@ func run(version, date string) (err error) {
 		c := cli.Init
 		sys.AddService(func(_ context.Context) error {
 			defer cancel()
-			return initialize.Run(c.Source, c.Destination)
+			return initialize.Run(ctx, c.Source, c.Destination)
 		})
 
 	case "run-task":

init/init.go

@@ -1,26 +1,34 @@
 package init
 
 import (
+	"context"
 	"errors"
 	"io"
 	"os"
 	"path/filepath"
 	"runtime"
+
+	"github.com/circleci/ex/o11y"
 )
 
 // Run function performs the copying of the orchestrator and task-agent binaries
-func Run(srcDir, destDir string) error {
+func Run(ctx context.Context, srcDir, destDir string) (err error) {
+	ctx, span := o11y.StartSpan(ctx, "orchestrator: init")
+	defer o11y.End(span, &err)
+
+	span.RecordMetric(o11y.Timing("init.duration"))
+
 	// Copy the orchestrator binary
 	orchestratorSrc := filepath.Join(srcDir, binOrchestrator)
 	orchestratorDest := filepath.Join(destDir, binOrchestrator)
-	if err := copyFile(orchestratorSrc, orchestratorDest); err != nil {
+	if err := copyFile(ctx, orchestratorSrc, orchestratorDest); err != nil {
 		return err
 	}
 
 	// Copy the task agent binary
 	agentSrc := filepath.Join(srcDir, binCircleciAgent)
 	agentDest := filepath.Join(destDir, binCircleciAgent)
-	if err := copyFile(agentSrc, agentDest); err != nil {
+	if err := copyFile(ctx, agentSrc, agentDest); err != nil {
 		return err
 	}
 
@@ -33,15 +41,21 @@ func Run(srcDir, destDir string) error {
 	} else {
 		// We copy the binary instead of creating a symlink to `circleci` as we do on Linux,
 		// since we do not have the necessary privileges to create symlinks to the shared volume on Windows.
-		if err := copyFile(agentSrc, circleciDest); err != nil {
+		if err := copyFile(ctx, agentSrc, circleciDest); err != nil {
 			return err
 		}
 	}
 
 	return nil
 }
 
-func copyFile(srcPath, destPath string) (err error) {
+func copyFile(ctx context.Context, srcPath, destPath string) (err error) {
+	_, span := o11y.StartSpan(ctx, "orchestrator: init: copy")
+	defer o11y.End(span, &err)
+
+	span.AddField("binary", filepath.Base(srcPath))
+	span.RecordMetric(o11y.Timing("init.copy.duration"))
+
 	closeFile := func(f *os.File) {
 		err = errors.Join(err, f.Close())
 	}

init/init_test.go

@@ -6,6 +6,7 @@ import (
 	"runtime"
 	"testing"
 
+	"github.com/circleci/ex/testing/testcontext"
 	"gotest.tools/v3/assert"
 	"gotest.tools/v3/assert/cmp"
 )
@@ -18,9 +19,10 @@ func TestRun(t *testing.T) {
 	agentSrc := filepath.Join(srcDir, binCircleciAgent)
 	agentDest := filepath.Join(destDir, binCircleciAgent)
 	circleciDest := filepath.Join(destDir, binCircleci)
+	ctx := testcontext.Background()
 
 	t.Run("Copy files and create symlink", func(t *testing.T) {
-		err := Run(srcDir, destDir)
+		err := Run(ctx, srcDir, destDir)
 		assert.NilError(t, err)
 
 		assertFileIsCopied(t, orchSrc, orchDest)
@@ -36,7 +38,7 @@ func TestRun(t *testing.T) {
 	})
 
 	t.Run("Fail when source files not present", func(t *testing.T) {
-		err := Run(srcDir, "non-existent-dir")
+		err := Run(ctx, srcDir, "non-existent-dir")
 		if runtime.GOOS == "windows" {
 			assert.Check(t, cmp.ErrorContains(err, "The system cannot find the path specified"))
 		} else {