feat: make trace provider in loadtest, add tracing to sdk (#4939)

agent/agent_test.go

@@ -58,9 +58,12 @@ func TestAgent(t *testing.T) {
 
 		t.Run("SSH", func(t *testing.T) {
 			t.Parallel()
+			ctx, cancel := context.WithTimeout(context.Background(), testutil.WaitLong)
+			defer cancel()
+
 			conn, stats := setupAgent(t, codersdk.WorkspaceAgentMetadata{}, 0)
 
-			sshClient, err := conn.SSHClient()
+			sshClient, err := conn.SSHClient(ctx)
 			require.NoError(t, err)
 			defer sshClient.Close()
 			session, err := sshClient.NewSession()
@@ -75,9 +78,12 @@ func TestAgent(t *testing.T) {
 		t.Run("ReconnectingPTY", func(t *testing.T) {
 			t.Parallel()
 
+			ctx, cancel := context.WithTimeout(context.Background(), testutil.WaitLong)
+			defer cancel()
+
 			conn, stats := setupAgent(t, codersdk.WorkspaceAgentMetadata{}, 0)
 
-			ptyConn, err := conn.ReconnectingPTY(uuid.NewString(), 128, 128, "/bin/bash")
+			ptyConn, err := conn.ReconnectingPTY(ctx, uuid.NewString(), 128, 128, "/bin/bash")
 			require.NoError(t, err)
 			defer ptyConn.Close()
 
@@ -217,6 +223,8 @@ func TestAgent(t *testing.T) {
 
 	t.Run("SFTP", func(t *testing.T) {
 		t.Parallel()
+		ctx, cancel := context.WithTimeout(context.Background(), testutil.WaitLong)
+		defer cancel()
 		u, err := user.Current()
 		require.NoError(t, err, "get current user")
 		home := u.HomeDir
@@ -224,7 +232,7 @@ func TestAgent(t *testing.T) {
 			home = "/" + strings.ReplaceAll(home, "\\", "/")
 		}
 		conn, _ := setupAgent(t, codersdk.WorkspaceAgentMetadata{}, 0)
-		sshClient, err := conn.SSHClient()
+		sshClient, err := conn.SSHClient(ctx)
 		require.NoError(t, err)
 		defer sshClient.Close()
 		client, err := sftp.NewClient(sshClient)
@@ -250,8 +258,11 @@ func TestAgent(t *testing.T) {
 	t.Run("SCP", func(t *testing.T) {
 		t.Parallel()
 
+		ctx, cancel := context.WithTimeout(context.Background(), testutil.WaitLong)
+		defer cancel()
+
 		conn, _ := setupAgent(t, codersdk.WorkspaceAgentMetadata{}, 0)
-		sshClient, err := conn.SSHClient()
+		sshClient, err := conn.SSHClient(ctx)
 		require.NoError(t, err)
 		defer sshClient.Close()
 		scpClient, err := scp.NewClientBySSH(sshClient)
@@ -386,9 +397,12 @@ func TestAgent(t *testing.T) {
 			t.Skip("ConPTY appears to be inconsistent on Windows.")
 		}
 
+		ctx, cancel := context.WithTimeout(context.Background(), testutil.WaitLong)
+		defer cancel()
+
 		conn, _ := setupAgent(t, codersdk.WorkspaceAgentMetadata{}, 0)
 		id := uuid.NewString()
-		netConn, err := conn.ReconnectingPTY(id, 100, 100, "/bin/bash")
+		netConn, err := conn.ReconnectingPTY(ctx, id, 100, 100, "/bin/bash")
 		require.NoError(t, err)
 		bufRead := bufio.NewReader(netConn)
 
@@ -426,7 +440,7 @@ func TestAgent(t *testing.T) {
 		expectLine(matchEchoOutput)
 
 		_ = netConn.Close()
-		netConn, err = conn.ReconnectingPTY(id, 100, 100, "/bin/bash")
+		netConn, err = conn.ReconnectingPTY(ctx, id, 100, 100, "/bin/bash")
 		require.NoError(t, err)
 		bufRead = bufio.NewReader(netConn)
 
@@ -504,12 +518,14 @@ func TestAgent(t *testing.T) {
 	t.Run("Speedtest", func(t *testing.T) {
 		t.Parallel()
 		t.Skip("This test is relatively flakey because of Tailscale's speedtest code...")
+		ctx, cancel := context.WithTimeout(context.Background(), testutil.WaitLong)
+		defer cancel()
 		derpMap := tailnettest.RunDERPAndSTUN(t)
 		conn, _ := setupAgent(t, codersdk.WorkspaceAgentMetadata{
 			DERPMap: derpMap,
 		}, 0)
 		defer conn.Close()
-		res, err := conn.Speedtest(speedtest.Upload, 250*time.Millisecond)
+		res, err := conn.Speedtest(ctx, speedtest.Upload, 250*time.Millisecond)
 		require.NoError(t, err)
 		t.Logf("%.2f MBits/s", res[len(res)-1].MBitsPerSecond())
 	})
@@ -599,7 +615,10 @@ func setupSSHCommand(t *testing.T, beforeArgs []string, afterArgs []string) *exe
 			if err != nil {
 				return
 			}
-			ssh, err := agentConn.SSH()
+
+			ctx, cancel := context.WithTimeout(context.Background(), testutil.WaitLong)
+			ssh, err := agentConn.SSH(ctx)
+			cancel()
 			if err != nil {
 				_ = conn.Close()
 				return
@@ -626,8 +645,10 @@ func setupSSHCommand(t *testing.T, beforeArgs []string, afterArgs []string) *exe
 }
 
 func setupSSHSession(t *testing.T, options codersdk.WorkspaceAgentMetadata) *ssh.Session {
+	ctx, cancel := context.WithTimeout(context.Background(), testutil.WaitLong)
+	defer cancel()
 	conn, _ := setupAgent(t, options, 0)
-	sshClient, err := conn.SSHClient()
+	sshClient, err := conn.SSHClient(ctx)
 	require.NoError(t, err)
 	t.Cleanup(func() {
 		_ = sshClient.Close()

cli/agent_test.go

@@ -198,7 +198,7 @@ func TestWorkspaceAgent(t *testing.T) {
 			return err == nil
 		}, testutil.WaitMedium, testutil.IntervalFast)
 
-		sshClient, err := dialer.SSHClient()
+		sshClient, err := dialer.SSHClient(ctx)
 		require.NoError(t, err)
 		defer sshClient.Close()
 		session, err := sshClient.NewSession()

cli/configssh_test.go

@@ -28,6 +28,7 @@ import (
 	"github.com/coder/coder/provisioner/echo"
 	"github.com/coder/coder/provisionersdk/proto"
 	"github.com/coder/coder/pty/ptytest"
+	"github.com/coder/coder/testutil"
 )
 
 func sshConfigFileName(t *testing.T) (sshConfig string) {
@@ -131,7 +132,9 @@ func TestConfigSSH(t *testing.T) {
 			if err != nil {
 				break
 			}
-			ssh, err := agentConn.SSH()
+			ctx, cancel := context.WithTimeout(context.Background(), testutil.WaitLong)
+			ssh, err := agentConn.SSH(ctx)
+			cancel()
 			assert.NoError(t, err)
 			wg.Add(2)
 			go func() {

cli/loadtest.go

@@ -8,20 +8,30 @@ import (
 	"os"
 	"strconv"
 	"strings"
+	"sync"
 	"time"
 
 	"github.com/spf13/cobra"
+	"go.opentelemetry.io/otel/trace"
 	"golang.org/x/xerrors"
 
 	"github.com/coder/coder/cli/cliflag"
+	"github.com/coder/coder/coderd/tracing"
 	"github.com/coder/coder/codersdk"
 	"github.com/coder/coder/loadtest/harness"
 )
 
+const loadtestTracerName = "coder_loadtest"
+
 func loadtest() *cobra.Command {
 	var (
 		configPath  string
 		outputSpecs []string
+
+		traceEnable          bool
+		traceCoder           bool
+		traceHoneycombAPIKey string
+		tracePropagate       bool
 	)
 	cmd := &cobra.Command{
 		Use:   "loadtest --config <path> [--output json[:path]] [--output text[:path]]]",
@@ -53,6 +63,8 @@ func loadtest() *cobra.Command {
 		Hidden: true,
 		Args:   cobra.ExactArgs(0),
 		RunE: func(cmd *cobra.Command, args []string) error {
+			ctx := tracing.SetTracerName(cmd.Context(), loadtestTracerName)
+
 			config, err := loadLoadTestConfigFile(configPath, cmd.InOrStdin())
 			if err != nil {
 				return err
@@ -67,7 +79,7 @@ func loadtest() *cobra.Command {
 				return err
 			}
 
-			me, err := client.User(cmd.Context(), codersdk.Me)
+			me, err := client.User(ctx, codersdk.Me)
 			if err != nil {
 				return xerrors.Errorf("fetch current user: %w", err)
 			}
@@ -84,11 +96,43 @@ func loadtest() *cobra.Command {
 				}
 			}
 			if !ok {
-				return xerrors.Errorf("Not logged in as site owner. Load testing is only available to site owners.")
+				return xerrors.Errorf("Not logged in as a site owner. Load testing is only available to site owners.")
 			}
 
-			// Disable ratelimits for future requests.
+			// Setup tracing and start a span.
+			var (
+				shouldTrace                           = traceEnable || traceCoder || traceHoneycombAPIKey != ""
+				tracerProvider   trace.TracerProvider = trace.NewNoopTracerProvider()
+				closeTracingOnce sync.Once
+				closeTracing     = func(_ context.Context) error {
+					return nil
+				}
+			)
+			if shouldTrace {
+				tracerProvider, closeTracing, err = tracing.TracerProvider(ctx, loadtestTracerName, tracing.TracerOpts{
+					Default:   traceEnable,
+					Coder:     traceCoder,
+					Honeycomb: traceHoneycombAPIKey,
+				})
+				if err != nil {
+					return xerrors.Errorf("initialize tracing: %w", err)
+				}
+				defer func() {
+					closeTracingOnce.Do(func() {
+						// Allow time for traces to flush even if command
+						// context is canceled.
+						ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
+						defer cancel()
+						_ = closeTracing(ctx)
+					})
+				}()
+			}
+			tracer := tracerProvider.Tracer(loadtestTracerName)
+
+			// Disable ratelimits and propagate tracing spans for future
+			// requests. Individual tests will setup their own loggers.
 			client.BypassRatelimits = true
+			client.PropagateTracing = tracePropagate
 
 			// Prepare the test.
 			strategy := config.Strategy.ExecutionStrategy()
@@ -99,18 +143,22 @@ func loadtest() *cobra.Command {
 
 				for j := 0; j < t.Count; j++ {
 					id := strconv.Itoa(j)
-					runner, err := t.NewRunner(client)
+					runner, err := t.NewRunner(client.Clone())
 					if err != nil {
 						return xerrors.Errorf("create %q runner for %s/%s: %w", t.Type, name, id, err)
 					}
 
-					th.AddRun(name, id, runner)
+					th.AddRun(name, id, &runnableTraceWrapper{
+						tracer:   tracer,
+						spanName: fmt.Sprintf("%s/%s", name, id),
+						runner:   runner,
+					})
 				}
 			}
 
 			_, _ = fmt.Fprintln(cmd.ErrOrStderr(), "Running load test...")
 
-			testCtx := cmd.Context()
+			testCtx := ctx
 			if config.Timeout > 0 {
 				var cancel func()
 				testCtx, cancel = context.WithTimeout(testCtx, time.Duration(config.Timeout))
@@ -158,11 +206,24 @@ func loadtest() *cobra.Command {
 
 			// Cleanup.
 			_, _ = fmt.Fprintln(cmd.ErrOrStderr(), "\nCleaning up...")
-			err = th.Cleanup(cmd.Context())
+			err = th.Cleanup(ctx)
 			if err != nil {
 				return xerrors.Errorf("cleanup tests: %w", err)
 			}
 
+			// Upload traces.
+			if shouldTrace {
+				_, _ = fmt.Fprintln(cmd.ErrOrStderr(), "\nUploading traces...")
+				closeTracingOnce.Do(func() {
+					ctx, cancel := context.WithTimeout(ctx, 1*time.Minute)
+					defer cancel()
+					err := closeTracing(ctx)
+					if err != nil {
+						_, _ = fmt.Fprintf(cmd.ErrOrStderr(), "\nError uploading traces: %+v\n", err)
+					}
+				})
+			}
+
 			if res.TotalFail > 0 {
 				return xerrors.New("load test failed, see above for more details")
 			}
@@ -173,6 +234,12 @@ func loadtest() *cobra.Command {
 
 	cliflag.StringVarP(cmd.Flags(), &configPath, "config", "", "CODER_LOADTEST_CONFIG_PATH", "", "Path to the load test configuration file, or - to read from stdin.")
 	cliflag.StringArrayVarP(cmd.Flags(), &outputSpecs, "output", "", "CODER_LOADTEST_OUTPUTS", []string{"text"}, "Output formats, see usage for more information.")
+
+	cliflag.BoolVarP(cmd.Flags(), &traceEnable, "trace", "", "CODER_LOADTEST_TRACE", false, "Whether application tracing data is collected. It exports to a backend configured by environment variables. See: https://github.com/open-telemetry/opentelemetry-specification/blob/main/specification/protocol/exporter.md")
+	cliflag.BoolVarP(cmd.Flags(), &traceCoder, "trace-coder", "", "CODER_LOADTEST_TRACE_CODER", false, "Whether opentelemetry traces are sent to Coder. We recommend keeping this disabled unless we advise you to enable it.")
+	cliflag.StringVarP(cmd.Flags(), &traceHoneycombAPIKey, "trace-honeycomb-api-key", "", "CODER_LOADTEST_TRACE_HONEYCOMB_API_KEY", "", "Enables trace exporting to Honeycomb.io using the provided API key.")
+	cliflag.BoolVarP(cmd.Flags(), &tracePropagate, "trace-propagate", "", "CODER_LOADTEST_TRACE_PROPAGATE", false, "Enables trace propagation to the Coder backend, which will be used to correlate server-side spans with client-side spans. Only enable this if the server is configured with the exact same tracing configuration as the client.")
+
 	return cmd
 }
 
@@ -271,3 +338,53 @@ func parseLoadTestOutputs(outputs []string) ([]loadTestOutput, error) {
 
 	return out, nil
 }
+
+type runnableTraceWrapper struct {
+	tracer   trace.Tracer
+	spanName string
+	runner   harness.Runnable
+
+	span trace.Span
+}
+
+var _ harness.Runnable = &runnableTraceWrapper{}
+var _ harness.Cleanable = &runnableTraceWrapper{}
+
+func (r *runnableTraceWrapper) Run(ctx context.Context, id string, logs io.Writer) error {
+	ctx, span := r.tracer.Start(ctx, r.spanName, trace.WithNewRoot())
+	defer span.End()
+	r.span = span
+
+	traceID := "unknown trace ID"
+	spanID := "unknown span ID"
+	if span.SpanContext().HasTraceID() {
+		traceID = span.SpanContext().TraceID().String()
+	}
+	if span.SpanContext().HasSpanID() {
+		spanID = span.SpanContext().SpanID().String()
+	}
+	_, _ = fmt.Fprintf(logs, "Trace ID: %s\n", traceID)
+	_, _ = fmt.Fprintf(logs, "Span ID: %s\n\n", spanID)
+
+	// Make a separate span for the run itself so the sub-spans are grouped
+	// neatly. The cleanup span is also a child of the above span so this is
+	// important for readability.
+	ctx2, span2 := r.tracer.Start(ctx, r.spanName+" run")
+	defer span2.End()
+	return r.runner.Run(ctx2, id, logs)
+}
+
+func (r *runnableTraceWrapper) Cleanup(ctx context.Context, id string) error {
+	c, ok := r.runner.(harness.Cleanable)
+	if !ok {
+		return nil
+	}
+
+	if r.span != nil {
+		ctx = trace.ContextWithSpanContext(ctx, r.span.SpanContext())
+	}
+	ctx, span := r.tracer.Start(ctx, r.spanName+" cleanup")
+	defer span.End()
+
+	return c.Cleanup(ctx, id)
+}

cli/loadtest_test.go

@@ -277,6 +277,8 @@ func TestLoadTest(t *testing.T) {
 						require.NoError(t, err, msg)
 					}
 
+					t.Logf("output %d:\n\n%s", i, string(b))
+
 					switch output.format {
 					case "text":
 						require.Contains(t, string(b), "Test results:", msg)

cli/server.go

@@ -130,6 +130,7 @@ func Server(vip *viper.Viper, newAPI func(context.Context, *coderd.Options) (*co
 				sdkTracerProvider, closeTracing, err := tracing.TracerProvider(ctx, "coderd", tracing.TracerOpts{
 					Default:   cfg.Trace.Enable.Value,
 					Coder:     shouldCoderTrace,
+					Honeycomb: cfg.Trace.HoneycombAPIKey.Value,
 				})
 				if err != nil {
 					logger.Warn(ctx, "start telemetry exporter", slog.Error(err))

cli/speedtest.go

@@ -95,7 +95,7 @@ func speedtest() *cobra.Command {
 				dir = tsspeedtest.Upload
 			}
 			cmd.Printf("Starting a %ds %s test...\n", int(duration.Seconds()), dir)
-			results, err := conn.Speedtest(dir, duration)
+			results, err := conn.Speedtest(ctx, dir, duration)
 			if err != nil {
 				return err
 			}

cli/ssh.go

@@ -100,7 +100,7 @@ func ssh() *cobra.Command {
 			defer stopPolling()
 
 			if stdio {
-				rawSSH, err := conn.SSH()
+				rawSSH, err := conn.SSH(ctx)
 				if err != nil {
 					return err
 				}
@@ -113,7 +113,7 @@ func ssh() *cobra.Command {
 				return nil
 			}
 
-			sshClient, err := conn.SSHClient()
+			sshClient, err := conn.SSHClient(ctx)
 			if err != nil {
 				return err
 			}

coderd/activitybump_test.go

@@ -88,7 +88,7 @@ func TestWorkspaceActivityBump(t *testing.T) {
 		require.NoError(t, err)
 		defer conn.Close()
 
-		sshConn, err := conn.SSHClient()
+		sshConn, err := conn.SSHClient(ctx)
 		require.NoError(t, err)
 		_ = sshConn.Close()
 

coderd/templates_test.go

@@ -633,7 +633,7 @@ func TestTemplateMetrics(t *testing.T) {
 		_ = conn.Close()
 	}()
 
-	sshConn, err := conn.SSHClient()
+	sshConn, err := conn.SSHClient(ctx)
 	require.NoError(t, err)
 	_ = sshConn.Close()
 

coderd/tracing/exporter.go

@@ -4,6 +4,7 @@ import (
 	"context"
 
 	"github.com/go-logr/logr"
+	"github.com/hashicorp/go-multierror"
 	"go.opentelemetry.io/otel"
 	"go.opentelemetry.io/otel/exporters/otlp/otlptrace"
 	"go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracegrpc"
@@ -82,11 +83,23 @@ func TracerProvider(ctx context.Context, service string, opts TracerOpts) (*sdkt
 	otel.SetLogger(logr.Discard())
 
 	return tracerProvider, func(ctx context.Context) error {
-		for _, close := range closers {
+		var merr error
-			_ = close(ctx)
+		err := tracerProvider.ForceFlush(ctx)
+		if err != nil {
+			merr = multierror.Append(merr, xerrors.Errorf("tracerProvider.ForceFlush(): %w", err))
 		}
-		_ = tracerProvider.Shutdown(ctx)
+		for i, closer := range closers {
-		return nil
+			err = closer(ctx)
+			if err != nil {
+				merr = multierror.Append(merr, xerrors.Errorf("closer() %d: %w", i, err))
+			}
+		}
+		err = tracerProvider.Shutdown(ctx)
+		if err != nil {
+			merr = multierror.Append(merr, xerrors.Errorf("tracerProvider.Shutdown(): %w", err))
+		}
+
+		return merr
 	}, nil
 }
 

coderd/tracing/httpmw.go

@@ -6,6 +6,8 @@ import (
 	"net/http"
 
 	"github.com/go-chi/chi/v5"
+	"go.opentelemetry.io/otel"
+	"go.opentelemetry.io/otel/propagation"
 	semconv "go.opentelemetry.io/otel/semconv/v1.11.0"
 	"go.opentelemetry.io/otel/trace"
 )
@@ -23,11 +25,27 @@ func Middleware(tracerProvider trace.TracerProvider) func(http.Handler) http.Han
 				return
 			}
 
+			// Extract the trace context from the request headers.
+			tmp := otel.GetTextMapPropagator()
+			hc := propagation.HeaderCarrier(r.Header)
+			ctx := tmp.Extract(r.Context(), hc)
+
 			// start span with default span name. Span name will be updated to "method route" format once request finishes.
-			ctx, span := tracer.Start(r.Context(), fmt.Sprintf("%s %s", r.Method, r.RequestURI))
+			ctx, span := tracer.Start(ctx, fmt.Sprintf("%s %s", r.Method, r.RequestURI))
 			defer span.End()
 			r = r.WithContext(ctx)
 
+			if span.SpanContext().HasTraceID() && span.SpanContext().HasSpanID() {
+				// Technically these values are included in the Traceparent
+				// header, but they are easier to read for humans this way.
+				rw.Header().Set("X-Trace-ID", span.SpanContext().TraceID().String())
+				rw.Header().Set("X-Span-ID", span.SpanContext().SpanID().String())
+
+				// Inject the trace context into the response headers.
+				hc := propagation.HeaderCarrier(rw.Header())
+				tmp.Inject(ctx, hc)
+			}
+
 			sw, ok := rw.(*StatusWriter)
 			if !ok {
 				panic(fmt.Sprintf("ResponseWriter not a *tracing.StatusWriter; got %T", rw))
@@ -62,6 +80,37 @@ func EndHTTPSpan(r *http.Request, status int, span trace.Span) {
 	span.End()
 }
 
-func StartSpan(ctx context.Context, opts ...trace.SpanStartOption) (context.Context, trace.Span) {
+type tracerNameKey struct{}
-	return trace.SpanFromContext(ctx).TracerProvider().Tracer(TracerName).Start(ctx, FuncNameSkip(1), opts...)
+
+// SetTracerName sets the tracer name that will be used by all spans created
+// from the context.
+func SetTracerName(ctx context.Context, tracerName string) context.Context {
+	return context.WithValue(ctx, tracerNameKey{}, tracerName)
+}
+
+// GetTracerName returns the tracer name from the context, or TracerName if none
+// is set.
+func GetTracerName(ctx context.Context) string {
+	if tracerName, ok := ctx.Value(tracerNameKey{}).(string); ok {
+		return tracerName
+	}
+
+	return TracerName
+}
+
+// StartSpan calls StartSpanWithName with the name set to the caller's function
+// name.
+func StartSpan(ctx context.Context, opts ...trace.SpanStartOption) (context.Context, trace.Span) {
+	return StartSpanWithName(ctx, FuncNameSkip(1), opts...)
+}
+
+// StartSpanWithName starts a new span with the given name from the context. If
+// a tracer name was set on the context (or one of its parents), it will be used
+// as the tracer name instead of the default TracerName.
+func StartSpanWithName(ctx context.Context, name string, opts ...trace.SpanStartOption) (context.Context, trace.Span) {
+	tracerName := GetTracerName(ctx)
+	return trace.SpanFromContext(ctx).
+		TracerProvider().
+		Tracer(tracerName).
+		Start(ctx, name, opts...)
 }

coderd/workspaceagents.go

@@ -247,7 +247,7 @@ func (api *API) workspaceAgentPTY(rw http.ResponseWriter, r *http.Request) {
 		return
 	}
 	defer release()
-	ptNetConn, err := agentConn.ReconnectingPTY(reconnect.String(), uint16(height), uint16(width), r.URL.Query().Get("command"))
+	ptNetConn, err := agentConn.ReconnectingPTY(ctx, reconnect.String(), uint16(height), uint16(width), r.URL.Query().Get("command"))
 	if err != nil {
 		_ = conn.Close(websocket.StatusInternalError, httpapi.WebsocketCloseSprintf("dial: %s", err))
 		return

coderd/workspaceagents_test.go

@@ -260,7 +260,7 @@ func TestWorkspaceAgentTailnet(t *testing.T) {
 	})
 	require.NoError(t, err)
 	defer conn.Close()
-	sshClient, err := conn.SSHClient()
+	sshClient, err := conn.SSHClient(ctx)
 	require.NoError(t, err)
 	session, err := sshClient.NewSession()
 	require.NoError(t, err)

codersdk/agentconn.go

@@ -20,6 +20,7 @@ import (
 	"tailscale.com/net/speedtest"
 	"tailscale.com/tailcfg"
 
+	"github.com/coder/coder/coderd/tracing"
 	"github.com/coder/coder/tailnet"
 )
 
@@ -133,6 +134,9 @@ type AgentConn struct {
 }
 
 func (c *AgentConn) Ping(ctx context.Context) (time.Duration, error) {
+	ctx, span := tracing.StartSpan(ctx)
+	defer span.End()
+
 	errCh := make(chan error, 1)
 	durCh := make(chan time.Duration, 1)
 	go c.Conn.Ping(TailnetIP, tailcfg.PingDisco, func(pr *ipnstate.PingResult) {
@@ -171,8 +175,11 @@ type ReconnectingPTYInit struct {
 	Command string
 }
 
-func (c *AgentConn) ReconnectingPTY(id string, height, width uint16, command string) (net.Conn, error) {
+func (c *AgentConn) ReconnectingPTY(ctx context.Context, id string, height, width uint16, command string) (net.Conn, error) {
-	conn, err := c.DialContextTCP(context.Background(), netip.AddrPortFrom(TailnetIP, uint16(TailnetReconnectingPTYPort)))
+	ctx, span := tracing.StartSpan(ctx)
+	defer span.End()
+
+	conn, err := c.DialContextTCP(ctx, netip.AddrPortFrom(TailnetIP, uint16(TailnetReconnectingPTYPort)))
 	if err != nil {
 		return nil, err
 	}
@@ -197,14 +204,18 @@ func (c *AgentConn) ReconnectingPTY(id string, height, width uint16, command str
 	return conn, nil
 }
 
-func (c *AgentConn) SSH() (net.Conn, error) {
+func (c *AgentConn) SSH(ctx context.Context) (net.Conn, error) {
-	return c.DialContextTCP(context.Background(), netip.AddrPortFrom(TailnetIP, uint16(TailnetSSHPort)))
+	ctx, span := tracing.StartSpan(ctx)
+	defer span.End()
+	return c.DialContextTCP(ctx, netip.AddrPortFrom(TailnetIP, uint16(TailnetSSHPort)))
 }
 
 // SSHClient calls SSH to create a client that uses a weak cipher
 // for high throughput.
-func (c *AgentConn) SSHClient() (*ssh.Client, error) {
+func (c *AgentConn) SSHClient(ctx context.Context) (*ssh.Client, error) {
-	netConn, err := c.SSH()
+	ctx, span := tracing.StartSpan(ctx)
+	defer span.End()
+	netConn, err := c.SSH(ctx)
 	if err != nil {
 		return nil, xerrors.Errorf("ssh: %w", err)
 	}
@@ -220,8 +231,10 @@ func (c *AgentConn) SSHClient() (*ssh.Client, error) {
 	return ssh.NewClient(sshConn, channels, requests), nil
 }
 
-func (c *AgentConn) Speedtest(direction speedtest.Direction, duration time.Duration) ([]speedtest.Result, error) {
+func (c *AgentConn) Speedtest(ctx context.Context, direction speedtest.Direction, duration time.Duration) ([]speedtest.Result, error) {
-	speedConn, err := c.DialContextTCP(context.Background(), netip.AddrPortFrom(TailnetIP, uint16(TailnetSpeedtestPort)))
+	ctx, span := tracing.StartSpan(ctx)
+	defer span.End()
+	speedConn, err := c.DialContextTCP(ctx, netip.AddrPortFrom(TailnetIP, uint16(TailnetSpeedtestPort)))
 	if err != nil {
 		return nil, xerrors.Errorf("dial speedtest: %w", err)
 	}
@@ -233,6 +246,8 @@ func (c *AgentConn) Speedtest(direction speedtest.Direction, duration time.Durat
 }
 
 func (c *AgentConn) DialContext(ctx context.Context, network string, addr string) (net.Conn, error) {
+	ctx, span := tracing.StartSpan(ctx)
+	defer span.End()
 	if network == "unix" {
 		return nil, xerrors.New("network must be tcp or udp")
 	}
@@ -277,6 +292,8 @@ func (c *AgentConn) statisticsClient() *http.Client {
 }
 
 func (c *AgentConn) doStatisticsRequest(ctx context.Context, method, path string, body io.Reader) (*http.Response, error) {
+	ctx, span := tracing.StartSpan(ctx)
+	defer span.End()
 	host := net.JoinHostPort(TailnetIP.String(), strconv.Itoa(TailnetStatisticsPort))
 	url := fmt.Sprintf("http://%s%s", host, path)
 
@@ -309,6 +326,8 @@ type ListeningPort struct {
 }
 
 func (c *AgentConn) ListeningPorts(ctx context.Context) (ListeningPortsResponse, error) {
+	ctx, span := tracing.StartSpan(ctx)
+	defer span.End()
 	res, err := c.doStatisticsRequest(ctx, http.MethodGet, "/api/v0/listening-ports", nil)
 	if err != nil {
 		return ListeningPortsResponse{}, xerrors.Errorf("do request: %w", err)

codersdk/client.go

@@ -12,7 +12,15 @@ import (
 	"net/url"
 	"strings"
 
+	"go.opentelemetry.io/otel"
+	"go.opentelemetry.io/otel/propagation"
+	semconv "go.opentelemetry.io/otel/semconv/v1.11.0"
+	"go.opentelemetry.io/otel/trace"
 	"golang.org/x/xerrors"
+
+	"github.com/coder/coder/coderd/tracing"
+
+	"cdr.dev/slog"
 )
 
 // These cookies are Coder-specific. If a new one is added or changed, the name
@@ -30,6 +38,13 @@ const (
 	BypassRatelimitHeader = "X-Coder-Bypass-Ratelimit"
 )
 
+var loggableMimeTypes = map[string]struct{}{
+	"application/json": {},
+	"text/plain":       {},
+	// lots of webserver error pages are HTML
+	"text/html": {},
+}
+
 // New creates a Coder client for the provided URL.
 func New(serverURL *url.URL) *Client {
 	return &Client{
@@ -45,9 +60,35 @@ type Client struct {
 	SessionToken string
 	URL          *url.URL
 
+	// Logger can be provided to log requests. Request method, URL and response
+	// status code will be logged by default.
+	Logger slog.Logger
+	// LogBodies determines whether the request and response bodies are logged
+	// to the provided Logger. This is useful for debugging or testing.
+	LogBodies bool
+
 	// BypassRatelimits is an optional flag that can be set by the site owner to
 	// disable ratelimit checks for the client.
 	BypassRatelimits bool
+
+	// PropagateTracing is an optional flag that can be set to propagate tracing
+	// spans to the Coder API. This is useful for seeing the entire request
+	// from end-to-end.
+	PropagateTracing bool
+}
+
+func (c *Client) Clone() *Client {
+	hc := *c.HTTPClient
+	u := *c.URL
+	return &Client{
+		HTTPClient:       &hc,
+		SessionToken:     c.SessionToken,
+		URL:              &u,
+		Logger:           c.Logger,
+		LogBodies:        c.LogBodies,
+		BypassRatelimits: c.BypassRatelimits,
+		PropagateTracing: c.PropagateTracing,
+	}
 }
 
 type RequestOption func(*http.Request)
@@ -63,30 +104,46 @@ func WithQueryParam(key, value string) RequestOption {
 	}
 }
 
-// Request performs an HTTP request with the body provided.
+// Request performs a HTTP request with the body provided. The caller is
-// The caller is responsible for closing the response body.
+// responsible for closing the response body.
 func (c *Client) Request(ctx context.Context, method, path string, body interface{}, opts ...RequestOption) (*http.Response, error) {
+	ctx, span := tracing.StartSpanWithName(ctx, tracing.FuncNameSkip(1))
+	defer span.End()
+
 	serverURL, err := c.URL.Parse(path)
 	if err != nil {
 		return nil, xerrors.Errorf("parse url: %w", err)
 	}
 
-	var buf bytes.Buffer
+	var r io.Reader
 	if body != nil {
 		if data, ok := body.([]byte); ok {
-			buf = *bytes.NewBuffer(data)
+			r = bytes.NewReader(data)
 		} else {
 			// Assume JSON if not bytes.
-			enc := json.NewEncoder(&buf)
+			buf := bytes.NewBuffer(nil)
+			enc := json.NewEncoder(buf)
 			enc.SetEscapeHTML(false)
 			err = enc.Encode(body)
 			if err != nil {
 				return nil, xerrors.Errorf("encode body: %w", err)
 			}
+
+			r = buf
 		}
 	}
 
-	req, err := http.NewRequestWithContext(ctx, method, serverURL.String(), &buf)
+	// Copy the request body so we can log it.
+	var reqBody []byte
+	if r != nil && c.LogBodies {
+		reqBody, err = io.ReadAll(r)
+		if err != nil {
+			return nil, xerrors.Errorf("read request body: %w", err)
+		}
+		r = bytes.NewReader(reqBody)
+	}
+
+	req, err := http.NewRequestWithContext(ctx, method, serverURL.String(), r)
 	if err != nil {
 		return nil, xerrors.Errorf("create request: %w", err)
 	}
@@ -95,17 +152,61 @@ func (c *Client) Request(ctx context.Context, method, path string, body interfac
 		req.Header.Set(BypassRatelimitHeader, "true")
 	}
 
-	if body != nil {
+	if r != nil {
 		req.Header.Set("Content-Type", "application/json")
 	}
 	for _, opt := range opts {
 		opt(req)
 	}
 
+	span.SetAttributes(semconv.NetAttributesFromHTTPRequest("tcp", req)...)
+	span.SetAttributes(semconv.HTTPClientAttributesFromHTTPRequest(req)...)
+
+	// Inject tracing headers if enabled.
+	if c.PropagateTracing {
+		tmp := otel.GetTextMapPropagator()
+		hc := propagation.HeaderCarrier(req.Header)
+		tmp.Inject(ctx, hc)
+	}
+
+	ctx = slog.With(ctx,
+		slog.F("method", req.Method),
+		slog.F("url", req.URL.String()),
+	)
+	c.Logger.Debug(ctx, "sdk request", slog.F("body", string(reqBody)))
+
 	resp, err := c.HTTPClient.Do(req)
 	if err != nil {
 		return nil, xerrors.Errorf("do: %w", err)
 	}
+
+	span.SetAttributes(semconv.HTTPStatusCodeKey.Int(resp.StatusCode))
+	span.SetStatus(semconv.SpanStatusFromHTTPStatusCodeAndSpanKind(resp.StatusCode, trace.SpanKindClient))
+
+	// Copy the response body so we can log it if it's a loggable mime type.
+	var respBody []byte
+	if resp.Body != nil && c.LogBodies {
+		mimeType := parseMimeType(resp.Header.Get("Content-Type"))
+		if _, ok := loggableMimeTypes[mimeType]; ok {
+			respBody, err = io.ReadAll(resp.Body)
+			if err != nil {
+				return nil, xerrors.Errorf("copy response body for logs: %w", err)
+			}
+			err = resp.Body.Close()
+			if err != nil {
+				return nil, xerrors.Errorf("close response body: %w", err)
+			}
+			resp.Body = io.NopCloser(bytes.NewReader(respBody))
+		}
+	}
+
+	c.Logger.Debug(ctx, "sdk response",
+		slog.F("status", resp.StatusCode),
+		slog.F("body", string(respBody)),
+		slog.F("trace_id", resp.Header.Get("X-Trace-Id")),
+		slog.F("span_id", resp.Header.Get("X-Span-Id")),
+	)
+
 	return resp, err
 }
 
@@ -138,10 +239,7 @@ func readBodyAsError(res *http.Response) error {
 		return xerrors.Errorf("read body: %w", err)
 	}
 
-	mimeType, _, err := mime.ParseMediaType(contentType)
+	mimeType := parseMimeType(contentType)
-	if err != nil {
-		mimeType = strings.TrimSpace(strings.Split(contentType, ";")[0])
-	}
 	if mimeType != "application/json" {
 		if len(resp) > 1024 {
 			resp = append(resp[:1024], []byte("...")...)
@@ -238,3 +336,12 @@ type closeFunc func() error
 func (c closeFunc) Close() error {
 	return c()
 }
+
+func parseMimeType(contentType string) string {
+	mimeType, _, err := mime.ParseMediaType(contentType)
+	if err != nil {
+		mimeType = strings.TrimSpace(strings.Split(contentType, ";")[0])
+	}
+
+	return mimeType
+}

codersdk/client_internal_test.go

@@ -2,23 +2,114 @@ package codersdk
 
 import (
 	"bytes"
+	"context"
 	"encoding/json"
 	"fmt"
 	"io"
 	"net/http"
 	"net/http/httptest"
+	"net/url"
 	"strconv"
 	"strings"
 	"testing"
 
+	"github.com/go-logr/logr"
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
+	"go.opentelemetry.io/otel"
+	"go.opentelemetry.io/otel/propagation"
+	"go.opentelemetry.io/otel/sdk/resource"
+	sdktrace "go.opentelemetry.io/otel/sdk/trace"
+	semconv "go.opentelemetry.io/otel/semconv/v1.4.0"
 	"golang.org/x/xerrors"
+
+	"cdr.dev/slog"
+	"cdr.dev/slog/sloggers/sloghuman"
+
+	"github.com/coder/coder/testutil"
 )
 
-const (
+const jsonCT = "application/json"
-	jsonCT = "application/json"
+
+func Test_Client(t *testing.T) {
+	t.Parallel()
+
+	const method = http.MethodPost
+	const path = "/ok"
+	const token = "token"
+	const reqBody = `{"msg": "request body"}`
+	const resBody = `{"status": "ok"}`
+
+	s := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		assert.Equal(t, method, r.Method)
+		assert.Equal(t, path, r.URL.Path)
+		assert.Equal(t, token, r.Header.Get(SessionCustomHeader))
+		assert.Equal(t, "true", r.Header.Get(BypassRatelimitHeader))
+		assert.NotEmpty(t, r.Header.Get("Traceparent"))
+		for k, v := range r.Header {
+			t.Logf("header %q: %q", k, strings.Join(v, ", "))
+		}
+
+		w.Header().Set("Content-Type", jsonCT)
+		w.WriteHeader(http.StatusOK)
+		_, _ = io.WriteString(w, resBody)
+	}))
+
+	u, err := url.Parse(s.URL)
+	require.NoError(t, err)
+	client := New(u)
+	client.SessionToken = token
+	client.BypassRatelimits = true
+
+	logBuf := bytes.NewBuffer(nil)
+	client.Logger = slog.Make(sloghuman.Sink(logBuf)).Leveled(slog.LevelDebug)
+	client.LogBodies = true
+
+	// Setup tracing.
+	res := resource.NewWithAttributes(
+		semconv.SchemaURL,
+		semconv.ServiceNameKey.String("codersdk_test"),
 	)
+	tracerOpts := []sdktrace.TracerProviderOption{
+		sdktrace.WithResource(res),
+	}
+	tracerProvider := sdktrace.NewTracerProvider(tracerOpts...)
+	otel.SetTracerProvider(tracerProvider)
+	otel.SetErrorHandler(otel.ErrorHandlerFunc(func(err error) {}))
+	otel.SetTextMapPropagator(
+		propagation.NewCompositeTextMapPropagator(
+			propagation.TraceContext{},
+			propagation.Baggage{},
+		),
+	)
+	otel.SetLogger(logr.Discard())
+	client.PropagateTracing = true
+
+	ctx, cancel := context.WithTimeout(context.Background(), testutil.WaitLong)
+	defer cancel()
+	ctx, span := tracerProvider.Tracer("codersdk_test").Start(ctx, "codersdk client test 1")
+	defer span.End()
+
+	resp, err := client.Request(ctx, method, path, []byte(reqBody))
+	require.NoError(t, err)
+	defer resp.Body.Close()
+
+	require.Equal(t, http.StatusOK, resp.StatusCode)
+	require.Equal(t, jsonCT, resp.Header.Get("Content-Type"))
+
+	body, err := io.ReadAll(resp.Body)
+	require.NoError(t, err)
+	require.Equal(t, resBody, string(body))
+
+	logStr := logBuf.String()
+	require.Contains(t, logStr, "sdk request")
+	require.Contains(t, logStr, method)
+	require.Contains(t, logStr, path)
+	require.Contains(t, logStr, strings.ReplaceAll(reqBody, `"`, `\"`))
+	require.Contains(t, logStr, "sdk response")
+	require.Contains(t, logStr, "200")
+	require.Contains(t, logStr, strings.ReplaceAll(resBody, `"`, `\"`))
+}
 
 func Test_readBodyAsError(t *testing.T) {
 	t.Parallel()

codersdk/sse.go

@@ -2,11 +2,14 @@ package codersdk
 
 import (
 	"bufio"
+	"context"
 	"fmt"
 	"io"
 	"strings"
 
 	"golang.org/x/xerrors"
+
+	"github.com/coder/coder/coderd/tracing"
 )
 
 type ServerSentEvent struct {
@@ -22,7 +25,10 @@ const (
 	ServerSentEventTypeError ServerSentEventType = "error"
 )
 
-func ServerSentEventReader(rc io.ReadCloser) func() (*ServerSentEvent, error) {
+func ServerSentEventReader(ctx context.Context, rc io.ReadCloser) func() (*ServerSentEvent, error) {
+	_, span := tracing.StartSpan(ctx)
+	defer span.End()
+
 	reader := bufio.NewReader(rc)
 	nextLineValue := func(prefix string) ([]byte, error) {
 		var (

codersdk/workspaces.go

@@ -10,6 +10,8 @@ import (
 
 	"github.com/google/uuid"
 	"golang.org/x/xerrors"
+
+	"github.com/coder/coder/coderd/tracing"
 )
 
 // Workspace is a deployment of a template. It references a specific
@@ -137,6 +139,8 @@ func (c *Client) CreateWorkspaceBuild(ctx context.Context, workspace uuid.UUID,
 }
 
 func (c *Client) WatchWorkspace(ctx context.Context, id uuid.UUID) (<-chan Workspace, error) {
+	ctx, span := tracing.StartSpan(ctx)
+	defer span.End()
 	//nolint:bodyclose
 	res, err := c.Request(ctx, http.MethodGet, fmt.Sprintf("/api/v2/workspaces/%s/watch", id), nil)
 	if err != nil {
@@ -145,7 +149,7 @@ func (c *Client) WatchWorkspace(ctx context.Context, id uuid.UUID) (<-chan Works
 	if res.StatusCode != http.StatusOK {
 		return nil, readBodyAsError(res)
 	}
-	nextEvent := ServerSentEventReader(res.Body)
+	nextEvent := ServerSentEventReader(ctx, res.Body)
 
 	wc := make(chan Workspace, 256)
 	go func() {

loadtest/agentconn/run.go

@@ -9,7 +9,6 @@ import (
 	"net/netip"
 	"net/url"
 	"strconv"
-	"sync"
 	"time"
 
 	"golang.org/x/sync/errgroup"
@@ -17,8 +16,10 @@ import (
 
 	"cdr.dev/slog"
 	"cdr.dev/slog/sloggers/sloghuman"
+	"github.com/coder/coder/coderd/tracing"
 	"github.com/coder/coder/codersdk"
 	"github.com/coder/coder/loadtest/harness"
+	"github.com/coder/coder/loadtest/loadtestutil"
 )
 
 const defaultRequestTimeout = 5 * time.Second
@@ -45,11 +46,13 @@ func NewRunner(client *codersdk.Client, cfg Config) *Runner {
 
 // Run implements Runnable.
 func (r *Runner) Run(ctx context.Context, _ string, logs io.Writer) error {
-	logs = syncWriter{
+	ctx, span := tracing.StartSpan(ctx)
-		mut: &sync.Mutex{},
+	defer span.End()
-		w:   logs,
+
-	}
+	logs = loadtestutil.NewSyncWriter(logs)
 	logger := slog.Make(sloghuman.Sink(logs)).Leveled(slog.LevelDebug)
+	r.client.Logger = logger
+	r.client.LogBodies = true
 
 	_, _ = fmt.Fprintln(logs, "Opening connection to workspace agent")
 	switch r.cfg.ConnectionMode {
@@ -69,9 +72,72 @@ func (r *Runner) Run(ctx context.Context, _ string, logs io.Writer) error {
 	}
 	defer conn.Close()
 
-	// Wait for the disco connection to be established.
+	err = waitForDisco(ctx, logs, conn)
+	if err != nil {
+		return xerrors.Errorf("wait for discovery connection: %w", err)
+	}
+
+	// Wait for a direct connection if requested.
+	if r.cfg.ConnectionMode == ConnectionModeDirect {
+		err = waitForDirectConnection(ctx, logs, conn)
+		if err != nil {
+			return xerrors.Errorf("wait for direct connection: %w", err)
+		}
+	}
+
+	// Ensure DERP for completeness.
+	if r.cfg.ConnectionMode == ConnectionModeDerp {
+		status := conn.Status()
+		if len(status.Peers()) != 1 {
+			return xerrors.Errorf("check connection mode: expected 1 peer, got %d", len(status.Peers()))
+		}
+		peer := status.Peer[status.Peers()[0]]
+		if peer.Relay == "" || peer.CurAddr != "" {
+			return xerrors.Errorf("check connection mode: peer is connected directly, not via DERP")
+		}
+	}
+
+	_, _ = fmt.Fprint(logs, "\nConnection established.\n\n")
+
+	// HACK: even though the ping passed above, we still need to open a
+	// connection to the agent to ensure it's ready to accept connections. Not
+	// sure why this is the case but it seems to be necessary.
+	err = verifyConnection(ctx, logs, conn)
+	if err != nil {
+		return xerrors.Errorf("verify connection: %w", err)
+	}
+
+	_, _ = fmt.Fprint(logs, "\nConnection verified.\n\n")
+
+	// Make initial connections sequentially to ensure the services are
+	// reachable before we start spawning a bunch of goroutines and tickers.
+	err = performInitialConnections(ctx, logs, conn, r.cfg.Connections)
+	if err != nil {
+		return xerrors.Errorf("perform initial connections: %w", err)
+	}
+
+	if r.cfg.HoldDuration > 0 {
+		err = holdConnection(ctx, logs, conn, time.Duration(r.cfg.HoldDuration), r.cfg.Connections)
+		if err != nil {
+			return xerrors.Errorf("hold connection: %w", err)
+		}
+	}
+
+	err = conn.Close()
+	if err != nil {
+		return xerrors.Errorf("close connection: %w", err)
+	}
+
+	return nil
+}
+
+func waitForDisco(ctx context.Context, logs io.Writer, conn *codersdk.AgentConn) error {
 	const pingAttempts = 10
 	const pingDelay = 1 * time.Second
+
+	ctx, span := tracing.StartSpan(ctx)
+	defer span.End()
+
 	for i := 0; i < pingAttempts; i++ {
 		_, _ = fmt.Fprintf(logs, "\tDisco ping attempt %d/%d...\n", i+1, pingAttempts)
 		pingCtx, cancel := context.WithTimeout(ctx, defaultRequestTimeout)
@@ -93,10 +159,16 @@ func (r *Runner) Run(ctx context.Context, _ string, logs io.Writer) error {
 		}
 	}
 
-	// Wait for a direct connection if requested.
+	return nil
-	if r.cfg.ConnectionMode == ConnectionModeDirect {
+}
+
+func waitForDirectConnection(ctx context.Context, logs io.Writer, conn *codersdk.AgentConn) error {
 	const directConnectionAttempts = 30
 	const directConnectionDelay = 1 * time.Second
+
+	ctx, span := tracing.StartSpan(ctx)
+	defer span.End()
+
 	for i := 0; i < directConnectionAttempts; i++ {
 		_, _ = fmt.Fprintf(logs, "\tDirect connection check %d/%d...\n", i+1, directConnectionAttempts)
 		status := conn.Status()
@@ -128,45 +200,18 @@ func (r *Runner) Run(ctx context.Context, _ string, logs io.Writer) error {
 		case <-time.After(directConnectionDelay):
 		}
 	}
+
+	return nil
 }
 
-	// Ensure DERP for completeness.
+func verifyConnection(ctx context.Context, logs io.Writer, conn *codersdk.AgentConn) error {
-	if r.cfg.ConnectionMode == ConnectionModeDerp {
-		status := conn.Status()
-		if len(status.Peers()) != 1 {
-			return xerrors.Errorf("check connection mode: expected 1 peer, got %d", len(status.Peers()))
-		}
-		peer := status.Peer[status.Peers()[0]]
-		if peer.Relay == "" || peer.CurAddr != "" {
-			return xerrors.Errorf("check connection mode: peer is connected directly, not via DERP")
-		}
-	}
-
-	_, _ = fmt.Fprint(logs, "\nConnection established.\n\n")
-
-	client := &http.Client{
-		Transport: &http.Transport{
-			DisableKeepAlives: true,
-			DialContext: func(ctx context.Context, network, addr string) (net.Conn, error) {
-				_, port, err := net.SplitHostPort(addr)
-				if err != nil {
-					return nil, xerrors.Errorf("split host port %q: %w", addr, err)
-				}
-
-				portUint, err := strconv.ParseUint(port, 10, 16)
-				if err != nil {
-					return nil, xerrors.Errorf("parse port %q: %w", port, err)
-				}
-				return conn.DialContextTCP(ctx, netip.AddrPortFrom(codersdk.TailnetIP, uint16(portUint)))
-			},
-		},
-	}
-
-	// HACK: even though the ping passed above, we still need to open a
-	// connection to the agent to ensure it's ready to accept connections. Not
-	// sure why this is the case but it seems to be necessary.
 	const verifyConnectionAttempts = 30
 	const verifyConnectionDelay = 1 * time.Second
+
+	ctx, span := tracing.StartSpan(ctx)
+	defer span.End()
+
+	client := agentHTTPClient(conn)
 	for i := 0; i < verifyConnectionAttempts; i++ {
 		_, _ = fmt.Fprintf(logs, "\tVerify connection attempt %d/%d...\n", i+1, verifyConnectionAttempts)
 		verifyCtx, cancel := context.WithTimeout(ctx, defaultRequestTimeout)
@@ -198,14 +243,20 @@ func (r *Runner) Run(ctx context.Context, _ string, logs io.Writer) error {
 		}
 	}
 
-	_, _ = fmt.Fprint(logs, "\nConnection verified.\n\n")
+	return nil
-
-	// Make initial connections sequentially to ensure the services are
-	// reachable before we start spawning a bunch of goroutines and tickers.
-	if len(r.cfg.Connections) > 0 {
-		_, _ = fmt.Fprintln(logs, "Performing initial service connections...")
 }
-	for i, connSpec := range r.cfg.Connections {
+
+func performInitialConnections(ctx context.Context, logs io.Writer, conn *codersdk.AgentConn, specs []Connection) error {
+	if len(specs) == 0 {
+		return nil
+	}
+
+	ctx, span := tracing.StartSpan(ctx)
+	defer span.End()
+
+	_, _ = fmt.Fprintln(logs, "Performing initial service connections...")
+	client := agentHTTPClient(conn)
+	for i, connSpec := range specs {
 		_, _ = fmt.Fprintf(logs, "\t%d. %s\n", i, connSpec.URL)
 
 		timeout := defaultRequestTimeout
@@ -230,13 +281,19 @@ func (r *Runner) Run(ctx context.Context, _ string, logs io.Writer) error {
 		_, _ = fmt.Fprintln(logs, "\t\tOK")
 	}
 
-	if r.cfg.HoldDuration > 0 {
+	return nil
-		eg, egCtx := errgroup.WithContext(ctx)
+}
 
-		if len(r.cfg.Connections) > 0 {
+func holdConnection(ctx context.Context, logs io.Writer, conn *codersdk.AgentConn, holdDur time.Duration, specs []Connection) error {
+	ctx, span := tracing.StartSpan(ctx)
+	defer span.End()
+
+	eg, egCtx := errgroup.WithContext(ctx)
+	client := agentHTTPClient(conn)
+	if len(specs) > 0 {
 		_, _ = fmt.Fprintln(logs, "\nStarting connection loops...")
 	}
-		for i, connSpec := range r.cfg.Connections {
+	for i, connSpec := range specs {
 		i, connSpec := i, connSpec
 		if connSpec.Interval <= 0 {
 			continue
@@ -280,9 +337,9 @@ func (r *Runner) Run(ctx context.Context, _ string, logs io.Writer) error {
 
 	// Wait for the hold duration to end. We use a fake error to signal that
 	// the hold duration has ended.
-		_, _ = fmt.Fprintf(logs, "\nWaiting for %s...\n", time.Duration(r.cfg.HoldDuration))
+	_, _ = fmt.Fprintf(logs, "\nWaiting for %s...\n", holdDur)
 	eg.Go(func() error {
-			t := time.NewTicker(time.Duration(r.cfg.HoldDuration))
+		t := time.NewTicker(holdDur)
 		defer t.Stop()
 
 		select {
@@ -296,29 +353,30 @@ func (r *Runner) Run(ctx context.Context, _ string, logs io.Writer) error {
 		}
 	})
 
-		err = eg.Wait()
+	err := eg.Wait()
 	if err != nil && !xerrors.Is(err, holdDurationEndedError{}) {
 		return xerrors.Errorf("run connections loop: %w", err)
 	}
-	}
-
-	err = conn.Close()
-	if err != nil {
-		return xerrors.Errorf("close connection: %w", err)
-	}
 
 	return nil
 }
 
-// syncWriter wraps an io.Writer in a sync.Mutex.
+func agentHTTPClient(conn *codersdk.AgentConn) *http.Client {
-type syncWriter struct {
+	return &http.Client{
-	mut *sync.Mutex
+		Transport: &http.Transport{
-	w   io.Writer
+			DisableKeepAlives: true,
+			DialContext: func(ctx context.Context, network, addr string) (net.Conn, error) {
+				_, port, err := net.SplitHostPort(addr)
+				if err != nil {
+					return nil, xerrors.Errorf("split host port %q: %w", addr, err)
 				}
 
-// Write implements io.Writer.
+				portUint, err := strconv.ParseUint(port, 10, 16)
-func (sw syncWriter) Write(p []byte) (n int, err error) {
+				if err != nil {
-	sw.mut.Lock()
+					return nil, xerrors.Errorf("parse port %q: %w", port, err)
-	defer sw.mut.Unlock()
+				}
-	return sw.w.Write(p)
+				return conn.DialContextTCP(ctx, netip.AddrPortFrom(codersdk.TailnetIP, uint16(portUint)))
+			},
+		},
+	}
 }

loadtest/harness/harness.go

@@ -7,6 +7,8 @@ import (
 
 	"github.com/hashicorp/go-multierror"
 	"golang.org/x/xerrors"
+
+	"github.com/coder/coder/coderd/tracing"
 )
 
 // ExecutionStrategy defines how a TestHarness should execute a set of runs. It
@@ -49,6 +51,9 @@ func NewTestHarness(strategy ExecutionStrategy) *TestHarness {
 //
 // Panics if called more than once.
 func (h *TestHarness) Run(ctx context.Context) (err error) {
+	ctx, span := tracing.StartSpan(ctx)
+	defer span.End()
+
 	h.mut.Lock()
 	if h.started {
 		h.mut.Unlock()

loadtest/harness/strategies.go

@@ -95,6 +95,7 @@ type timeoutRunnerWrapper struct {
 }
 
 var _ Runnable = timeoutRunnerWrapper{}
+var _ Cleanable = timeoutRunnerWrapper{}
 
 func (t timeoutRunnerWrapper) Run(ctx context.Context, id string, logs io.Writer) error {
 	ctx, cancel := context.WithTimeout(ctx, t.timeout)
@@ -103,6 +104,15 @@ func (t timeoutRunnerWrapper) Run(ctx context.Context, id string, logs io.Writer
 	return t.inner.Run(ctx, id, logs)
 }
 
+func (t timeoutRunnerWrapper) Cleanup(ctx context.Context, id string) error {
+	c, ok := t.inner.(Cleanable)
+	if !ok {
+		return nil
+	}
+
+	return c.Cleanup(ctx, id)
+}
+
 // Execute implements ExecutionStrategy.
 func (t TimeoutExecutionStrategyWrapper) Execute(ctx context.Context, runs []*TestRun) error {
 	for _, run := range runs {

loadtest/loadtestutil/syncwriter.go

@@ -0,0 +1,26 @@
+package loadtestutil
+
+import (
+	"io"
+	"sync"
+)
+
+// SyncWriter wraps an io.Writer in a sync.Mutex.
+type SyncWriter struct {
+	mut *sync.Mutex
+	w   io.Writer
+}
+
+func NewSyncWriter(w io.Writer) *SyncWriter {
+	return &SyncWriter{
+		mut: &sync.Mutex{},
+		w:   w,
+	}
+}
+
+// Write implements io.Writer.
+func (sw *SyncWriter) Write(p []byte) (n int, err error) {
+	sw.mut.Lock()
+	defer sw.mut.Unlock()
+	return sw.w.Write(p)
+}

loadtest/workspacebuild/run.go

@@ -9,9 +9,14 @@ import (
 	"github.com/google/uuid"
 	"golang.org/x/xerrors"
 
+	"cdr.dev/slog"
+	"cdr.dev/slog/sloggers/sloghuman"
+
+	"github.com/coder/coder/coderd/tracing"
 	"github.com/coder/coder/codersdk"
 	"github.com/coder/coder/cryptorand"
 	"github.com/coder/coder/loadtest/harness"
+	"github.com/coder/coder/loadtest/loadtestutil"
 )
 
 type Runner struct {
@@ -32,6 +37,14 @@ func NewRunner(client *codersdk.Client, cfg Config) *Runner {
 
 // Run implements Runnable.
 func (r *Runner) Run(ctx context.Context, _ string, logs io.Writer) error {
+	ctx, span := tracing.StartSpan(ctx)
+	defer span.End()
+
+	logs = loadtestutil.NewSyncWriter(logs)
+	logger := slog.Make(sloghuman.Sink(logs)).Leveled(slog.LevelDebug)
+	r.client.Logger = logger
+	r.client.LogBodies = true
+
 	req := r.cfg.Request
 	if req.Name == "" {
 		randName, err := cryptorand.HexString(8)
@@ -66,6 +79,8 @@ func (r *Runner) Cleanup(ctx context.Context, _ string) error {
 	if r.workspaceID == uuid.Nil {
 		return nil
 	}
+	ctx, span := tracing.StartSpan(ctx)
+	defer span.End()
 
 	build, err := r.client.CreateWorkspaceBuild(ctx, r.workspaceID, codersdk.CreateWorkspaceBuildRequest{
 		Transition: codersdk.WorkspaceTransitionDelete,
@@ -85,6 +100,8 @@ func (r *Runner) Cleanup(ctx context.Context, _ string) error {
 }
 
 func waitForBuild(ctx context.Context, w io.Writer, client *codersdk.Client, buildID uuid.UUID) error {
+	ctx, span := tracing.StartSpan(ctx)
+	defer span.End()
 	_, _ = fmt.Fprint(w, "Build is currently queued...")
 
 	// Wait for build to start.
@@ -154,6 +171,8 @@ func waitForBuild(ctx context.Context, w io.Writer, client *codersdk.Client, bui
 }
 
 func waitForAgents(ctx context.Context, w io.Writer, client *codersdk.Client, workspaceID uuid.UUID) error {
+	ctx, span := tracing.StartSpan(ctx)
+	defer span.End()
 	_, _ = fmt.Fprint(w, "Waiting for agents to connect...\n\n")
 
 	for {