Add profile spans for the network handshake inside RemoteModule#beforeCommand.

PiperOrigin-RevId: 538498468
Change-Id: I88cb9114bb370f42ecdeaac5b592b3a4e9ab4f08

Author: coeuvre

src/main/java/com/google/devtools/build/lib/remote/RemoteModule.java

@@ -59,6 +59,7 @@
 import com.google.devtools.build.lib.exec.ExecutorBuilder;
 import com.google.devtools.build.lib.exec.ModuleActionContextRegistry;
 import com.google.devtools.build.lib.exec.SpawnStrategyRegistry;
+import com.google.devtools.build.lib.profiler.Profiler;
 import com.google.devtools.build.lib.remote.RemoteServerCapabilities.ServerCapabilitiesRequirement;
 import com.google.devtools.build.lib.remote.circuitbreaker.CircuitBreakerFactory;
 import com.google.devtools.build.lib.remote.common.RemoteCacheClient;
@@ -443,45 +444,49 @@ public void beforeCommand(CommandEnvironment env) throws AbruptExitException {
     }
 
     if (enableRemoteExecution) {
-      ImmutableList.Builder<ClientInterceptor> interceptors = ImmutableList.builder();
-      interceptors.add(TracingMetadataUtils.newExecHeadersInterceptor(remoteOptions));
-      if (loggingInterceptor != null) {
-        interceptors.add(loggingInterceptor);
-      }
-      execChannel =
-          new ReferenceCountedChannel(
-              new GoogleChannelConnectionFactory(
-                  channelFactory,
-                  remoteOptions.remoteExecutor,
-                  remoteOptions.remoteProxy,
-                  authAndTlsOptions,
-                  interceptors.build(),
-                  maxConcurrencyPerConnection),
-              maxConnections);
-
-      // Create a separate channel if --remote_executor and --remote_cache point to different
-      // endpoints.
-      if (remoteOptions.remoteCache.equals(remoteOptions.remoteExecutor)) {
-        cacheChannel = execChannel.retain();
+      try (var s = Profiler.instance().profile("init exec channel")) {
+        ImmutableList.Builder<ClientInterceptor> interceptors = ImmutableList.builder();
+        interceptors.add(TracingMetadataUtils.newExecHeadersInterceptor(remoteOptions));
+        if (loggingInterceptor != null) {
+          interceptors.add(loggingInterceptor);
+        }
+        execChannel =
+            new ReferenceCountedChannel(
+                new GoogleChannelConnectionFactory(
+                    channelFactory,
+                    remoteOptions.remoteExecutor,
+                    remoteOptions.remoteProxy,
+                    authAndTlsOptions,
+                    interceptors.build(),
+                    maxConcurrencyPerConnection),
+                maxConnections);
+
+        // Create a separate channel if --remote_executor and --remote_cache point to different
+        // endpoints.
+        if (remoteOptions.remoteCache.equals(remoteOptions.remoteExecutor)) {
+          cacheChannel = execChannel.retain();
+        }
       }
     }
 
     if (cacheChannel == null) {
-      ImmutableList.Builder<ClientInterceptor> interceptors = ImmutableList.builder();
-      interceptors.add(TracingMetadataUtils.newCacheHeadersInterceptor(remoteOptions));
-      if (loggingInterceptor != null) {
-        interceptors.add(loggingInterceptor);
+      try (var s = Profiler.instance().profile("init cache channel")) {
+        ImmutableList.Builder<ClientInterceptor> interceptors = ImmutableList.builder();
+        interceptors.add(TracingMetadataUtils.newCacheHeadersInterceptor(remoteOptions));
+        if (loggingInterceptor != null) {
+          interceptors.add(loggingInterceptor);
+        }
+        cacheChannel =
+            new ReferenceCountedChannel(
+                new GoogleChannelConnectionFactory(
+                    channelFactory,
+                    remoteOptions.remoteCache,
+                    remoteOptions.remoteProxy,
+                    authAndTlsOptions,
+                    interceptors.build(),
+                    maxConcurrencyPerConnection),
+                maxConnections);
       }
-      cacheChannel =
-          new ReferenceCountedChannel(
-              new GoogleChannelConnectionFactory(
-                  channelFactory,
-                  remoteOptions.remoteCache,
-                  remoteOptions.remoteProxy,
-                  authAndTlsOptions,
-                  interceptors.build(),
-                  maxConcurrencyPerConnection),
-              maxConnections);
     }
 
     if (enableRemoteDownloader) {
@@ -526,7 +531,7 @@ public void beforeCommand(CommandEnvironment env) throws AbruptExitException {
     // capabilities respectively.
     ServerCapabilities executionCapabilities = null;
     ServerCapabilities cacheCapabilities = null;
-    try {
+    try (var s = Profiler.instance().profile("check server capabilities")) {
       if (execChannel != null) {
         if (cacheChannel != execChannel) {
           executionCapabilities =