Add 'standalone' in the defaults for --dynamic_local_strategy when …

…we have local lockfree. Once we have flipped and removed the local lockfree flag, this can just be the default.

PiperOrigin-RevId: 527854309
Change-Id: Ia934f794d7d6e32bb4f46df4e0966802390c1e09

src/main/java/com/google/devtools/build/lib/dynamic/BUILD

@@ -25,6 +25,7 @@ java_library(
         "//src/main/java/com/google/devtools/build/lib/exec:execution_options",
         "//src/main/java/com/google/devtools/build/lib/exec:execution_policy",
         "//src/main/java/com/google/devtools/build/lib/exec:spawn_strategy_registry",
+        "//src/main/java/com/google/devtools/build/lib/exec/local:options",
         "//src/main/java/com/google/devtools/build/lib/profiler",
         "//src/main/java/com/google/devtools/build/lib/util:abrupt_exit_exception",
         "//src/main/java/com/google/devtools/build/lib/util:detailed_exit_code",

src/main/java/com/google/devtools/build/lib/dynamic/DynamicExecutionModule.java

@@ -30,6 +30,7 @@
 import com.google.devtools.build.lib.events.Reporter;
 import com.google.devtools.build.lib.exec.ExecutionPolicy;
 import com.google.devtools.build.lib.exec.SpawnStrategyRegistry;
+import com.google.devtools.build.lib.exec.local.LocalExecutionOptions;
 import com.google.devtools.build.lib.runtime.BlazeModule;
 import com.google.devtools.build.lib.runtime.Command;
 import com.google.devtools.build.lib.runtime.CommandEnvironment;
@@ -56,6 +57,7 @@ public class DynamicExecutionModule extends BlazeModule {
   Set<Integer> ignoreLocalSignals = ImmutableSet.of();
   protected Reporter reporter;
   protected boolean verboseFailures;
+  private LocalExecutionOptions localOptions;
 
   public DynamicExecutionModule() {}
 
@@ -82,6 +84,7 @@ public void beforeCommand(CommandEnvironment env) {
     verboseFailures = executionOptions != null && executionOptions.verboseFailures;
     DynamicExecutionOptions dynamicOptions =
         env.getOptions().getOptions(DynamicExecutionOptions.class);
+    localOptions = env.getOptions().getOptions(LocalExecutionOptions.class);
     ignoreLocalSignals =
         dynamicOptions != null && dynamicOptions.ignoreLocalSignals != null
             ? dynamicOptions.ignoreLocalSignals
@@ -94,17 +97,19 @@ ImmutableMap<String, List<String>> getLocalStrategies(DynamicExecutionOptions op
       throws AbruptExitException {
     // Options that set "allowMultiple" to true ignore the default value, so we replicate that
     // functionality here.
-    // ImmutableMap.Builder fails on duplicates, so we use a regular map first to remove dups.
-    Map<String, List<String>> localAndWorkerStrategies = new HashMap<>();
-    localAndWorkerStrategies.put("", ImmutableList.of("worker", "sandboxed"));
+    ImmutableMap.Builder<String, List<String>> localAndWorkerStrategies = ImmutableMap.builder();
+    if (localOptions != null && localOptions.localLockfreeOutput) {
+      localAndWorkerStrategies.put("", ImmutableList.of("worker", "sandboxed", "standalone"));
+    } else {
+      // Without local lock free, having standalone execution risks very bad performance.
+      localAndWorkerStrategies.put("", ImmutableList.of("worker", "sandboxed"));
+    }
 
-    if (!options.dynamicLocalStrategy.isEmpty()) {
-      for (Map.Entry<String, List<String>> entry : options.dynamicLocalStrategy) {
-        localAndWorkerStrategies.put(entry.getKey(), entry.getValue());
-        throwIfContainsDynamic(entry.getValue(), "--dynamic_local_strategy");
-      }
+    for (Map.Entry<String, List<String>> entry : options.dynamicLocalStrategy) {
+      localAndWorkerStrategies.put(entry);
+      throwIfContainsDynamic(entry.getValue(), "--dynamic_local_strategy");
     }
-    return ImmutableMap.copyOf(localAndWorkerStrategies);
+    return localAndWorkerStrategies.buildKeepingLast();
   }
 
   private ImmutableMap<String, List<String>> getRemoteStrategies(DynamicExecutionOptions options)

src/main/java/com/google/devtools/build/lib/dynamic/DynamicExecutionOptions.java

@@ -78,7 +78,8 @@ public class DynamicExecutionOptions extends OptionsBase {
               + "strategy is used. For example, `worker,sandboxed` runs actions that support "
               + "persistent workers using the worker strategy, and all others using the sandboxed "
               + "strategy. If no mnemonic is given, the list of strategies is used as the "
-              + "fallback for all mnemonics. The default fallback list is `worker,sandboxed`. "
+              + "fallback for all mnemonics. The default fallback list is `worker,sandboxed`, or"
+              + "`worker,sandboxed,standalone` if `experimental_local_lockfree_output` is set. "
               + "Takes [mnemonic=]local_strategy[,local_strategy,...]")
   public List<Map.Entry<String, List<String>>> dynamicLocalStrategy;
 

src/main/java/com/google/devtools/build/lib/exec/local/LocalExecutionOptions.java

@@ -65,9 +65,9 @@ public class LocalExecutionOptions extends OptionsBase {
       documentationCategory = OptionDocumentationCategory.UNDOCUMENTED,
       effectTags = {OptionEffectTag.EXECUTION},
       help =
-          "When true, the local spawn runner does lock the output tree during dynamic execution. "
-              + "Instead, spawns are allowed to execute until they are explicitly interrupted by a "
-              + "faster remote action.")
+          "When true, the local spawn runner doesn't lock the output tree during dynamic "
+              + "execution. Instead, spawns are allowed to execute until they are explicitly "
+              + "interrupted by a faster remote action.")
   public boolean localLockfreeOutput;
 
   @Option(