[Chore][Master] Quietly exit WorkerGroupDispatcher loop on interrupt

dolphinscheduler-master/CLAUDE.md

@@ -52,7 +52,43 @@ Exposed interfaces:
 
 ## Tests
 
-`src/test/java` — unit + integration. Integration tests extend `AbstractMasterIntegrationTestCase`; they simulate distributed scenarios including failover.
+`src/test/java` — unit + integration. Integration tests extend `AbstractMasterIntegrationTestCase` (a `@SpringBootTest`) and live under `server/master/integration/cases/`; they simulate distributed scenarios including failover.
+
+### Running the suite
+
+From the repo root:
+
+```bash
+# Whole module (unit + integration). Use `clean` to avoid the JaCoCo
+# "Cannot process instrumented class" failure when classes from a previous
+# build are still on disk.
+./mvnw -pl dolphinscheduler-master -am clean test
+
+# Single test class. -Dsurefire.failIfNoSpecifiedTests=false is required
+# whenever -am pulls in upstream modules: the -Dtest filter applies to
+# every reactor module, and surefire fails the build on any module that
+# has zero matches without this flag.
+./mvnw -pl dolphinscheduler-master -am clean test \
+    -Dtest=WorkerGroupDispatcherTest \
+    -Dsurefire.failIfNoSpecifiedTests=false
+
+# Single method
+./mvnw -pl dolphinscheduler-master -am clean test \
+    -Dtest=WorkerGroupDispatcherTest#dispatch \
+    -Dsurefire.failIfNoSpecifiedTests=false
+```
+
+### Local environment
+
+- **No Docker required.** Integration tests boot Spring Boot against an in-memory H2 (`spring-it-application.yaml`), with a fake registry — Testcontainers is not used here. The repo-wide `-Dm1_chip=true` flag only applies to `dolphinscheduler-api-test` / `dolphinscheduler-e2e`; ignore it when running this module.
+- **Surefire forks 4 JVMs in parallel** (`forkCount=4`, `reuseForks=true`, see root `pom.xml`). Tests must therefore be parallel-safe — never share static mutable state across cases. Per-fork JaCoCo files land at `target/jacoco-${forkNumber}.exec`.
+- The `Surefire is going to kill self fork JVM. The exit has elapsed 30 seconds after System.exit(0).` line at the end is **a harmless warning** — `BUILD SUCCESS` on the same run is the real signal. It just means a fork held a non-daemon thread past `System.exit`; do not chase it unless the build itself fails.
+
+### When tests fail
+
+1. Re-run with `clean` first — the JaCoCo error above and stale generated sources both vanish after a clean rebuild.
+2. For integration tests, check `target/surefire-reports/*-output.txt` per fork — exceptions from the embedded master/H2 are logged there, not on stdout.
+3. New lifecycle events / failover paths must be exercised against `AbstractMasterIntegrationTestCase` (see the gotcha above) — extend an existing case under `integration/cases/` rather than writing a bare unit test.
 
 ## Related modules
 

dolphinscheduler-master/src/main/java/org/apache/dolphinscheduler/server/master/engine/task/dispatcher/TaskDispatchableEventBus.java

@@ -20,8 +20,6 @@
 import org.apache.dolphinscheduler.eventbus.AbstractDelayEventBus;
 import org.apache.dolphinscheduler.server.master.engine.task.dispatcher.event.TaskDispatchableEvent;
 
-import lombok.SneakyThrows;
-
 public class TaskDispatchableEventBus<V extends TaskDispatchableEvent<T>, T extends Comparable<T>>
         extends
             AbstractDelayEventBus<V> {
@@ -30,8 +28,8 @@
         super.publish(v);
     }
 
-    @SneakyThrows
-    public V take() {
+    @Override
+    public V take() throws InterruptedException {
         return super.take();
     }
 

dolphinscheduler-master/src/main/java/org/apache/dolphinscheduler/server/master/engine/task/dispatcher/WorkerGroupDispatcher.java

@@ -87,7 +87,14 @@ public synchronized void start() {
     @Override
     public void run() {
         while (runningFlag.get()) {
-            TaskDispatchableEvent<ITaskExecution> taskEntry = workerGroupEventBus.take();
+            final TaskDispatchableEvent<ITaskExecution> taskEntry;
+            try {
+                taskEntry = workerGroupEventBus.take();
+            } catch (InterruptedException e) {
+                Thread.currentThread().interrupt();
+                log.info("{} interrupted, exiting run loop", this.getName());
+                return;
+            }
             ITaskExecution taskExecution = taskEntry.getData();
             try (
                     TaskExecutorMDCUtils.MDCAutoClosable ignore =
@@ -123,9 +130,9 @@ private void doDispatchTask(ITaskExecution taskExecution) {
 
             // If dispatch failed, will put the task back to the queue
             // The task will be dispatched after waiting time.
-            // the waiting time will increase multiple of times, but will not exceed 60 seconds
-            long waitingTimeMillis = Math.min(
-                    taskExecution.getTaskExecutionContext().increaseDispatchFailTimes() * 1_000L, 60_000L);
+            // the waiting time grows with the fail count, bounded between 1 and 60 seconds
+            long waitingTimeMillis = Math.max(1_000L, Math.min(
+                    taskExecution.getTaskExecutionContext().increaseDispatchFailTimes() * 1_000L, 60_000L));
             dispatchTask(taskExecution, waitingTimeMillis);
             log.warn("Dispatch Task: {} failed will retry after: {}/ms", taskInstanceId,
                     waitingTimeMillis, ex);