KAFKA-19054: StreamThread exception handling with SHUTDOWN_APPLICATION may trigger a tight loop with MANY logs (#19394)

Under the `SHUTDOWN_APPLICATION` configuration in Kafka Streams, a tight
loop in the shutdown process can flood logs with repeated messages. This
PR introduces a check to ensure that the shutdown log is emitted only
once every 10 seconds, thereby preventing log flooding.

Reviewers: PoAn Yang <[email protected]>, Matthias J. Sax <[email protected]>

Author: apalan60

streams/integration-tests/src/test/java/org/apache/kafka/streams/integration/StreamsUncaughtExceptionHandlerIntegrationTest.java

@@ -23,6 +23,8 @@
 import org.apache.kafka.common.serialization.Serdes;
 import org.apache.kafka.common.serialization.StringDeserializer;
 import org.apache.kafka.common.serialization.StringSerializer;
+import org.apache.kafka.common.utils.LogCaptureAppender;
+import org.apache.kafka.common.utils.MockTime;
 import org.apache.kafka.streams.KafkaStreams;
 import org.apache.kafka.streams.KeyValue;
 import org.apache.kafka.streams.StreamsBuilder;
@@ -39,10 +41,12 @@
 import org.apache.kafka.streams.processor.api.Processor;
 import org.apache.kafka.streams.processor.api.ProcessorContext;
 import org.apache.kafka.streams.processor.api.Record;
+import org.apache.kafka.streams.processor.internals.StreamThread;
 import org.apache.kafka.streams.state.Stores;
 import org.apache.kafka.streams.state.internals.KeyValueStoreBuilder;
 import org.apache.kafka.test.TestUtils;
 
+import org.apache.logging.log4j.Level;
 import org.junit.jupiter.api.AfterAll;
 import org.junit.jupiter.api.AfterEach;
 import org.junit.jupiter.api.BeforeAll;
@@ -331,18 +335,23 @@ private void testShutdownApplication(final int numThreads) throws Exception {
         properties.put(StreamsConfig.NUM_STREAM_THREADS_CONFIG, numThreads);
 
         final Topology topology = builder.build();
-
-        try (final KafkaStreams kafkaStreams1 = new KafkaStreams(topology, properties);
-             final KafkaStreams kafkaStreams2 = new KafkaStreams(topology, properties)) {
+        final MockTime time = new MockTime(0L);
+        
+        try (final KafkaStreams kafkaStreams1 = new KafkaStreams(topology, properties, time);
+             final KafkaStreams kafkaStreams2 = new KafkaStreams(topology, properties, time);
+             final LogCaptureAppender logCaptureAppender = LogCaptureAppender.createAndRegister()) {
             kafkaStreams1.setUncaughtExceptionHandler(exception -> SHUTDOWN_APPLICATION);
             kafkaStreams2.setUncaughtExceptionHandler(exception -> SHUTDOWN_APPLICATION);
+            logCaptureAppender.setClassLogger(StreamThread.class, Level.WARN);
 
             startApplicationAndWaitUntilRunning(asList(kafkaStreams1, kafkaStreams2));
 
             produceMessages(NOW, inputTopic, "A");
             waitForApplicationState(asList(kafkaStreams1, kafkaStreams2), KafkaStreams.State.ERROR, DEFAULT_DURATION);
 
             assertThat(processorValueCollector.size(), equalTo(1));
+            assertThat("Shutdown warning log message should be exported exactly once",
+                    logCaptureAppender.getMessages("WARN").stream().filter(msg -> msg.contains("Detected that shutdown was requested")).count(), equalTo(1L));
         }
     }
 

streams/src/main/java/org/apache/kafka/streams/processor/internals/StreamThread.java

@@ -357,6 +357,7 @@ public boolean isStartingRunningOrPartitionAssigned() {
     // These are used to signal from outside the stream thread, but the variables themselves are internal to the thread
     private final AtomicLong cacheResizeSize = new AtomicLong(-1L);
     private final AtomicBoolean leaveGroupRequested = new AtomicBoolean(false);
+    private final AtomicLong lastShutdownWarningTimestamp = new AtomicLong(0L);
     private final boolean eosEnabled;
     private final boolean stateUpdaterEnabled;
     private final boolean processingThreadsEnabled;
@@ -1029,8 +1030,14 @@ public void setStreamsUncaughtExceptionHandler(final BiConsumer<Throwable, Boole
 
     public void maybeSendShutdown() {
         if (assignmentErrorCode.get() == AssignorError.SHUTDOWN_REQUESTED.code()) {
-            log.warn("Detected that shutdown was requested. " +
-                    "All clients in this app will now begin to shutdown");
+            final long now = time.milliseconds();
+            final long lastLogged = lastShutdownWarningTimestamp.get();
+            if (now - lastLogged >= 10_000L) {
+                if (lastShutdownWarningTimestamp.compareAndSet(lastLogged, now)) {
+                    log.warn("Detected that shutdown was requested. " +
+                            "All clients in this app will now begin to shutdown");
+                }
+            }
             mainConsumer.enforceRebalance("Shutdown requested");
         }
     }