mjsax commented on code in PR #16922:
URL: https://github.com/apache/kafka/pull/16922#discussion_r1733748420
##########
streams/src/main/java/org/apache/kafka/streams/processor/internals/StateDirectory.java:
##########
@@ -182,6 +199,120 @@ private boolean lockStateDirectory() {
return stateDirLock != null;
}
+ public void initializeTasksForLocalState(final TopologyMetadata
topologyMetadata, final StreamsMetricsImpl streamsMetrics) {
+ final List<TaskDirectory> nonEmptyTaskDirectories =
listNonEmptyTaskDirectories();
+ if (hasPersistentStores && !nonEmptyTaskDirectories.isEmpty()) {
+ final LogContext logContext = new LogContext("main-thread ");
+ final ThreadCache dummyCache = new ThreadCache(logContext, 0,
streamsMetrics);
+ final boolean eosEnabled = StreamsConfigUtils.eosEnabled(config);
+ final boolean stateUpdaterEnabled =
StreamsConfig.InternalConfig.stateUpdaterEnabled(config.originals());
+
+ // discover all non-empty task directories in StateDirectory
+ for (final TaskDirectory taskDirectory : nonEmptyTaskDirectories) {
+ final String dirName = taskDirectory.file().getName();
+ final TaskId id = parseTaskDirectoryName(dirName,
taskDirectory.namedTopology());
+ final ProcessorTopology topology =
topologyMetadata.buildSubtopology(id);
+ final Set<TopicPartition> inputPartitions =
topology.sourceTopics().stream().map(topic -> new TopicPartition(topic,
id.partition())).collect(Collectors.toSet());
+
+ // create a StandbyTask for each one
+ if (topology.hasStateWithChangelogs()) {
+ final ProcessorStateManager stateManager = new
ProcessorStateManager(
+ id,
+ Task.TaskType.STANDBY,
+ eosEnabled,
+ logContext,
+ this,
+ null,
+ topology.storeToChangelogTopic(),
+ inputPartitions,
+ stateUpdaterEnabled
+ );
+
+ final InternalProcessorContext<Object, Object> context =
new ProcessorContextImpl(
+ id,
+ config,
+ stateManager,
+ streamsMetrics,
+ dummyCache
+ );
+
+ final Task task = new StandbyTask(
+ id,
+ inputPartitions,
+ topology,
+ topologyMetadata.taskConfig(id),
+ streamsMetrics,
+ stateManager,
+ this,
+ dummyCache,
+ context
+ );
+
+ // initialize and suspend new Tasks
+ try {
+ task.initializeIfNeeded();
+ task.suspend();
+
+ // add new Tasks to tasksForLocalState
+ tasksForLocalState.put(id, task);
+ } catch (final TaskCorruptedException e) {
+ // Task is corrupt - wipe it out (under EOS) and don't
initialize a Standby for it
+ task.suspend();
+ task.closeDirty();
+ }
+ }
+ }
+ }
+ }
+
+ public boolean hasInitialTasks() {
+ return !tasksForLocalState.isEmpty();
+ }
+
+ public Task assignInitialTask(final TaskId taskId) {
+ final Task task = tasksForLocalState.remove(taskId);
+ if (task != null) {
+ lockedTasksToOwner.replace(taskId, Thread.currentThread());
+ }
+ return task;
+ }
+
+ public void closeInitialTasksIfLastAssginedThread() {
+ if (hasInitialTasks() && threadsWithAssignment.incrementAndGet() >=
config.getInt(StreamsConfig.NUM_STREAM_THREADS_CONFIG)) {
+ // we need to be careful here, because other StreamThreads may
still be assigning tasks (via assignInitialTask)
+ // so we first "drain" our Map of all remaining Tasks, and then
close all the Tasks we successfully claimed from the Map
+ final Set<Task> tasksToClose = drainInitialTasks();
+ for (final Task task : tasksToClose) {
+ task.closeClean();
+ }
+ }
+ }
+
+ private void closeRemainingInitialTasks() {
+ closeRemainingInitialTasks(t -> true);
+ }
+
+ private void closeRemainingInitialTasks(final Predicate<Task> predicate) {
+ final Set<Task> drainedTasks = drainInitialTasks(predicate);
+ for (final Task task : drainedTasks) {
+ task.closeClean();
+ }
+ }
+
+ private Set<Task> drainInitialTasks() {
+ return drainInitialTasks(t -> true);
+ }
+
+ private Set<Task> drainInitialTasks(final Predicate<Task> predicate) {
+ final Set<Task> drainedTasks = new
HashSet<>(tasksForLocalState.size());
+ for (final Map.Entry<TaskId, Task> entry :
tasksForLocalState.entrySet()) {
+ if (predicate.test(entry.getValue()) &&
tasksForLocalState.remove(entry.getKey()) != null) {
Review Comment:
Is this on the hot code path? It seems not? -- I understand that you like to
avoid `synchronized` but to me it's also a question about code which is easy to
maintain and robust, and this might be a per-mature optimization?
There is the danger that somebody removes this condition in the future, not
understanding the impact...
If you insist on this, let's at least add a comment why this check is
necessary and should not be removed.
--
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.
To unsubscribe, e-mail: [email protected]
For queries about this service, please contact Infrastructure at:
[email protected]
