Copilot commented on code in PR #16409:
URL: https://github.com/apache/pinot/pull/16409#discussion_r2225103604
##########
pinot-spi/src/main/java/org/apache/pinot/spi/executor/ThrottleOnCriticalHeapUsageExecutor.java:
##########
@@ -18,46 +18,432 @@
*/
package org.apache.pinot.spi.executor;
+import java.util.concurrent.BlockingQueue;
import java.util.concurrent.Callable;
import java.util.concurrent.ExecutorService;
+import java.util.concurrent.Executors;
+import java.util.concurrent.LinkedBlockingQueue;
+import java.util.concurrent.ScheduledExecutorService;
+import java.util.concurrent.TimeUnit;
+import java.util.concurrent.atomic.AtomicBoolean;
+import java.util.concurrent.atomic.AtomicInteger;
import org.apache.pinot.spi.accounting.ThreadResourceUsageAccountant;
import org.apache.pinot.spi.exception.QueryErrorCode;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
/**
- * An Executor that throttles task submission when the heap usage is critical.
+ * An Executor that queues tasks when the heap usage is critical instead of
rejecting them.
* Heap Usage level is obtained from {@link
ThreadResourceUsageAccountant#throttleQuerySubmission()}.
+ *
+ * Features:
+ * - Tasks are queued when heap usage is critical
+ * - Queued tasks are processed when heap usage drops below critical level
+ * - Configurable queue size and timeout
+ * - Background monitoring of heap usage to process queued tasks
*/
public class ThrottleOnCriticalHeapUsageExecutor extends
DecoratorExecutorService {
- ThreadResourceUsageAccountant _threadResourceUsageAccountant;
+ private static final Logger LOGGER =
LoggerFactory.getLogger(ThrottleOnCriticalHeapUsageExecutor.class);
+
+ // Default configuration values
+ private static final int DEFAULT_QUEUE_SIZE = 1000;
+ private static final long DEFAULT_QUEUE_TIMEOUT_MS = 30000; // 30 seconds
+ private static final long DEFAULT_MONITOR_INTERVAL_MS = 1000; // 1 second
+
+ private final ThreadResourceUsageAccountant _threadResourceUsageAccountant;
+ private final BlockingQueue<QueuedTask> _taskQueue;
+ private final int _maxQueueSize;
+ private final long _queueTimeoutMs;
+ private final ScheduledExecutorService _monitorExecutor;
+ private final AtomicBoolean _isShutdown = new AtomicBoolean(false);
+ private final AtomicInteger _queuedTaskCount = new AtomicInteger(0);
+ private final AtomicInteger _processedTaskCount = new AtomicInteger(0);
+ private final AtomicInteger _timedOutTaskCount = new AtomicInteger(0);
public ThrottleOnCriticalHeapUsageExecutor(ExecutorService executorService,
ThreadResourceUsageAccountant threadResourceUsageAccountant) {
+ this(executorService, threadResourceUsageAccountant, DEFAULT_QUEUE_SIZE,
+ DEFAULT_QUEUE_TIMEOUT_MS, DEFAULT_MONITOR_INTERVAL_MS);
+ }
+
+ public ThrottleOnCriticalHeapUsageExecutor(ExecutorService executorService,
+ ThreadResourceUsageAccountant threadResourceUsageAccountant,
+ int maxQueueSize, long queueTimeoutMs, long monitorIntervalMs) {
super(executorService);
_threadResourceUsageAccountant = threadResourceUsageAccountant;
+ _maxQueueSize = maxQueueSize;
+ _queueTimeoutMs = queueTimeoutMs;
+ _taskQueue = new LinkedBlockingQueue<>(maxQueueSize);
+
+ // Create a single-threaded scheduler for monitoring heap usage
+ _monitorExecutor = Executors.newSingleThreadScheduledExecutor(r -> {
+ Thread t = new Thread(r, "throttle-heap-monitor");
+ t.setDaemon(true);
+ return t;
+ });
+
+ // Start the monitoring task
+ _monitorExecutor.scheduleWithFixedDelay(this::processQueuedTasks,
+ monitorIntervalMs, monitorIntervalMs, TimeUnit.MILLISECONDS);
+
+ LOGGER.info(
+ "ThrottleOnCriticalHeapUsageExecutor initialized with queue size: {},
timeout: {}ms, monitor interval: {}ms",
+ maxQueueSize, queueTimeoutMs, monitorIntervalMs);
}
protected void checkTaskAllowed() {
- if (_threadResourceUsageAccountant.throttleQuerySubmission()) {
- throw QueryErrorCode.SERVER_RESOURCE_LIMIT_EXCEEDED.asException("Tasks
throttled due to high heap usage.");
+ }
+
+ /**
+ * Check if a task should be queued due to critical heap usage
+ * @return true if the task should be queued, false if it can be executed
immediately
+ */
+ protected boolean shouldQueueTask() {
+ return _threadResourceUsageAccountant.throttleQuerySubmission();
+ }
+
+ /**
+ * Process queued tasks when heap usage is below critical level
+ */
+ private void processQueuedTasks() {
+ if (_isShutdown.get()) {
+ return;
+ }
+
+ try {
+ // Process tasks while heap usage is not critical and queue is not empty
+ while (!shouldQueueTask() && !_taskQueue.isEmpty()) {
+ QueuedTask queuedTask = _taskQueue.poll();
+ if (queuedTask != null) {
+ long queueTime = System.currentTimeMillis() -
queuedTask.getQueueTime();
+
+ if (queueTime > _queueTimeoutMs) {
+ // Task has timed out in queue
+ queuedTask.timeout();
+ _timedOutTaskCount.incrementAndGet();
+ LOGGER.warn("Task timed out after {}ms in queue", queueTime);
+ } else {
+ // Submit the task for execution
+ try {
+ queuedTask.execute();
+ _processedTaskCount.incrementAndGet();
+ LOGGER.debug("Processed queued task after {}ms in queue",
queueTime);
+ } catch (Exception e) {
+ LOGGER.error("Error executing queued task", e);
+ queuedTask.fail(e);
+ }
+ }
+ }
+ }
+ } catch (Exception e) {
+ LOGGER.error("Error in processQueuedTasks", e);
}
}
@Override
protected <T> Callable<T> decorate(Callable<T> task) {
- checkTaskAllowed();
return () -> {
- checkTaskAllowed();
- return task.call();
+ if (shouldQueueTask()) {
+ // Queue the task if heap usage is critical
+ return queueCallableTask(task);
+ } else {
+ // Execute immediately if heap usage is normal
+ return task.call();
+ }
};
}
@Override
protected Runnable decorate(Runnable task) {
- checkTaskAllowed();
return () -> {
- checkTaskAllowed();
- task.run();
+ if (shouldQueueTask()) {
+ // Queue the task if heap usage is critical
+ queueRunnableTask(task);
+ } else {
+ // Execute immediately if heap usage is normal
+ task.run();
+ }
};
}
+
+ /**
+ * Queue a callable task and wait for its execution
+ */
+ private <T> T queueCallableTask(Callable<T> task)
+ throws Exception {
+ QueuedCallableTask<T> queuedTask = new QueuedCallableTask<>(task);
+
+ if (!_taskQueue.offer(queuedTask)) {
+ // Queue is full
+ throw QueryErrorCode.SERVER_RESOURCE_LIMIT_EXCEEDED.asException(
+ "Task queue is full (size: " + _maxQueueSize + ") due to high heap
usage.");
+ }
+
+ _queuedTaskCount.incrementAndGet();
+ LOGGER.debug("Queued callable task, queue size: {}", _taskQueue.size());
+
+ // Wait for the task to complete or timeout
+ return queuedTask.get(_queueTimeoutMs, TimeUnit.MILLISECONDS);
+ }
+
+ /**
+ * Queue a runnable task and wait for its execution
+ */
+ private void queueRunnableTask(Runnable task) {
+ QueuedRunnableTask queuedTask = new QueuedRunnableTask(task);
+
+ if (!_taskQueue.offer(queuedTask)) {
+ // Queue is full
+ throw QueryErrorCode.SERVER_RESOURCE_LIMIT_EXCEEDED.asException(
+ "Task queue is full (size: " + _maxQueueSize + ") due to high heap
usage.");
+ }
+
+ _queuedTaskCount.incrementAndGet();
+ LOGGER.debug("Queued runnable task, queue size: {}", _taskQueue.size());
+
+ try {
+ // Wait for the task to complete or timeout
+ queuedTask.get(_queueTimeoutMs, TimeUnit.MILLISECONDS);
+ } catch (Exception e) {
+ if (e.getCause() instanceof RuntimeException) {
+ throw (RuntimeException) e.getCause();
+ } else {
+ throw new RuntimeException("Error executing queued task", e);
+ }
+ }
+ }
+
+ @Override
+ public void shutdown() {
+ _isShutdown.set(true);
+ _monitorExecutor.shutdown();
Review Comment:
The shutdown method should call _monitorExecutor.shutdownNow() instead of
shutdown() to ensure the background monitoring thread is interrupted
immediately, preventing potential delays during application shutdown.
```suggestion
_monitorExecutor.shutdownNow();
```
##########
pinot-spi/src/main/java/org/apache/pinot/spi/executor/ThrottleOnCriticalHeapUsageExecutor.java:
##########
@@ -18,46 +18,432 @@
*/
package org.apache.pinot.spi.executor;
+import java.util.concurrent.BlockingQueue;
import java.util.concurrent.Callable;
import java.util.concurrent.ExecutorService;
+import java.util.concurrent.Executors;
+import java.util.concurrent.LinkedBlockingQueue;
+import java.util.concurrent.ScheduledExecutorService;
+import java.util.concurrent.TimeUnit;
+import java.util.concurrent.atomic.AtomicBoolean;
+import java.util.concurrent.atomic.AtomicInteger;
import org.apache.pinot.spi.accounting.ThreadResourceUsageAccountant;
import org.apache.pinot.spi.exception.QueryErrorCode;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
/**
- * An Executor that throttles task submission when the heap usage is critical.
+ * An Executor that queues tasks when the heap usage is critical instead of
rejecting them.
* Heap Usage level is obtained from {@link
ThreadResourceUsageAccountant#throttleQuerySubmission()}.
+ *
+ * Features:
+ * - Tasks are queued when heap usage is critical
+ * - Queued tasks are processed when heap usage drops below critical level
+ * - Configurable queue size and timeout
+ * - Background monitoring of heap usage to process queued tasks
*/
public class ThrottleOnCriticalHeapUsageExecutor extends
DecoratorExecutorService {
- ThreadResourceUsageAccountant _threadResourceUsageAccountant;
+ private static final Logger LOGGER =
LoggerFactory.getLogger(ThrottleOnCriticalHeapUsageExecutor.class);
+
+ // Default configuration values
+ private static final int DEFAULT_QUEUE_SIZE = 1000;
+ private static final long DEFAULT_QUEUE_TIMEOUT_MS = 30000; // 30 seconds
+ private static final long DEFAULT_MONITOR_INTERVAL_MS = 1000; // 1 second
+
+ private final ThreadResourceUsageAccountant _threadResourceUsageAccountant;
+ private final BlockingQueue<QueuedTask> _taskQueue;
+ private final int _maxQueueSize;
+ private final long _queueTimeoutMs;
+ private final ScheduledExecutorService _monitorExecutor;
+ private final AtomicBoolean _isShutdown = new AtomicBoolean(false);
+ private final AtomicInteger _queuedTaskCount = new AtomicInteger(0);
+ private final AtomicInteger _processedTaskCount = new AtomicInteger(0);
+ private final AtomicInteger _timedOutTaskCount = new AtomicInteger(0);
public ThrottleOnCriticalHeapUsageExecutor(ExecutorService executorService,
ThreadResourceUsageAccountant threadResourceUsageAccountant) {
+ this(executorService, threadResourceUsageAccountant, DEFAULT_QUEUE_SIZE,
+ DEFAULT_QUEUE_TIMEOUT_MS, DEFAULT_MONITOR_INTERVAL_MS);
+ }
+
+ public ThrottleOnCriticalHeapUsageExecutor(ExecutorService executorService,
+ ThreadResourceUsageAccountant threadResourceUsageAccountant,
+ int maxQueueSize, long queueTimeoutMs, long monitorIntervalMs) {
super(executorService);
_threadResourceUsageAccountant = threadResourceUsageAccountant;
+ _maxQueueSize = maxQueueSize;
+ _queueTimeoutMs = queueTimeoutMs;
+ _taskQueue = new LinkedBlockingQueue<>(maxQueueSize);
+
+ // Create a single-threaded scheduler for monitoring heap usage
+ _monitorExecutor = Executors.newSingleThreadScheduledExecutor(r -> {
+ Thread t = new Thread(r, "throttle-heap-monitor");
+ t.setDaemon(true);
+ return t;
+ });
+
+ // Start the monitoring task
+ _monitorExecutor.scheduleWithFixedDelay(this::processQueuedTasks,
+ monitorIntervalMs, monitorIntervalMs, TimeUnit.MILLISECONDS);
+
+ LOGGER.info(
+ "ThrottleOnCriticalHeapUsageExecutor initialized with queue size: {},
timeout: {}ms, monitor interval: {}ms",
+ maxQueueSize, queueTimeoutMs, monitorIntervalMs);
}
protected void checkTaskAllowed() {
- if (_threadResourceUsageAccountant.throttleQuerySubmission()) {
- throw QueryErrorCode.SERVER_RESOURCE_LIMIT_EXCEEDED.asException("Tasks
throttled due to high heap usage.");
+ }
+
+ /**
+ * Check if a task should be queued due to critical heap usage
+ * @return true if the task should be queued, false if it can be executed
immediately
+ */
+ protected boolean shouldQueueTask() {
+ return _threadResourceUsageAccountant.throttleQuerySubmission();
+ }
+
+ /**
+ * Process queued tasks when heap usage is below critical level
+ */
+ private void processQueuedTasks() {
+ if (_isShutdown.get()) {
+ return;
+ }
+
+ try {
+ // Process tasks while heap usage is not critical and queue is not empty
+ while (!shouldQueueTask() && !_taskQueue.isEmpty()) {
+ QueuedTask queuedTask = _taskQueue.poll();
+ if (queuedTask != null) {
+ long queueTime = System.currentTimeMillis() -
queuedTask.getQueueTime();
+
+ if (queueTime > _queueTimeoutMs) {
+ // Task has timed out in queue
+ queuedTask.timeout();
+ _timedOutTaskCount.incrementAndGet();
+ LOGGER.warn("Task timed out after {}ms in queue", queueTime);
+ } else {
+ // Submit the task for execution
+ try {
+ queuedTask.execute();
+ _processedTaskCount.incrementAndGet();
+ LOGGER.debug("Processed queued task after {}ms in queue",
queueTime);
+ } catch (Exception e) {
+ LOGGER.error("Error executing queued task", e);
+ queuedTask.fail(e);
+ }
+ }
+ }
+ }
+ } catch (Exception e) {
+ LOGGER.error("Error in processQueuedTasks", e);
}
}
@Override
protected <T> Callable<T> decorate(Callable<T> task) {
- checkTaskAllowed();
return () -> {
- checkTaskAllowed();
- return task.call();
+ if (shouldQueueTask()) {
+ // Queue the task if heap usage is critical
+ return queueCallableTask(task);
+ } else {
+ // Execute immediately if heap usage is normal
+ return task.call();
+ }
};
}
@Override
protected Runnable decorate(Runnable task) {
- checkTaskAllowed();
return () -> {
- checkTaskAllowed();
- task.run();
+ if (shouldQueueTask()) {
+ // Queue the task if heap usage is critical
+ queueRunnableTask(task);
+ } else {
+ // Execute immediately if heap usage is normal
+ task.run();
+ }
};
}
+
+ /**
+ * Queue a callable task and wait for its execution
+ */
+ private <T> T queueCallableTask(Callable<T> task)
+ throws Exception {
+ QueuedCallableTask<T> queuedTask = new QueuedCallableTask<>(task);
+
+ if (!_taskQueue.offer(queuedTask)) {
+ // Queue is full
+ throw QueryErrorCode.SERVER_RESOURCE_LIMIT_EXCEEDED.asException(
+ "Task queue is full (size: " + _maxQueueSize + ") due to high heap
usage.");
+ }
+
+ _queuedTaskCount.incrementAndGet();
+ LOGGER.debug("Queued callable task, queue size: {}", _taskQueue.size());
+
+ // Wait for the task to complete or timeout
+ return queuedTask.get(_queueTimeoutMs, TimeUnit.MILLISECONDS);
+ }
+
+ /**
+ * Queue a runnable task and wait for its execution
+ */
+ private void queueRunnableTask(Runnable task) {
+ QueuedRunnableTask queuedTask = new QueuedRunnableTask(task);
+
+ if (!_taskQueue.offer(queuedTask)) {
+ // Queue is full
+ throw QueryErrorCode.SERVER_RESOURCE_LIMIT_EXCEEDED.asException(
+ "Task queue is full (size: " + _maxQueueSize + ") due to high heap
usage.");
+ }
+
+ _queuedTaskCount.incrementAndGet();
+ LOGGER.debug("Queued runnable task, queue size: {}", _taskQueue.size());
+
+ try {
+ // Wait for the task to complete or timeout
+ queuedTask.get(_queueTimeoutMs, TimeUnit.MILLISECONDS);
+ } catch (Exception e) {
+ if (e.getCause() instanceof RuntimeException) {
+ throw (RuntimeException) e.getCause();
+ } else {
+ throw new RuntimeException("Error executing queued task", e);
+ }
+ }
+ }
+
+ @Override
+ public void shutdown() {
+ _isShutdown.set(true);
+ _monitorExecutor.shutdown();
+
+ // Process any remaining tasks in the queue
+ while (!_taskQueue.isEmpty()) {
+ QueuedTask task = _taskQueue.poll();
+ if (task != null) {
+ task.timeout();
Review Comment:
Processing remaining tasks during shutdown by calling task.timeout() may
cause unexpected behavior for callers still waiting on these tasks. Consider
using a more graceful approach like setting a shutdown flag and allowing the
monitor thread to complete current processing before terminating.
```suggestion
// Allow the monitor thread to complete current processing
try {
if (!_monitorExecutor.awaitTermination(30, TimeUnit.SECONDS)) {
LOGGER.warn("Monitor executor did not terminate within the timeout
period.");
}
} catch (InterruptedException e) {
LOGGER.warn("Interrupted while waiting for monitor executor to
terminate.", e);
Thread.currentThread().interrupt();
}
// Process any remaining tasks in the queue
while (!_taskQueue.isEmpty()) {
QueuedTask task = _taskQueue.poll();
if (task != null) {
try {
task.run(); // Attempt to execute the task
_processedTaskCount.incrementAndGet();
} catch (Exception e) {
LOGGER.error("Error executing remaining task during shutdown", e);
_timedOutTaskCount.incrementAndGet();
}
```
##########
pinot-spi/src/main/java/org/apache/pinot/spi/executor/ThrottleOnCriticalHeapUsageExecutor.java:
##########
@@ -18,46 +18,432 @@
*/
package org.apache.pinot.spi.executor;
+import java.util.concurrent.BlockingQueue;
import java.util.concurrent.Callable;
import java.util.concurrent.ExecutorService;
+import java.util.concurrent.Executors;
+import java.util.concurrent.LinkedBlockingQueue;
+import java.util.concurrent.ScheduledExecutorService;
+import java.util.concurrent.TimeUnit;
+import java.util.concurrent.atomic.AtomicBoolean;
+import java.util.concurrent.atomic.AtomicInteger;
import org.apache.pinot.spi.accounting.ThreadResourceUsageAccountant;
import org.apache.pinot.spi.exception.QueryErrorCode;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
/**
- * An Executor that throttles task submission when the heap usage is critical.
+ * An Executor that queues tasks when the heap usage is critical instead of
rejecting them.
* Heap Usage level is obtained from {@link
ThreadResourceUsageAccountant#throttleQuerySubmission()}.
+ *
+ * Features:
+ * - Tasks are queued when heap usage is critical
+ * - Queued tasks are processed when heap usage drops below critical level
+ * - Configurable queue size and timeout
+ * - Background monitoring of heap usage to process queued tasks
*/
public class ThrottleOnCriticalHeapUsageExecutor extends
DecoratorExecutorService {
- ThreadResourceUsageAccountant _threadResourceUsageAccountant;
+ private static final Logger LOGGER =
LoggerFactory.getLogger(ThrottleOnCriticalHeapUsageExecutor.class);
+
+ // Default configuration values
+ private static final int DEFAULT_QUEUE_SIZE = 1000;
+ private static final long DEFAULT_QUEUE_TIMEOUT_MS = 30000; // 30 seconds
+ private static final long DEFAULT_MONITOR_INTERVAL_MS = 1000; // 1 second
+
+ private final ThreadResourceUsageAccountant _threadResourceUsageAccountant;
+ private final BlockingQueue<QueuedTask> _taskQueue;
+ private final int _maxQueueSize;
+ private final long _queueTimeoutMs;
+ private final ScheduledExecutorService _monitorExecutor;
+ private final AtomicBoolean _isShutdown = new AtomicBoolean(false);
+ private final AtomicInteger _queuedTaskCount = new AtomicInteger(0);
+ private final AtomicInteger _processedTaskCount = new AtomicInteger(0);
+ private final AtomicInteger _timedOutTaskCount = new AtomicInteger(0);
public ThrottleOnCriticalHeapUsageExecutor(ExecutorService executorService,
ThreadResourceUsageAccountant threadResourceUsageAccountant) {
+ this(executorService, threadResourceUsageAccountant, DEFAULT_QUEUE_SIZE,
+ DEFAULT_QUEUE_TIMEOUT_MS, DEFAULT_MONITOR_INTERVAL_MS);
+ }
+
+ public ThrottleOnCriticalHeapUsageExecutor(ExecutorService executorService,
+ ThreadResourceUsageAccountant threadResourceUsageAccountant,
+ int maxQueueSize, long queueTimeoutMs, long monitorIntervalMs) {
super(executorService);
_threadResourceUsageAccountant = threadResourceUsageAccountant;
+ _maxQueueSize = maxQueueSize;
+ _queueTimeoutMs = queueTimeoutMs;
+ _taskQueue = new LinkedBlockingQueue<>(maxQueueSize);
+
+ // Create a single-threaded scheduler for monitoring heap usage
+ _monitorExecutor = Executors.newSingleThreadScheduledExecutor(r -> {
+ Thread t = new Thread(r, "throttle-heap-monitor");
+ t.setDaemon(true);
+ return t;
+ });
+
+ // Start the monitoring task
+ _monitorExecutor.scheduleWithFixedDelay(this::processQueuedTasks,
+ monitorIntervalMs, monitorIntervalMs, TimeUnit.MILLISECONDS);
+
+ LOGGER.info(
+ "ThrottleOnCriticalHeapUsageExecutor initialized with queue size: {},
timeout: {}ms, monitor interval: {}ms",
+ maxQueueSize, queueTimeoutMs, monitorIntervalMs);
}
protected void checkTaskAllowed() {
- if (_threadResourceUsageAccountant.throttleQuerySubmission()) {
- throw QueryErrorCode.SERVER_RESOURCE_LIMIT_EXCEEDED.asException("Tasks
throttled due to high heap usage.");
+ }
+
+ /**
+ * Check if a task should be queued due to critical heap usage
+ * @return true if the task should be queued, false if it can be executed
immediately
+ */
+ protected boolean shouldQueueTask() {
+ return _threadResourceUsageAccountant.throttleQuerySubmission();
+ }
+
+ /**
+ * Process queued tasks when heap usage is below critical level
+ */
+ private void processQueuedTasks() {
+ if (_isShutdown.get()) {
+ return;
+ }
+
+ try {
+ // Process tasks while heap usage is not critical and queue is not empty
+ while (!shouldQueueTask() && !_taskQueue.isEmpty()) {
+ QueuedTask queuedTask = _taskQueue.poll();
+ if (queuedTask != null) {
+ long queueTime = System.currentTimeMillis() -
queuedTask.getQueueTime();
+
+ if (queueTime > _queueTimeoutMs) {
+ // Task has timed out in queue
+ queuedTask.timeout();
+ _timedOutTaskCount.incrementAndGet();
+ LOGGER.warn("Task timed out after {}ms in queue", queueTime);
+ } else {
+ // Submit the task for execution
+ try {
+ queuedTask.execute();
+ _processedTaskCount.incrementAndGet();
+ LOGGER.debug("Processed queued task after {}ms in queue",
queueTime);
+ } catch (Exception e) {
+ LOGGER.error("Error executing queued task", e);
+ queuedTask.fail(e);
+ }
+ }
+ }
+ }
+ } catch (Exception e) {
+ LOGGER.error("Error in processQueuedTasks", e);
}
}
@Override
protected <T> Callable<T> decorate(Callable<T> task) {
- checkTaskAllowed();
return () -> {
- checkTaskAllowed();
- return task.call();
+ if (shouldQueueTask()) {
+ // Queue the task if heap usage is critical
+ return queueCallableTask(task);
+ } else {
+ // Execute immediately if heap usage is normal
+ return task.call();
+ }
};
}
@Override
protected Runnable decorate(Runnable task) {
- checkTaskAllowed();
return () -> {
- checkTaskAllowed();
- task.run();
+ if (shouldQueueTask()) {
+ // Queue the task if heap usage is critical
+ queueRunnableTask(task);
+ } else {
+ // Execute immediately if heap usage is normal
+ task.run();
+ }
};
}
+
+ /**
+ * Queue a callable task and wait for its execution
+ */
+ private <T> T queueCallableTask(Callable<T> task)
+ throws Exception {
+ QueuedCallableTask<T> queuedTask = new QueuedCallableTask<>(task);
+
+ if (!_taskQueue.offer(queuedTask)) {
+ // Queue is full
+ throw QueryErrorCode.SERVER_RESOURCE_LIMIT_EXCEEDED.asException(
+ "Task queue is full (size: " + _maxQueueSize + ") due to high heap
usage.");
+ }
+
+ _queuedTaskCount.incrementAndGet();
+ LOGGER.debug("Queued callable task, queue size: {}", _taskQueue.size());
+
+ // Wait for the task to complete or timeout
+ return queuedTask.get(_queueTimeoutMs, TimeUnit.MILLISECONDS);
+ }
+
+ /**
+ * Queue a runnable task and wait for its execution
+ */
+ private void queueRunnableTask(Runnable task) {
+ QueuedRunnableTask queuedTask = new QueuedRunnableTask(task);
+
+ if (!_taskQueue.offer(queuedTask)) {
+ // Queue is full
+ throw QueryErrorCode.SERVER_RESOURCE_LIMIT_EXCEEDED.asException(
+ "Task queue is full (size: " + _maxQueueSize + ") due to high heap
usage.");
+ }
+
+ _queuedTaskCount.incrementAndGet();
+ LOGGER.debug("Queued runnable task, queue size: {}", _taskQueue.size());
+
+ try {
+ // Wait for the task to complete or timeout
+ queuedTask.get(_queueTimeoutMs, TimeUnit.MILLISECONDS);
+ } catch (Exception e) {
+ if (e.getCause() instanceof RuntimeException) {
+ throw (RuntimeException) e.getCause();
+ } else {
+ throw new RuntimeException("Error executing queued task", e);
+ }
+ }
+ }
+
+ @Override
+ public void shutdown() {
+ _isShutdown.set(true);
+ _monitorExecutor.shutdown();
+
+ // Process any remaining tasks in the queue
+ while (!_taskQueue.isEmpty()) {
+ QueuedTask task = _taskQueue.poll();
+ if (task != null) {
+ task.timeout();
+ }
+ }
+
+ super.shutdown();
+
+ LOGGER.info("ThrottleOnCriticalHeapUsageExecutor shutdown. Stats - Queued:
{}, Processed: {}, Timed out: {}",
+ _queuedTaskCount.get(), _processedTaskCount.get(),
_timedOutTaskCount.get());
+ }
+
+ /**
+ * Get current queue size
+ */
+ public int getQueueSize() {
+ return _taskQueue.size();
+ }
+
+ /**
+ * Get total number of tasks queued
+ */
+ public int getQueuedTaskCount() {
+ return _queuedTaskCount.get();
+ }
+
+ /**
+ * Get total number of tasks processed from queue
+ */
+ public int getProcessedTaskCount() {
+ return _processedTaskCount.get();
+ }
+
+ /**
+ * Get total number of tasks that timed out in queue
+ */
+ public int getTimedOutTaskCount() {
+ return _timedOutTaskCount.get();
+ }
+
+ /**
+ * Base class for queued tasks
Review Comment:
The QueuedTask abstract class and its implementations (QueuedCallableTask,
QueuedRunnableTask) lack class-level documentation explaining their purpose,
lifecycle, and thread-safety guarantees, which is important for understanding
the complex synchronization logic.
```suggestion
* Base class for queued tasks.
*
* <p>The {@code QueuedTask} class represents a task that can be queued
for execution when the system is under
* critical heap usage. It provides a common interface for handling task
execution, timeouts, and failures.</p>
*
* <p>Lifecycle:
* <ul>
* <li>Tasks are created and added to the queue when heap usage is
critical.</li>
* <li>When heap usage drops below the critical level, tasks are
dequeued and executed.</li>
* <li>If a task remains in the queue beyond a configured timeout, the
{@code timeout()} method is invoked.</li>
* <li>If an exception occurs during execution, the {@code
fail(Exception e)} method is invoked.</li>
* </ul>
* </p>
*
* <p>Thread-safety:
* <ul>
* <li>Instances of {@code QueuedTask} are not inherently thread-safe
and should be accessed in a thread-safe
* manner by the enclosing executor.</li>
* <li>The enclosing {@code ThrottleOnCriticalHeapUsageExecutor} ensures
proper synchronization when accessing
* and modifying the queue.</li>
* </ul>
* </p>
```
##########
pinot-spi/src/main/java/org/apache/pinot/spi/executor/ThrottleOnCriticalHeapUsageExecutor.java:
##########
@@ -18,46 +18,432 @@
*/
package org.apache.pinot.spi.executor;
+import java.util.concurrent.BlockingQueue;
import java.util.concurrent.Callable;
import java.util.concurrent.ExecutorService;
+import java.util.concurrent.Executors;
+import java.util.concurrent.LinkedBlockingQueue;
+import java.util.concurrent.ScheduledExecutorService;
+import java.util.concurrent.TimeUnit;
+import java.util.concurrent.atomic.AtomicBoolean;
+import java.util.concurrent.atomic.AtomicInteger;
import org.apache.pinot.spi.accounting.ThreadResourceUsageAccountant;
import org.apache.pinot.spi.exception.QueryErrorCode;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
/**
- * An Executor that throttles task submission when the heap usage is critical.
+ * An Executor that queues tasks when the heap usage is critical instead of
rejecting them.
* Heap Usage level is obtained from {@link
ThreadResourceUsageAccountant#throttleQuerySubmission()}.
+ *
+ * Features:
+ * - Tasks are queued when heap usage is critical
+ * - Queued tasks are processed when heap usage drops below critical level
+ * - Configurable queue size and timeout
+ * - Background monitoring of heap usage to process queued tasks
*/
public class ThrottleOnCriticalHeapUsageExecutor extends
DecoratorExecutorService {
- ThreadResourceUsageAccountant _threadResourceUsageAccountant;
+ private static final Logger LOGGER =
LoggerFactory.getLogger(ThrottleOnCriticalHeapUsageExecutor.class);
+
+ // Default configuration values
+ private static final int DEFAULT_QUEUE_SIZE = 1000;
+ private static final long DEFAULT_QUEUE_TIMEOUT_MS = 30000; // 30 seconds
+ private static final long DEFAULT_MONITOR_INTERVAL_MS = 1000; // 1 second
+
+ private final ThreadResourceUsageAccountant _threadResourceUsageAccountant;
+ private final BlockingQueue<QueuedTask> _taskQueue;
+ private final int _maxQueueSize;
+ private final long _queueTimeoutMs;
+ private final ScheduledExecutorService _monitorExecutor;
+ private final AtomicBoolean _isShutdown = new AtomicBoolean(false);
+ private final AtomicInteger _queuedTaskCount = new AtomicInteger(0);
+ private final AtomicInteger _processedTaskCount = new AtomicInteger(0);
+ private final AtomicInteger _timedOutTaskCount = new AtomicInteger(0);
public ThrottleOnCriticalHeapUsageExecutor(ExecutorService executorService,
ThreadResourceUsageAccountant threadResourceUsageAccountant) {
+ this(executorService, threadResourceUsageAccountant, DEFAULT_QUEUE_SIZE,
+ DEFAULT_QUEUE_TIMEOUT_MS, DEFAULT_MONITOR_INTERVAL_MS);
+ }
+
+ public ThrottleOnCriticalHeapUsageExecutor(ExecutorService executorService,
+ ThreadResourceUsageAccountant threadResourceUsageAccountant,
+ int maxQueueSize, long queueTimeoutMs, long monitorIntervalMs) {
super(executorService);
_threadResourceUsageAccountant = threadResourceUsageAccountant;
+ _maxQueueSize = maxQueueSize;
+ _queueTimeoutMs = queueTimeoutMs;
+ _taskQueue = new LinkedBlockingQueue<>(maxQueueSize);
+
+ // Create a single-threaded scheduler for monitoring heap usage
+ _monitorExecutor = Executors.newSingleThreadScheduledExecutor(r -> {
+ Thread t = new Thread(r, "throttle-heap-monitor");
+ t.setDaemon(true);
+ return t;
+ });
+
+ // Start the monitoring task
+ _monitorExecutor.scheduleWithFixedDelay(this::processQueuedTasks,
+ monitorIntervalMs, monitorIntervalMs, TimeUnit.MILLISECONDS);
+
+ LOGGER.info(
+ "ThrottleOnCriticalHeapUsageExecutor initialized with queue size: {},
timeout: {}ms, monitor interval: {}ms",
+ maxQueueSize, queueTimeoutMs, monitorIntervalMs);
}
Review Comment:
The method checkTaskAllowed() is now empty but still exists. Since the
functionality has moved to shouldQueueTask(), this method should either be
removed or documented as intentionally empty for backward compatibility.
```suggestion
/**
* This method is intentionally left empty for backward compatibility.
* The functionality has been moved to {@link #shouldQueueTask()}.
*/
```
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