Introduce --experimental_parallel_aquery_output.
This flag would enable blaze to process the analysis graph in parallel while
constructing an aquery result, instead of sequentially. The implementation follows a producer-consumer pattern to reduce the impact of the IO bottleneck.
PiperOrigin-RevId: 518804027
Change-Id: I912a0170767c1a3a0184bbd024d48b037ec7de19
diff --git a/src/main/java/com/google/devtools/build/lib/query2/aquery/ActionGraphProtoOutputFormatterCallback.java b/src/main/java/com/google/devtools/build/lib/query2/aquery/ActionGraphProtoOutputFormatterCallback.java
index ad41422..1afdc5c 100644
--- a/src/main/java/com/google/devtools/build/lib/query2/aquery/ActionGraphProtoOutputFormatterCallback.java
+++ b/src/main/java/com/google/devtools/build/lib/query2/aquery/ActionGraphProtoOutputFormatterCallback.java
@@ -13,10 +13,12 @@
// limitations under the License.
package com.google.devtools.build.lib.query2.aquery;
+import com.google.common.collect.ImmutableList;
import com.google.devtools.build.lib.actions.CommandLineExpansionException;
import com.google.devtools.build.lib.analysis.AspectValue;
import com.google.devtools.build.lib.analysis.ConfiguredTargetValue;
import com.google.devtools.build.lib.analysis.actions.TemplateExpansionException;
+import com.google.devtools.build.lib.concurrent.NamedForkJoinPool;
import com.google.devtools.build.lib.events.ExtendedEventHandler;
import com.google.devtools.build.lib.profiler.Profiler;
import com.google.devtools.build.lib.profiler.SilentCloseable;
@@ -24,18 +26,29 @@
import com.google.devtools.build.lib.skyframe.RuleConfiguredTargetValue;
import com.google.devtools.build.lib.skyframe.SkyframeExecutor;
import com.google.devtools.build.lib.skyframe.actiongraph.v2.ActionGraphDump;
+import com.google.devtools.build.lib.skyframe.actiongraph.v2.AqueryConsumingOutputHandler;
import com.google.devtools.build.lib.skyframe.actiongraph.v2.AqueryOutputHandler;
import com.google.devtools.build.lib.skyframe.actiongraph.v2.AqueryOutputHandler.OutputType;
import com.google.devtools.build.lib.skyframe.actiongraph.v2.MonolithicOutputHandler;
+import com.google.devtools.build.lib.skyframe.actiongraph.v2.StreamedConsumingOutputHandler;
import com.google.devtools.build.lib.skyframe.actiongraph.v2.StreamedOutputHandler;
import com.google.protobuf.CodedOutputStream;
import java.io.IOException;
import java.io.OutputStream;
import java.io.PrintStream;
+import java.util.List;
+import java.util.concurrent.Callable;
+import java.util.concurrent.ExecutionException;
+import java.util.concurrent.ForkJoinPool;
+import java.util.concurrent.Future;
+import java.util.concurrent.LinkedBlockingQueue;
/** Default output callback for aquery, prints proto output. */
public class ActionGraphProtoOutputFormatterCallback extends AqueryThreadsafeCallback {
+ // TODO(b/274595070): Clean this up after flag flip.
+ // Arbitrarily chosen. Large enough for good performance, small enough not to cause OOMs.
+ private static final int BLOCKING_QUEUE_SIZE = Runtime.getRuntime().availableProcessors() * 2;
private final OutputType outputType;
private final ActionGraphDump actionGraphDump;
private final AqueryActionFilter actionFilters;
@@ -58,7 +71,8 @@
super(eventHandler, options, out, skyframeExecutor, accessor);
this.outputType = outputType;
this.actionFilters = actionFilters;
- this.aqueryOutputHandler = constructAqueryOutputHandler(outputType, out, printStream);
+ this.aqueryOutputHandler =
+ constructAqueryOutputHandler(outputType, out, printStream, options.parallelAqueryOutput);
this.actionGraphDump =
new ActionGraphDump(
options.includeCommandline,
@@ -73,11 +87,22 @@
public static AqueryOutputHandler constructAqueryOutputHandler(
OutputType outputType, OutputStream out, PrintStream printStream) {
+ return constructAqueryOutputHandler(outputType, out, printStream, /* parallelized= */ false);
+ }
+
+ private static AqueryOutputHandler constructAqueryOutputHandler(
+ OutputType outputType, OutputStream out, PrintStream printStream, boolean parallelized) {
switch (outputType) {
case BINARY:
case TEXT:
- return new StreamedOutputHandler(
- outputType, CodedOutputStream.newInstance(out, OUTPUT_BUFFER_SIZE), printStream);
+ return parallelized
+ ? new StreamedConsumingOutputHandler(
+ outputType,
+ CodedOutputStream.newInstance(out, OUTPUT_BUFFER_SIZE),
+ printStream,
+ new LinkedBlockingQueue<>(BLOCKING_QUEUE_SIZE))
+ : new StreamedOutputHandler(
+ outputType, CodedOutputStream.newInstance(out, OUTPUT_BUFFER_SIZE), printStream);
case JSON:
return new MonolithicOutputHandler(printStream);
}
@@ -91,38 +116,117 @@
}
@Override
+ public void close(boolean failFast) throws IOException {
+ if (!failFast) {
+ try (SilentCloseable c = Profiler.instance().profile("aqueryOutputHandler.close")) {
+ aqueryOutputHandler.close();
+ }
+ }
+ }
+
+ @Override
public void processOutput(Iterable<KeyedConfiguredTargetValue> partialResult)
throws IOException, InterruptedException {
+ if (options.parallelAqueryOutput
+ && aqueryOutputHandler instanceof AqueryConsumingOutputHandler) {
+ processOutputInParallel(partialResult);
+ return;
+ }
+
try (SilentCloseable c = Profiler.instance().profile("process partial result")) {
// Enabling includeParamFiles should enable includeCommandline by default.
options.includeCommandline |= options.includeParamFiles;
for (KeyedConfiguredTargetValue keyedConfiguredTargetValue : partialResult) {
- ConfiguredTargetValue configuredTargetValue =
- keyedConfiguredTargetValue.getConfiguredTargetValue();
- if (!(configuredTargetValue instanceof RuleConfiguredTargetValue)) {
- // We have to include non-rule values in the graph to visit their dependencies, but they
- // don't have any actions to print out.
- continue;
- }
- actionGraphDump.dumpConfiguredTarget((RuleConfiguredTargetValue) configuredTargetValue);
- if (options.useAspects) {
- for (AspectValue aspectValue : accessor.getAspectValues(keyedConfiguredTargetValue)) {
- actionGraphDump.dumpAspect(aspectValue, configuredTargetValue);
- }
- }
+ processSingleEntry(keyedConfiguredTargetValue);
}
} catch (CommandLineExpansionException | TemplateExpansionException e) {
throw new IOException(e.getMessage());
}
}
- @Override
- public void close(boolean failFast) throws IOException {
- if (!failFast) {
- try (SilentCloseable c = Profiler.instance().profile("aqueryOutputHandler.close")) {
- aqueryOutputHandler.close();
+ private void processSingleEntry(KeyedConfiguredTargetValue keyedConfiguredTargetValue)
+ throws CommandLineExpansionException,
+ InterruptedException,
+ IOException,
+ TemplateExpansionException {
+ ConfiguredTargetValue configuredTargetValue =
+ keyedConfiguredTargetValue.getConfiguredTargetValue();
+ if (!(configuredTargetValue instanceof RuleConfiguredTargetValue)) {
+ // We have to include non-rule values in the graph to visit their dependencies, but they
+ // don't have any actions to print out.
+ return;
+ }
+ actionGraphDump.dumpConfiguredTarget((RuleConfiguredTargetValue) configuredTargetValue);
+ if (options.useAspects) {
+ for (AspectValue aspectValue : accessor.getAspectValues(keyedConfiguredTargetValue)) {
+ actionGraphDump.dumpAspect(aspectValue, configuredTargetValue);
}
}
}
+
+ private void processOutputInParallel(Iterable<KeyedConfiguredTargetValue> partialResult)
+ throws IOException, InterruptedException {
+ AqueryConsumingOutputHandler aqueryConsumingOutputHandler =
+ (AqueryConsumingOutputHandler) aqueryOutputHandler;
+ try (SilentCloseable c = Profiler.instance().profile("process partial result")) {
+ // Enabling includeParamFiles should enable includeCommandline by default.
+ options.includeCommandline |= options.includeParamFiles;
+ aqueryConsumingOutputHandler.startConsumer();
+ ForkJoinPool executor =
+ NamedForkJoinPool.newNamedPool("aquery", Runtime.getRuntime().availableProcessors());
+
+ try {
+ List<Future<Void>> futures = executor.invokeAll(toTasks(partialResult));
+ for (Future<Void> future : futures) {
+ future.get();
+ }
+ } catch (ExecutionException e) {
+ Throwable cause = e.getCause();
+ if (cause instanceof CommandLineExpansionException
+ || cause instanceof TemplateExpansionException) {
+ // This is kinda weird, but keeping it in line with the status quo for now.
+ // TODO(b/266179316): Clean this up.
+ throw new IOException(cause.getMessage());
+ }
+ if (cause instanceof IOException) {
+ throw (IOException) cause;
+ }
+ if (cause instanceof InterruptedException) {
+ throw (InterruptedException) cause;
+ }
+ throw new IllegalStateException("Unexpected exception type: ", e);
+ } finally {
+ aqueryConsumingOutputHandler.stopConsumer();
+ executor.shutdown();
+ }
+ }
+ }
+
+ private ImmutableList<AqueryOutputTask> toTasks(Iterable<KeyedConfiguredTargetValue> values) {
+ ImmutableList.Builder<AqueryOutputTask> tasks = ImmutableList.builder();
+ for (KeyedConfiguredTargetValue value : values) {
+ tasks.add(new AqueryOutputTask(value));
+ }
+ return tasks.build();
+ }
+
+ private final class AqueryOutputTask implements Callable<Void> {
+
+ private final KeyedConfiguredTargetValue keyedConfiguredTargetValue;
+
+ AqueryOutputTask(KeyedConfiguredTargetValue keyedConfiguredTargetValue) {
+ this.keyedConfiguredTargetValue = keyedConfiguredTargetValue;
+ }
+
+ @Override
+ public Void call()
+ throws CommandLineExpansionException,
+ TemplateExpansionException,
+ IOException,
+ InterruptedException {
+ processSingleEntry(keyedConfiguredTargetValue);
+ return null;
+ }
+ }
}
diff --git a/src/main/java/com/google/devtools/build/lib/query2/aquery/AqueryOptions.java b/src/main/java/com/google/devtools/build/lib/query2/aquery/AqueryOptions.java
index 0fd4af4..f848580 100644
--- a/src/main/java/com/google/devtools/build/lib/query2/aquery/AqueryOptions.java
+++ b/src/main/java/com/google/devtools/build/lib/query2/aquery/AqueryOptions.java
@@ -89,4 +89,14 @@
+ " output. This does not deduplicate depsets that don't share an immediate parent."
+ " This does not affect the final effective list of input artifacts of the actions.")
public boolean deduplicateDepsets;
+
+ @Option(
+ name = "experimental_parallel_aquery_output",
+ defaultValue = "false",
+ documentationCategory = OptionDocumentationCategory.QUERY,
+ effectTags = {OptionEffectTag.UNKNOWN},
+ help =
+ "Whether aquery proto/textproto output should be written in parallel. No-op for the "
+ + "other output formats.")
+ public boolean parallelAqueryOutput;
}
diff --git a/src/main/java/com/google/devtools/build/lib/skyframe/actiongraph/v2/AqueryConsumingOutputHandler.java b/src/main/java/com/google/devtools/build/lib/skyframe/actiongraph/v2/AqueryConsumingOutputHandler.java
new file mode 100644
index 0000000..44dbfad
--- /dev/null
+++ b/src/main/java/com/google/devtools/build/lib/skyframe/actiongraph/v2/AqueryConsumingOutputHandler.java
@@ -0,0 +1,22 @@
+// Copyright 2023 The Bazel Authors. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+package com.google.devtools.build.lib.skyframe.actiongraph.v2;
+
+/** AqueryOutputHandler that receives and consumes tasks via a work queue. */
+public interface AqueryConsumingOutputHandler extends AqueryOutputHandler {
+
+ void startConsumer();
+
+ void stopConsumer();
+}
diff --git a/src/main/java/com/google/devtools/build/lib/skyframe/actiongraph/v2/BUILD b/src/main/java/com/google/devtools/build/lib/skyframe/actiongraph/v2/BUILD
index 37515ed..e60c0ca 100644
--- a/src/main/java/com/google/devtools/build/lib/skyframe/actiongraph/v2/BUILD
+++ b/src/main/java/com/google/devtools/build/lib/skyframe/actiongraph/v2/BUILD
@@ -35,6 +35,7 @@
"//src/main/java/com/google/devtools/build/lib/vfs:pathfragment",
"//src/main/java/net/starlark/java/eval",
"//src/main/protobuf:analysis_v2_java_proto",
+ "//third_party:auto_value",
"//third_party:guava",
"//third_party:jsr305",
"//third_party/protobuf:protobuf_java",
diff --git a/src/main/java/com/google/devtools/build/lib/skyframe/actiongraph/v2/BaseCache.java b/src/main/java/com/google/devtools/build/lib/skyframe/actiongraph/v2/BaseCache.java
index e4eff0f..5719ce5 100644
--- a/src/main/java/com/google/devtools/build/lib/skyframe/actiongraph/v2/BaseCache.java
+++ b/src/main/java/com/google/devtools/build/lib/skyframe/actiongraph/v2/BaseCache.java
@@ -14,14 +14,14 @@
package com.google.devtools.build.lib.skyframe.actiongraph.v2;
import java.io.IOException;
-import java.util.HashMap;
import java.util.Map;
+import java.util.concurrent.ConcurrentHashMap;
/**
* Basic class to abstract action graph cache functionality.
*/
abstract class BaseCache<K, P> {
- private final Map<K, Integer> cache = new HashMap<>();
+ private final Map<K, Integer> cache = new ConcurrentHashMap<>();
protected final AqueryOutputHandler aqueryOutputHandler;
BaseCache(AqueryOutputHandler aqueryOutputHandler) {
diff --git a/src/main/java/com/google/devtools/build/lib/skyframe/actiongraph/v2/PrintTask.java b/src/main/java/com/google/devtools/build/lib/skyframe/actiongraph/v2/PrintTask.java
new file mode 100644
index 0000000..5f0443f
--- /dev/null
+++ b/src/main/java/com/google/devtools/build/lib/skyframe/actiongraph/v2/PrintTask.java
@@ -0,0 +1,54 @@
+// Copyright 2023 The Bazel Authors. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+package com.google.devtools.build.lib.skyframe.actiongraph.v2;
+
+import com.google.auto.value.AutoValue;
+import com.google.protobuf.Message;
+import javax.annotation.Nullable;
+
+/**
+ * Represent a task to be consumed by a {@link AqueryConsumingOutputHandler}.
+ *
+ * <p>We have separate Proto/TextProto subclasses to reduce some memory waste: we'll never need both
+ * the fieldNumber and the messageLabel in a PrintTask.
+ */
+@SuppressWarnings("InterfaceWithOnlyStatics")
+public interface PrintTask {
+
+ /** A task for the proto format. */
+ @AutoValue
+ abstract class ProtoPrintTask implements PrintTask {
+ @Nullable
+ abstract Message message();
+
+ abstract int fieldNumber();
+
+ public static ProtoPrintTask create(Message message, int fieldNumber) {
+ return new AutoValue_PrintTask_ProtoPrintTask(message, fieldNumber);
+ }
+ }
+
+ /** A task for the textproto format. */
+ @AutoValue
+ abstract class TextProtoPrintTask implements PrintTask {
+ @Nullable
+ abstract Message message();
+
+ abstract String messageLabel();
+
+ public static TextProtoPrintTask create(Message message, String messageLabel) {
+ return new AutoValue_PrintTask_TextProtoPrintTask(message, messageLabel);
+ }
+ }
+}
diff --git a/src/main/java/com/google/devtools/build/lib/skyframe/actiongraph/v2/StreamedConsumingOutputHandler.java b/src/main/java/com/google/devtools/build/lib/skyframe/actiongraph/v2/StreamedConsumingOutputHandler.java
new file mode 100644
index 0000000..bc89b28
--- /dev/null
+++ b/src/main/java/com/google/devtools/build/lib/skyframe/actiongraph/v2/StreamedConsumingOutputHandler.java
@@ -0,0 +1,170 @@
+// Copyright 2023 The Bazel Authors. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+package com.google.devtools.build.lib.skyframe.actiongraph.v2;
+
+import static com.google.devtools.build.lib.skyframe.actiongraph.v2.AqueryOutputHandler.OutputType.BINARY;
+import static com.google.devtools.build.lib.skyframe.actiongraph.v2.AqueryOutputHandler.OutputType.TEXT;
+
+import com.google.common.base.Preconditions;
+import com.google.devtools.build.lib.analysis.AnalysisProtosV2.Action;
+import com.google.devtools.build.lib.analysis.AnalysisProtosV2.ActionGraphContainer;
+import com.google.devtools.build.lib.analysis.AnalysisProtosV2.Artifact;
+import com.google.devtools.build.lib.analysis.AnalysisProtosV2.AspectDescriptor;
+import com.google.devtools.build.lib.analysis.AnalysisProtosV2.Configuration;
+import com.google.devtools.build.lib.analysis.AnalysisProtosV2.DepSetOfFiles;
+import com.google.devtools.build.lib.analysis.AnalysisProtosV2.PathFragment;
+import com.google.devtools.build.lib.analysis.AnalysisProtosV2.RuleClass;
+import com.google.devtools.build.lib.analysis.AnalysisProtosV2.Target;
+import com.google.devtools.build.lib.skyframe.actiongraph.v2.PrintTask.ProtoPrintTask;
+import com.google.devtools.build.lib.skyframe.actiongraph.v2.PrintTask.TextProtoPrintTask;
+import com.google.protobuf.CodedOutputStream;
+import com.google.protobuf.Message;
+import java.io.IOException;
+import java.io.PrintStream;
+import java.util.concurrent.BlockingQueue;
+
+/** Manages the various streamed output channels of aquery. This does not support JSON format. */
+public class StreamedConsumingOutputHandler implements AqueryConsumingOutputHandler {
+
+ public static final PrintTask POISON_PILL = ProtoPrintTask.create(null, 0);
+ private final OutputType outputType;
+ private final CodedOutputStream outputStream;
+ private final PrintStream printStream;
+
+ private final BlockingQueue<PrintTask> queue;
+
+ public StreamedConsumingOutputHandler(
+ OutputType outputType,
+ CodedOutputStream outputStream,
+ PrintStream printStream,
+ BlockingQueue<PrintTask> queue) {
+ this.outputType = outputType;
+ Preconditions.checkArgument(
+ outputType == BINARY || outputType == TEXT,
+ "Only proto and textproto outputs should be streamed.");
+ this.outputStream = outputStream;
+ this.printStream = printStream;
+ this.queue = queue;
+ }
+
+ @Override
+ public void outputArtifact(Artifact message) {
+ addTaskToQueue(message, ActionGraphContainer.ARTIFACTS_FIELD_NUMBER, "artifacts");
+ }
+
+ @Override
+ public void outputAction(Action message) {
+ addTaskToQueue(message, ActionGraphContainer.ACTIONS_FIELD_NUMBER, "actions");
+ }
+
+ @Override
+ public void outputTarget(Target message) {
+ addTaskToQueue(message, ActionGraphContainer.TARGETS_FIELD_NUMBER, "targets");
+ }
+
+ @Override
+ public void outputDepSetOfFiles(DepSetOfFiles message) {
+ addTaskToQueue(message, ActionGraphContainer.DEP_SET_OF_FILES_FIELD_NUMBER, "dep_set_of_files");
+ }
+
+ @Override
+ public void outputConfiguration(Configuration message) {
+ addTaskToQueue(message, ActionGraphContainer.CONFIGURATION_FIELD_NUMBER, "configuration");
+ }
+
+ @Override
+ public void outputAspectDescriptor(AspectDescriptor message) {
+ addTaskToQueue(
+ message, ActionGraphContainer.ASPECT_DESCRIPTORS_FIELD_NUMBER, "aspect_descriptors");
+ }
+
+ @Override
+ public void outputRuleClass(RuleClass message) {
+ addTaskToQueue(message, ActionGraphContainer.RULE_CLASSES_FIELD_NUMBER, "rule_classes");
+ }
+
+ @Override
+ public void outputPathFragment(PathFragment message) {
+ addTaskToQueue(message, ActionGraphContainer.PATH_FRAGMENTS_FIELD_NUMBER, "path_fragments");
+ }
+
+ @Override
+ public void startConsumer() {
+ new Thread(new AqueryOutputTaskConsumer(queue)).start();
+ }
+
+ @Override
+ public void stopConsumer() {
+ queue.add(POISON_PILL);
+ }
+
+ /** Construct the printing task and put it in the queue. */
+ void addTaskToQueue(Message message, int fieldNumber, String messageLabel) {
+ try {
+ queue.put(
+ outputType == BINARY
+ ? ProtoPrintTask.create(message, fieldNumber)
+ : TextProtoPrintTask.create(message, messageLabel));
+ } catch (InterruptedException e) {
+ Thread.currentThread().interrupt();
+ }
+ }
+
+ @Override
+ public void close() throws IOException {
+ outputStream.flush();
+ printStream.flush();
+ }
+
+ private class AqueryOutputTaskConsumer implements Runnable {
+ private final BlockingQueue<PrintTask> queue;
+
+ AqueryOutputTaskConsumer(BlockingQueue<PrintTask> queue) {
+ this.queue = queue;
+ }
+
+ @Override
+ public void run() {
+ try {
+ while (true) {
+ PrintTask nextTask = queue.take();
+
+ if (nextTask.equals(POISON_PILL)) {
+ return;
+ }
+ switch (outputType) {
+ case BINARY:
+ ProtoPrintTask protoPrintTask = (ProtoPrintTask) nextTask;
+ outputStream.writeMessage(protoPrintTask.fieldNumber(), protoPrintTask.message());
+ break;
+ case TEXT:
+ TextProtoPrintTask textProtoPrintTask = (TextProtoPrintTask) nextTask;
+ printStream.print(
+ textProtoPrintTask.messageLabel()
+ + " {\n"
+ + textProtoPrintTask.message()
+ + "}\n");
+ break;
+ default:
+ throw new IllegalStateException("Unknown outputType " + outputType.formatName());
+ }
+ }
+ } catch (InterruptedException e) {
+ Thread.currentThread().interrupt();
+ } catch (IOException e) {
+ throw new IllegalStateException("Unexpected exception: ", e);
+ }
+ }
+ }
+}
diff --git a/src/main/java/com/google/devtools/build/lib/skyframe/actiongraph/v2/StreamedOutputHandler.java b/src/main/java/com/google/devtools/build/lib/skyframe/actiongraph/v2/StreamedOutputHandler.java
index 51c537e..513de4f 100644
--- a/src/main/java/com/google/devtools/build/lib/skyframe/actiongraph/v2/StreamedOutputHandler.java
+++ b/src/main/java/com/google/devtools/build/lib/skyframe/actiongraph/v2/StreamedOutputHandler.java
@@ -31,7 +31,10 @@
import java.io.IOException;
import java.io.PrintStream;
-/** Manages the various streamed output channels of aquery. This does not support JSON format. */
+/**
+ * Manages the various streamed output channels of aquery. This does not support JSON format.
+ * TODO(b/274595070) Remove this class after the flag flip.
+ */
public class StreamedOutputHandler implements AqueryOutputHandler {
private final OutputType outputType;
private final CodedOutputStream outputStream;
