Increased StandardMethodCodec's WriteBuffer start capacity (#101860)

* Added standard method codec benchmark

* increased writebuffer start size

* added const

dev/benchmarks/microbenchmarks/lib/foundation/standard_method_codec_bench.dart

+// Copyright 2014 The Flutter Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+import 'package:flutter/services.dart';
+
+import '../common.dart';
+
+const int _kNumIterations = 100000;
+
+void main() {
+  assert(false,
+      "Don't run benchmarks in checked mode! Use 'flutter run --release'.");
+  final BenchmarkResultPrinter printer = BenchmarkResultPrinter();
+
+  const StandardMethodCodec codec = StandardMethodCodec();
+  final Stopwatch watch = Stopwatch();
+  const String methodName = 'something';
+  watch.start();
+  for (int i = 0; i < _kNumIterations; i += 1) {
+    codec.encodeMethodCall(const MethodCall(methodName));
+  }
+  watch.stop();
+
+  printer.addResult(
+    description: 'StandardMethodCodec null',
+    value: watch.elapsedMicroseconds.toDouble() / _kNumIterations,
+    unit: 'us per iteration',
+    name: 'StandardMethodCodec_null',
+  );
+
+  watch.reset();
+  watch.start();
+  for (int i = 0; i < _kNumIterations; i += 1) {
+    codec.encodeMethodCall(const MethodCall(methodName, 12345));
+  }
+  watch.stop();
+
+  printer.addResult(
+    description: 'StandardMethodCodec int',
+    value: watch.elapsedMicroseconds.toDouble() / _kNumIterations,
+    unit: 'us per iteration',
+    name: 'StandardMethodCodec_int',
+  );
+
+  watch.reset();
+
+  watch.start();
+  for (int i = 0; i < _kNumIterations; i += 1) {
+    codec.encodeMethodCall(
+        const MethodCall(methodName, 'This is a performance test.'));
+  }
+  watch.stop();
+
+  printer.addResult(
+    description: 'StandardMethodCodec string',
+    value: watch.elapsedMicroseconds.toDouble() / _kNumIterations,
+    unit: 'us per iteration',
+    name: 'StandardMethodCodec_string',
+  );
+
+  watch.reset();
+  watch.start();
+  for (int i = 0; i < _kNumIterations; i += 1) {
+    codec.encodeMethodCall(const MethodCall(
+        methodName, <Object>[1234, 'This is a performance test.', 1.25, true]));
+  }
+  watch.stop();
+
+  printer.addResult(
+    description: 'StandardMethodCodec heterogenous list',
+    value: watch.elapsedMicroseconds.toDouble() / _kNumIterations,
+    unit: 'us per iteration',
+    name: 'StandardMethodCodec_heterogenous_list',
+  );
+
+  watch.reset();
+  watch.start();
+  for (int i = 0; i < _kNumIterations; i += 1) {
+    codec.encodeMethodCall(const MethodCall(methodName, <String, Object>{
+      'integer': 1234,
+      'string': 'This is a performance test.',
+      'float': 1.25,
+      'boolean': true
+    }));
+  }
+  watch.stop();
+
+  printer.addResult(
+    description: 'StandardMethodCodec heterogenous map',
+    value: watch.elapsedMicroseconds.toDouble() / _kNumIterations,
+    unit: 'us per iteration',
+    name: 'StandardMethodCodec_heterogenous_map',
+  );
+
+  watch.reset();
+
+  printer.printToStdout();
+}

dev/devicelab/lib/tasks/microbenchmarks.dart

@@ -61,6 +61,7 @@ TaskFunction createMicrobenchmarkTask() {
       ...await _runMicrobench('lib/language/sync_star_semantics_bench.dart'),
       ...await _runMicrobench('lib/foundation/all_elements_bench.dart'),
       ...await _runMicrobench('lib/foundation/change_notifier_bench.dart'),
+      ...await _runMicrobench('lib/foundation/standard_method_codec_bench.dart'),
       ...await _runMicrobench('lib/foundation/standard_message_codec_bench.dart'),
       ...await _runMicrobench('lib/foundation/timeline_bench.dart'),
     };

packages/flutter/lib/src/services/message_codecs.dart

@@ -9,6 +9,8 @@ import 'package:flutter/foundation.dart' show ReadBuffer, WriteBuffer;
 
 import 'message_codec.dart';
 
+const int _writeBufferStartCapacity = 64;
+
 /// [MessageCodec] with unencoded binary messages represented using [ByteData].
 ///
 /// On Android, messages will be represented using `java.nio.ByteBuffer`.
@@ -310,7 +312,7 @@ class StandardMessageCodec implements MessageCodec<Object?> {
   ByteData? encodeMessage(Object? message) {
     if (message == null)
       return null;
-    final WriteBuffer buffer = WriteBuffer(startCapacity: 64);
+    final WriteBuffer buffer = WriteBuffer(startCapacity: _writeBufferStartCapacity);
     writeValue(buffer, message);
     return buffer.done();
   }
@@ -575,7 +577,7 @@ class StandardMethodCodec implements MethodCodec {
 
   @override
   ByteData encodeMethodCall(MethodCall methodCall) {
-    final WriteBuffer buffer = WriteBuffer();
+    final WriteBuffer buffer = WriteBuffer(startCapacity: _writeBufferStartCapacity);
     messageCodec.writeValue(buffer, methodCall.method);
     messageCodec.writeValue(buffer, methodCall.arguments);
     return buffer.done();
@@ -594,7 +596,7 @@ class StandardMethodCodec implements MethodCodec {
 
   @override
   ByteData encodeSuccessEnvelope(Object? result) {
-    final WriteBuffer buffer = WriteBuffer();
+    final WriteBuffer buffer = WriteBuffer(startCapacity: _writeBufferStartCapacity);
     buffer.putUint8(0);
     messageCodec.writeValue(buffer, result);
     return buffer.done();
@@ -602,7 +604,7 @@ class StandardMethodCodec implements MethodCodec {
 
   @override
   ByteData encodeErrorEnvelope({ required String code, String? message, Object? details}) {
-    final WriteBuffer buffer = WriteBuffer();
+    final WriteBuffer buffer = WriteBuffer(startCapacity: _writeBufferStartCapacity);
     buffer.putUint8(1);
     messageCodec.writeValue(buffer, code);
     messageCodec.writeValue(buffer, message);