Profiler Take 2

tools/tracesummary.dart

Index: tools/tracesummary.dart
diff --git a/tools/tracesummary.dart b/tools/tracesummary.dart
new file mode 100644
index 0000000000000000000000000000000000000000..3c67351c27f0897bc0d5c03b74dc2cc4fe1ec11c
--- /dev/null
+++ b/tools/tracesummary.dart
@@ -0,0 +1,129 @@
+// Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+// Print a summary of a profile trace.
+
+import 'dart:convert';
+import 'dart:io';
+
+class TraceSymbol {
+  final String name;
+  int exclusive = 0;
+  int inclusive = 0;
+  TraceSymbol(this.name);
+}
+
+class TraceSummary {
+  Map<String, TraceSymbol> _symbols = {};
+  List _events = [];
+  List<TraceSymbol> _stack = [];
+  List<TraceSymbol> _topExclusive = [];
+  List<TraceSymbol> _topInclusive = [];
+
+  void _processEventsFromFile(String name) {
+    var file = new File(name);
+    var events = [];
+    try {
+      var contents = file.readAsStringSync();
+      events = JSON.decode(contents);
+    } catch (e) {
+      print('Exception for $name $e');
+    }
+    _processEvents(events);
+  }
+
+  void _processBegin(Map event) {
+    var name = event['name'];
+    if (name == '<no frame>') {
+      return;
+    }
+    var symbol = _symbols[name];
+    if (symbol == null) {
+      symbol = new TraceSymbol(name);
+      _symbols[name] = symbol;
+    }
+    // Start at 1 because 0 will always be the isolate.
+    for (var i = 1; i < _stack.length; i++) {
+      // Bump inclusive count for all frames.
+      symbol.inclusive++;
+    }
+    _stack.add(symbol);
+    if (_stack.length > 1) {
+      // Only if we aren't the isolate.
+      symbol.exclusive++;
+    }
+  }
+
+  void _processEnd(Map event) {
+    var name = event['name'];
+    if (name == '<no frame>') {
+      return;
+    }
+    var symbol = _stack.last;
+    if (symbol.name != name) {
+      throw new StateError('$name not found at top of stack.');
+    }
+    _stack.removeLast();
+  }
+
+  void _processEvents(List events) {
+    for (var i = 0; i < events.length; i++) {
+      Map event = events[i];
+      if (event['ph'] == 'M') {
+        // Ignore.
+      } else if (event['ph'] == 'B') {
+        _processBegin(event);
+      } else if (event['ph'] == 'E') {
+        _processEnd(event);
+      }
+    }
+  }
+
+
+  static const NUM_SYMBOLS = 10;
+
+  void _findTopExclusive() {
+    _topExclusive = _symbols.values.toList();
+    _topExclusive.sort((a, b) {
+      return b.exclusive - a.exclusive;
+    });
+  }
+
+
+  void _findTopInclusive() {
+    _topInclusive = _symbols.values.toList();
+    _topInclusive.sort((a, b) {
+      return b.inclusive - a.inclusive;
+    });
+  }
+
+  void summarize(String input) {
+    _processEventsFromFile(input);
+    _findTopExclusive();
+    _findTopInclusive();
+    _print();
+  }
+
+  void _print() {
+    print('Top ${NUM_SYMBOLS} exlusive symbols:');
+    _topExclusive.getRange(0, NUM_SYMBOLS).forEach((a) {
+      print('${a.exclusive} ${a.name}');
+    });
+    print('');
+    print('Top ${NUM_SYMBOLS} inclusive symbols:');
+    _topInclusive.getRange(0, NUM_SYMBOLS).forEach((a) {
+      print('${a.inclusive} ${a.name}');
+    });
+  }
+}
+
+main(List<String> arguments) {
+  if (arguments.length < 1) {
+    print('${Platform.executable} ${Platform.script} <input>');
+    return;
+  }
+  String input = arguments[0];
+  TraceSummary ts = new TraceSummary();
+  ts.summarize(input);
+}