Allow about:tracing Counters to be selected

chrome/browser/resources/tracing/timeline_analysis.js

+// Copyright (c) 2012 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+'use strict';
+
+/**
+ * @fileoverview TimelineView visualizes TRACE_EVENT events using the
+ * tracing.Timeline component and adds in selection summary and control buttons.
+ */
+cr.define('tracing', function() {
+  function tsRound(ts) {
+    return Math.round(ts * 1000.0) / 1000.0;
+  }
+
+  function getPadding(text, width) {
+    width = width || 0;
+
+    if (typeof text != 'string')
+      text = String(text);
+
+    if (text.length >= width)
+      return '';
+
+    var pad = '';
+    for (var i = 0; i < width - text.length; i++)
+      pad += ' ';
+    return pad;
+  }
+
+  function leftAlign(text, width) {
+    return text + getPadding(text, width);
+  }
+
+  function rightAlign(text, width) {
+    return getPadding(text, width) + text;
+  }
+
+
+  function getTextForSelection(selection) {
+    var text = '';
+    var sliceHits = selection.getSliceHits();
+    var counterSampleHits = selection.getCounterSampleHits();
+
+    if (sliceHits.length == 1) {
+      var c0Width = 14;
+      var slice = sliceHits[0].slice;
+      text = 'Selected item:\n';
+      text += leftAlign('Title', c0Width) + ': ' + slice.title + '\n';
+      text += leftAlign('Start', c0Width) + ': ' +
+          tsRound(slice.start) + ' ms\n';
+      text += leftAlign('Duration', c0Width) + ': ' +
+          tsRound(slice.duration) + ' ms\n';
+      if (slice.durationInUserTime)
+        text += leftAlign('Duration (U)', c0Width) + ': ' +
+            tsRound(slice.durationInUserTime) + ' ms\n';
+
+      var n = 0;
+      for (var argName in slice.args) {
+        n += 1;
+      }
+      if (n > 0) {
+        text += leftAlign('Args', c0Width) + ':\n';
+        for (var argName in slice.args) {
+          var argVal = slice.args[argName];
+          text += leftAlign(' ' + argName, c0Width) + ': ' + argVal + '\n';
+        }
+      }
+    } else if (sliceHits.length > 1) {
+      var c0Width = 55;
+      var c1Width = 12;
+      var c2Width = 5;
+      text = 'Slices:\n';
+      var tsLo = sliceHits.range.min;
+      var tsHi = sliceHits.range.max;
+
+      // compute total sliceHits duration
+      var titles = sliceHits.map(function(i) { return i.slice.title; });
+
+      var slicesByTitle = {};
+      for (var i = 0; i < sliceHits.length; i++) {
+        var slice = sliceHits[i].slice;
+        if (!slicesByTitle[slice.title])
+          slicesByTitle[slice.title] = {
+            slices: []
+          };
+        slicesByTitle[slice.title].slices.push(slice);
+      }
+      var totalDuration = 0;
+      for (var sliceGroupTitle in slicesByTitle) {
+        var sliceGroup = slicesByTitle[sliceGroupTitle];
+        var duration = 0;
+        for (i = 0; i < sliceGroup.slices.length; i++)
+          duration += sliceGroup.slices[i].duration;
+        totalDuration += duration;
+
+        text += ' ' +
+            leftAlign(sliceGroupTitle, c0Width) + ': ' +
+            rightAlign(tsRound(duration) + 'ms', c1Width) + '   ' +
+            rightAlign(String(sliceGroup.slices.length), c2Width) +
+            ' occurrences' + '\n';
+      }
+
+      text += leftAlign('*Totals', c0Width) + ' : ' +
+          rightAlign(tsRound(totalDuration) + 'ms', c1Width) + '   ' +
+          rightAlign(String(sliceHits.length), c2Width) + ' occurrences' +
+          '\n';
+
+      text += '\n';
+
+      text += leftAlign('Selection start', c0Width) + ' : ' +
+          rightAlign(tsRound(tsLo) + 'ms', c1Width) +
+          '\n';
+      text += leftAlign('Selection extent', c0Width) + ' : ' +
+          rightAlign(tsRound(tsHi - tsLo) + 'ms', c1Width) +
+          '\n';
+    }
+
+    if (counterSampleHits.length == 1) {
+      text = 'Selected counter:\n';
+      var c0Width = 55;
+      var hit = counterSampleHits[0];
+      var ctr = hit.counter;
+      var sampleIndex = hit.sampleIndex;
+      var values = [];
+      for (var i = 0; i < ctr.numSeries; ++i)
+        values.push(ctr.samples[ctr.numSeries * sampleIndex + i]);
+      text += leftAlign('Title', c0Width) + ': ' + ctr.name + '\n';
+      text += leftAlign('Timestamp', c0Width) + ': ' +
+        tsRound(ctr.timestamps[sampleIndex]) + ' ms\n';
+      if (ctr.numSeries > 1)
+        text += leftAlign('Values', c0Width) + ': ' + values.join('\n') + '\n';
+      else
+        text += leftAlign('Value', c0Width) + ': ' + values.join('\n') + '\n';
+
+    } else if (counterSampleHits.length > 1 && sliceHits.length == 0) {
+      text += 'Analysis of multiple counters not yet implemented. ' +
+          'Pick a single counter.';
+    }
+    return text;
+  }
+
+  var TimelineAnalysisView = cr.ui.define('div');
+
+  TimelineAnalysisView.prototype = {
+    __proto__: HTMLDivElement.prototype,
+
+    decorate: function() {
+      this.className = 'timeline-analysis';
+    },
+
+    set selection(selection) {
+      this.textContent = getTextForSelection(selection);
+    }
+  };
+
+  return {
+    TimelineAnalysisView: TimelineAnalysisView,
+  };
+});