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| 1 | +<!doctype html> |
| 2 | +<html> |
| 3 | +<head> |
| 4 | + <meta charset="utf-8"> |
| 5 | + <title>Except Zone</title> |
| 6 | + <link rel="stylesheet" href="style.css"> |
| 7 | + <script src="../zone.js"></script> |
| 8 | + <script src="../except-zone.js"></script> |
| 9 | +</head> |
| 10 | +<body> |
| 11 | + |
| 12 | + <h1>Except Zone</h1> |
| 13 | + |
| 14 | + <p>We want to know about just the events outside of a given function invocation</p> |
| 15 | + |
| 16 | + <button id="b1">Start Profiling</button> |
| 17 | + |
| 18 | + <p id="output"></p> |
| 19 | + |
| 20 | + <script> |
| 21 | + |
| 22 | + |
| 23 | + |
| 24 | + /* |
| 25 | + * Let's say we want to know the CPU cost from some action |
| 26 | + * that includes async tasks. We can do this with zones! |
| 27 | + */ |
| 28 | + |
| 29 | + /* |
| 30 | + * For this demo, we're going to sort an array using an async |
| 31 | + * algorithm when a button is pressed. |
| 32 | + */ |
| 33 | + function sortAndPrintArray (unsortedArray) { |
| 34 | + //zone.reset(); |
| 35 | + asyncBogosort(unsortedArray, function (sortedArray) { |
| 36 | + console.log(sortedArray); |
| 37 | + }); |
| 38 | + } |
| 39 | + |
| 40 | + |
| 41 | + /* |
| 42 | + * This is a really efficient algorithm. |
| 43 | + * |
| 44 | + * First, check if the array is sorted. |
| 45 | + * - If it is, call the callback |
| 46 | + * - If it isn't, randomize the array and recur |
| 47 | + * |
| 48 | + * This implementation is async because JavaScript |
| 49 | + */ |
| 50 | + function asyncBogosort (arr, cb) { |
| 51 | + setTimeout(function () { |
| 52 | + if (isSorted(arr)) { |
| 53 | + cb(arr); |
| 54 | + } else { |
| 55 | + var newArr = arr.slice(0); |
| 56 | + newArr.sort(function () { |
| 57 | + return Math.random() - 0.5; |
| 58 | + }); |
| 59 | + asyncBogosort(newArr, cb); |
| 60 | + } |
| 61 | + }, 0); |
| 62 | + } |
| 63 | + |
| 64 | + function isSorted (things) { |
| 65 | + for (var i = 1; i < things.length; i += 1) { |
| 66 | + if (things[i] < things[i - 1]) { |
| 67 | + return false; |
| 68 | + } |
| 69 | + } |
| 70 | + return true; |
| 71 | + } |
| 72 | + |
| 73 | + |
| 74 | + |
| 75 | + |
| 76 | + /* |
| 77 | + * This zone starts a timer at the start of each task, |
| 78 | + * and stops it at the end. It accumulates the total run |
| 79 | + * time internally, exposing it via `zone.time()` |
| 80 | + * |
| 81 | + * Note that this is the time the CPU is spending doing |
| 82 | + * bogosort, as opposed to the time from the start |
| 83 | + * of the algorithm until it's completion. |
| 84 | + */ |
| 85 | + var profilingZone = (function () { |
| 86 | + var time = 0, |
| 87 | + // use the high-res timer if available |
| 88 | + timer = performance ? |
| 89 | + performance.now.bind(performance) : |
| 90 | + Date.now.bind(Date); |
| 91 | + return { |
| 92 | + onZoneEnter: function () { |
| 93 | + this.start = timer(); |
| 94 | + }, |
| 95 | + onZoneLeave: function () { |
| 96 | + time += timer() - this.start; |
| 97 | + console.log('sorting took ' + zone.time() + ' of CPU time'); |
| 98 | + }, |
| 99 | + time: function () { |
| 100 | + return Math.floor(time*100) / 100 + 'ms'; |
| 101 | + }, |
| 102 | + reset: function () { |
| 103 | + time = 0; |
| 104 | + } |
| 105 | + }; |
| 106 | + }()); |
| 107 | + |
| 108 | + /* |
| 109 | + * Zone that profiles async tasks |
| 110 | + */ |
| 111 | + var myZone = zone.fork(Zone.exceptZone).fork(profilingZone); |
| 112 | + |
| 113 | + |
| 114 | + /* |
| 115 | + * Bind button |
| 116 | + */ |
| 117 | + b1.addEventListener('click', function () { |
| 118 | + myZone.run(function () { |
| 119 | + var unsortedArray = [3,4,1,2,7]; |
| 120 | + sortAndPrintArray(unsortedArray); |
| 121 | + }); |
| 122 | + }); |
| 123 | + |
| 124 | + |
| 125 | + /* |
| 126 | + * There may be other async actions going on in the background. |
| 127 | + * Because this is not in the zone, our profiling ignores it. |
| 128 | + * Nice. |
| 129 | + */ |
| 130 | + function noop () { |
| 131 | + setTimeout(noop, 10*Math.random()); |
| 132 | + } |
| 133 | + noop(); |
| 134 | + </script> |
| 135 | + |
| 136 | +</body> |
| 137 | +</html> |
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