| 1 | import Benchmark from 'benny' |
| 2 | import { generateRandomInteger } from '../benchmarks-utils.mjs' |
| 3 | |
| 4 | function generateRandomTasksMap ( |
| 5 | numberOfWorkers, |
| 6 | maxNumberOfTasksPerWorker = 10 |
| 7 | ) { |
| 8 | const tasksArray = [] |
| 9 | for (let i = 0; i < numberOfWorkers; i++) { |
| 10 | const task = [i, generateRandomInteger(maxNumberOfTasksPerWorker)] |
| 11 | tasksArray.push(task) |
| 12 | } |
| 13 | return new Map(tasksArray) |
| 14 | } |
| 15 | |
| 16 | const tasksMap = generateRandomTasksMap(60, 20) |
| 17 | |
| 18 | function loopSelect (tasksMap) { |
| 19 | let minValue = Infinity |
| 20 | let minKey |
| 21 | for (const [key, value] of tasksMap) { |
| 22 | if (value === 0) { |
| 23 | return key |
| 24 | } else if (value < minValue) { |
| 25 | minKey = key |
| 26 | minValue = value |
| 27 | } |
| 28 | } |
| 29 | return [minKey, minValue] |
| 30 | } |
| 31 | |
| 32 | function arraySortSelect (tasksMap) { |
| 33 | const tasksArray = Array.from(tasksMap) |
| 34 | return tasksArray.sort((a, b) => { |
| 35 | if (a[1] < b[1]) { |
| 36 | return -1 |
| 37 | } else if (a[1] > b[1]) { |
| 38 | return 1 |
| 39 | } |
| 40 | return 0 |
| 41 | })[0] |
| 42 | } |
| 43 | |
| 44 | const defaultComparator = (a, b) => { |
| 45 | return a < b |
| 46 | } |
| 47 | |
| 48 | const defaultPivotIndexSelect = (leftIndex, rightIndex) => { |
| 49 | return leftIndex + Math.floor((rightIndex - leftIndex) / 2) |
| 50 | } |
| 51 | |
| 52 | const randomPivotIndexSelect = (leftIndex, rightIndex) => { |
| 53 | return generateRandomInteger(rightIndex, leftIndex) |
| 54 | } |
| 55 | |
| 56 | function swap (array, index1, index2) { |
| 57 | const tmp = array[index1] |
| 58 | array[index1] = array[index2] |
| 59 | array[index2] = tmp |
| 60 | } |
| 61 | |
| 62 | function partition ( |
| 63 | array, |
| 64 | leftIndex, |
| 65 | rightIndex, |
| 66 | pivotIndex, |
| 67 | compare = defaultComparator |
| 68 | ) { |
| 69 | const pivotValue = array[pivotIndex] |
| 70 | swap(array, pivotIndex, rightIndex) |
| 71 | let storeIndex = leftIndex |
| 72 | for (let i = leftIndex; i < rightIndex; i++) { |
| 73 | if (compare(array[i], pivotValue)) { |
| 74 | swap(array, storeIndex, i) |
| 75 | storeIndex++ |
| 76 | } |
| 77 | } |
| 78 | swap(array, rightIndex, storeIndex) |
| 79 | return storeIndex |
| 80 | } |
| 81 | |
| 82 | function selectLoop ( |
| 83 | array, |
| 84 | k, |
| 85 | leftIndex, |
| 86 | rightIndex, |
| 87 | compare = defaultComparator, |
| 88 | pivotIndexSelect = defaultPivotIndexSelect |
| 89 | ) { |
| 90 | while (true) { |
| 91 | if (leftIndex === rightIndex) return array[leftIndex] |
| 92 | let pivotIndex = pivotIndexSelect(leftIndex, rightIndex) |
| 93 | pivotIndex = partition(array, leftIndex, rightIndex, pivotIndex, compare) |
| 94 | if (k === pivotIndex) { |
| 95 | return array[k] |
| 96 | } else if (k < pivotIndex) { |
| 97 | rightIndex = pivotIndex - 1 |
| 98 | } else { |
| 99 | leftIndex = pivotIndex + 1 |
| 100 | } |
| 101 | } |
| 102 | } |
| 103 | |
| 104 | function selectRecursion ( |
| 105 | array, |
| 106 | k, |
| 107 | leftIndex, |
| 108 | rightIndex, |
| 109 | compare = defaultComparator, |
| 110 | pivotIndexSelect = defaultPivotIndexSelect |
| 111 | ) { |
| 112 | if (leftIndex === rightIndex) return array[leftIndex] |
| 113 | let pivotIndex = pivotIndexSelect(leftIndex, rightIndex) |
| 114 | pivotIndex = partition(array, leftIndex, rightIndex, pivotIndex, compare) |
| 115 | if (k === pivotIndex) { |
| 116 | return array[k] |
| 117 | } else if (k < pivotIndex) { |
| 118 | return selectRecursion(array, k, leftIndex, pivotIndex - 1, compare) |
| 119 | } else { |
| 120 | return selectRecursion(array, k, pivotIndex + 1, rightIndex, k, compare) |
| 121 | } |
| 122 | } |
| 123 | |
| 124 | function quickSelectLoop (tasksMap) { |
| 125 | const tasksArray = Array.from(tasksMap) |
| 126 | |
| 127 | return selectLoop(tasksArray, 0, 0, tasksArray.length - 1, (a, b) => { |
| 128 | return a[1] < b[1] |
| 129 | }) |
| 130 | } |
| 131 | |
| 132 | function quickSelectLoopRandomPivot (tasksMap) { |
| 133 | const tasksArray = Array.from(tasksMap) |
| 134 | |
| 135 | return selectLoop( |
| 136 | tasksArray, |
| 137 | 0, |
| 138 | 0, |
| 139 | tasksArray.length - 1, |
| 140 | (a, b) => { |
| 141 | return a[1] < b[1] |
| 142 | }, |
| 143 | randomPivotIndexSelect |
| 144 | ) |
| 145 | } |
| 146 | |
| 147 | function quickSelectRecursion (tasksMap) { |
| 148 | const tasksArray = Array.from(tasksMap) |
| 149 | |
| 150 | return selectRecursion(tasksArray, 0, 0, tasksArray.length - 1, (a, b) => { |
| 151 | return a[1] < b[1] |
| 152 | }) |
| 153 | } |
| 154 | |
| 155 | function quickSelectRecursionRandomPivot (tasksMap) { |
| 156 | const tasksArray = Array.from(tasksMap) |
| 157 | |
| 158 | return selectRecursion( |
| 159 | tasksArray, |
| 160 | 0, |
| 161 | 0, |
| 162 | tasksArray.length - 1, |
| 163 | (a, b) => { |
| 164 | return a[1] < b[1] |
| 165 | }, |
| 166 | randomPivotIndexSelect |
| 167 | ) |
| 168 | } |
| 169 | |
| 170 | Benchmark.suite( |
| 171 | 'Least used worker tasks distribution', |
| 172 | Benchmark.add('Loop select', () => { |
| 173 | loopSelect(tasksMap) |
| 174 | }), |
| 175 | Benchmark.add('Array sort select', () => { |
| 176 | arraySortSelect(tasksMap) |
| 177 | }), |
| 178 | Benchmark.add('Quick select loop', () => { |
| 179 | quickSelectLoop(tasksMap) |
| 180 | }), |
| 181 | Benchmark.add('Quick select loop with random pivot', () => { |
| 182 | quickSelectLoopRandomPivot(tasksMap) |
| 183 | }), |
| 184 | Benchmark.add('Quick select recursion', () => { |
| 185 | quickSelectRecursion(tasksMap) |
| 186 | }), |
| 187 | Benchmark.add('Quick select recursion with random pivot', () => { |
| 188 | quickSelectRecursionRandomPivot(tasksMap) |
| 189 | }), |
| 190 | Benchmark.cycle(), |
| 191 | Benchmark.complete() |
| 192 | ) |