2 DEFAULT_MEASUREMENT_STATISTICS_REQUIREMENTS
,
3 DEFAULT_WORKER_CHOICE_STRATEGY_OPTIONS
5 import type { IPool
} from
'../pool'
6 import type { IWorker
} from
'../worker'
7 import { AbstractWorkerChoiceStrategy
} from
'./abstract-worker-choice-strategy'
9 type IWorkerChoiceStrategy
,
11 type TaskStatisticsRequirements
,
12 type WorkerChoiceStrategyOptions
13 } from
'./selection-strategies-types'
16 * Selects the next worker with a fair share scheduling algorithm.
17 * Loosely modeled after the fair queueing algorithm: https://en.wikipedia.org/wiki/Fair_queuing.
19 * @typeParam Worker - Type of worker which manages the strategy.
20 * @typeParam Data - Type of data sent to the worker. This can only be structured-cloneable data.
21 * @typeParam Response - Type of execution response. This can only be structured-cloneable data.
23 export class FairShareWorkerChoiceStrategy
<
24 Worker
extends IWorker
,
28 extends AbstractWorkerChoiceStrategy
<Worker
, Data
, Response
>
29 implements IWorkerChoiceStrategy
{
31 public readonly taskStatisticsRequirements
: TaskStatisticsRequirements
= {
37 waitTime
: DEFAULT_MEASUREMENT_STATISTICS_REQUIREMENTS
,
46 * Workers' virtual task end execution timestamp.
48 private workersVirtualTaskEndTimestamp
: number[] = []
52 pool
: IPool
<Worker
, Data
, Response
>,
53 opts
: WorkerChoiceStrategyOptions
= DEFAULT_WORKER_CHOICE_STRATEGY_OPTIONS
56 this.setTaskStatisticsRequirements(this.opts
)
60 public reset (): boolean {
61 this.workersVirtualTaskEndTimestamp
= []
66 public update (workerNodeKey
: number): boolean {
67 this.computeWorkerVirtualTaskEndTimestamp(workerNodeKey
)
72 public choose (): number {
73 return this.fairShareNextWorkerNodeKey()
77 public remove (workerNodeKey
: number): boolean {
78 this.workersVirtualTaskEndTimestamp
.splice(workerNodeKey
, 1)
82 private fairShareNextWorkerNodeKey (): number {
83 let minWorkerVirtualTaskEndTimestamp
= Infinity
84 for (const [workerNodeKey
] of this.pool
.workerNodes
.entries()) {
85 if (this.workersVirtualTaskEndTimestamp
[workerNodeKey
] == null) {
86 this.computeWorkerVirtualTaskEndTimestamp(workerNodeKey
)
88 const workerVirtualTaskEndTimestamp
=
89 this.workersVirtualTaskEndTimestamp
[workerNodeKey
]
91 this.isWorkerNodeReady(workerNodeKey
) &&
92 workerVirtualTaskEndTimestamp
< minWorkerVirtualTaskEndTimestamp
94 minWorkerVirtualTaskEndTimestamp
= workerVirtualTaskEndTimestamp
95 this.nextWorkerNodeKey
= workerNodeKey
98 return this.nextWorkerNodeKey
102 * Computes the worker node key virtual task end timestamp.
104 * @param workerNodeKey - The worker node key.
106 private computeWorkerVirtualTaskEndTimestamp (workerNodeKey
: number): void {
107 this.workersVirtualTaskEndTimestamp
[workerNodeKey
] =
108 this.getWorkerVirtualTaskEndTimestamp(
110 this.getWorkerVirtualTaskStartTimestamp(workerNodeKey
)
114 private getWorkerVirtualTaskEndTimestamp (
115 workerNodeKey
: number,
116 workerVirtualTaskStartTimestamp
: number
118 const workerTaskRunTime
=
119 this.opts
.measurement
=== Measurements
.elu
120 ? this.getWorkerTaskElu(workerNodeKey
)
121 : this.getWorkerTaskRunTime(workerNodeKey
)
122 return workerVirtualTaskStartTimestamp
+ workerTaskRunTime
125 private getWorkerVirtualTaskStartTimestamp (workerNodeKey
: number): number {
128 this.workersVirtualTaskEndTimestamp
[workerNodeKey
] ?? -Infinity