- [`pool = new FixedThreadPool/FixedClusterPool(numberOfThreads/numberOfWorkers, filePath, opts)`](#pool--new-fixedthreadpoolfixedclusterpoolnumberofthreadsnumberofworkers-filepath-opts)
- [`pool = new DynamicThreadPool/DynamicClusterPool(min, max, filePath, opts)`](#pool--new-dynamicthreadpooldynamicclusterpoolmin-max-filepath-opts)
- [`pool.execute(data, name, transferList)`](#poolexecutedata-name-transferlist)
+ - [`pool.start()`](#poolstart)
- [`pool.destroy()`](#pooldestroy)
- [`pool.listTaskFunctions()`](#poollisttaskfunctions)
- [`PoolOptions`](#pooloptions)
### `pool = new DynamicThreadPool/DynamicClusterPool(min, max, filePath, opts)`
`min` (mandatory) Same as _FixedThreadPool_/_FixedClusterPool_ numberOfThreads/numberOfWorkers, this number of workers will be always active
-`max` (mandatory) Max number of workers that this pool can contain, the new created workers will die after a threshold (default is 1 minute, you can override it in your worker implementation).
+`max` (mandatory) Max number of workers that this pool can contain, the newly created workers will die after a threshold (default is 1 minute, you can override it in your worker implementation).
`filePath` (mandatory) Path to a file with a worker implementation
`opts` (optional) An object with the pool options properties described below
This method is available on both pool implementations and returns a promise with the task function execution response.
+### `pool.start()`
+
+This method is available on both pool implementations and will start the minimum number of workers.
+
### `pool.destroy()`
This method is available on both pool implementations and will call the terminate method on each worker.
An object with these properties:
-- `onlineHandler` (optional) - A function that will listen for online event on each worker
-- `messageHandler` (optional) - A function that will listen for message event on each worker
-- `errorHandler` (optional) - A function that will listen for error event on each worker
-- `exitHandler` (optional) - A function that will listen for exit event on each worker
+- `onlineHandler` (optional) - A function that will listen for online event on each worker.
+ Default: `() => {}`
+- `messageHandler` (optional) - A function that will listen for message event on each worker.
+ Default: `() => {}`
+- `errorHandler` (optional) - A function that will listen for error event on each worker.
+ Default: `() => {}`
+- `exitHandler` (optional) - A function that will listen for exit event on each worker.
+ Default: `() => {}`
+
- `workerChoiceStrategy` (optional) - The worker choice strategy to use in this pool:
- `WorkerChoiceStrategies.ROUND_ROBIN`: Submit tasks to worker in a round robin fashion
- `WorkerChoiceStrategies.LEAST_USED`: Submit tasks to the worker with the minimum number of executed, executing and queued tasks
- `WorkerChoiceStrategies.LEAST_BUSY`: Submit tasks to the worker with the minimum tasks total execution and wait time
- `WorkerChoiceStrategies.LEAST_ELU`: Submit tasks to the worker with the minimum event loop utilization (ELU)
- - `WorkerChoiceStrategies.WEIGHTED_ROUND_ROBIN`: Submit tasks to worker by using a [weighted round robin scheduling algorithm](./../docs/worker-choice-strategies.md#weighted-round-robin) based on tasks execution time
- - `WorkerChoiceStrategies.INTERLEAVED_WEIGHTED_ROUND_ROBIN`: Submit tasks to worker by using an [interleaved weighted round robin scheduling algorithm](./../docs/worker-choice-strategies.md#interleaved-weighted-round-robin) based on tasks execution time (experimental)
- - `WorkerChoiceStrategies.FAIR_SHARE`: Submit tasks to worker by using a [fair share scheduling algorithm](./../docs/worker-choice-strategies.md#fair-share) based on tasks execution time (the default) or ELU active time
+ - `WorkerChoiceStrategies.WEIGHTED_ROUND_ROBIN`: Submit tasks to worker by using a [weighted round robin scheduling algorithm](./worker-choice-strategies.md#weighted-round-robin) based on tasks execution time
+ - `WorkerChoiceStrategies.INTERLEAVED_WEIGHTED_ROUND_ROBIN`: Submit tasks to worker by using an [interleaved weighted round robin scheduling algorithm](./worker-choice-strategies.md#interleaved-weighted-round-robin-experimental) based on tasks execution time (experimental)
+ - `WorkerChoiceStrategies.FAIR_SHARE`: Submit tasks to worker by using a [fair share scheduling algorithm](./worker-choice-strategies.md#fair-share) based on tasks execution time (the default) or ELU active time
`WorkerChoiceStrategies.WEIGHTED_ROUND_ROBIN`, `WorkerChoiceStrategies.INTERLEAVED_WEIGHTED_ROUND_ROBIN` and `WorkerChoiceStrategies.FAIR_SHARE` strategies are targeted to heavy and long tasks.
Default: `WorkerChoiceStrategies.ROUND_ROBIN`
- `workerChoiceStrategyOptions` (optional) - The worker choice strategy options object to use in this pool.
Properties:
- - `choiceRetries` (optional) - The number of retries to perform if no worker is eligible.
+ - `retries` (optional) - The number of retries to perform if no worker is eligible.
- `measurement` (optional) - The measurement to use in worker choice strategies: `runTime`, `waitTime` or `elu`.
- - `runTime` (optional) - Use the tasks [median](./../docs/worker-choice-strategies.md#median) runtime instead of the tasks average runtime in worker choice strategies.
- - `waitTime` (optional) - Use the tasks [median](./../docs/worker-choice-strategies.md#median) wait time instead of the tasks average wait time in worker choice strategies.
- - `elu` (optional) - Use the tasks [median](./../docs/worker-choice-strategies.md#median) ELU instead of the tasks average ELU in worker choice strategies.
+ - `runTime` (optional) - Use the tasks [simple moving median](./worker-choice-strategies.md#simple-moving-median) runtime instead of the tasks simple moving average runtime in worker choice strategies.
+ - `waitTime` (optional) - Use the tasks [simple moving median](./worker-choice-strategies.md#simple-moving-median) wait time instead of the tasks simple moving average wait time in worker choice strategies.
+ - `elu` (optional) - Use the tasks [simple moving median](./worker-choice-strategies.md#simple-moving-median) ELU instead of the tasks simple moving average ELU in worker choice strategies.
- `weights` (optional) - The worker weights to use in weighted round robin worker choice strategies: `{ 0: 200, 1: 300, ..., n: 100 }`.
- Default: `{ choiceRetries: 6, runTime: { median: false }, waitTime: { median: false }, elu: { median: false } }`
+ Default: `{ retries: 6, runTime: { median: false }, waitTime: { median: false }, elu: { median: false } }`
+- `startWorkers` (optional) - Start the minimum number of workers at pool creation.
+ Default: `true`
- `restartWorkerOnError` (optional) - Restart worker on uncaught error in this pool.
Default: `true`
- `enableEvents` (optional) - Events emission enablement in this pool.
- `tasksQueueOptions` (optional) - The worker tasks queue options object to use in this pool.
Properties:
+ - `size` (optional) - The maximum number of tasks that can be queued on a worker before flagging it as back pressured. It must be a positive integer.
- `concurrency` (optional) - The maximum number of tasks that can be executed concurrently on a worker. It must be a positive integer.
+ - `taskStealing` (optional) - Task stealing enablement.
+ - `tasksStealingOnBackPressure` (optional) - Tasks stealing enablement on back pressure.
- Default: `{ concurrency: 1 }`
+ Default: `{ size: (pool maximum size)^2, concurrency: 1, taskStealing: true, tasksStealingOnBackPressure: true }`
#### `ThreadPoolOptions extends PoolOptions`