balancer

@perf-tools/balancer

A tool for load balancing within the limit of a single frame and not only.

npm i --save @perf-tools/balancer

Description

Often, need to reduce the load, for example when listening to the onscroll event or take the operation as deferred. Usually, in such a situation we use: debounce and throttle. These are very good tools, but sometimes want more, namely controlling the execution within one frame of the animation or use idle-process.

It is for this created @perf-tools/balancer. You add deferred calls into it, and it controls that their execution does not take more than 13ms, otherwise it moves them to idle-process.

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API

• call — add a deferred call to a balancer
• debounce — created a debounced function
• cancel — cancel a deferred call
• uniqueKey — a factory of unique keys to replacing a deferred call, with the same key
• Bits — advanced knowledge

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call(fn, ctx?, args?, options?): Task

Add a deferred call to a balancer.

• fn: Function
• ctx: object
• args: any[]
• options: TaskOptions
  • key: TaskUniqueKey
  • flags: number — a bitmask

import {call} from '@perf-tools/balancer';

call(function () {
	// some code
});

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debounce<T>(fn, ctx?, args?, options?): T & {cancel(): void}

Created a debounced function

• fn: Function
• ctx: object
• args: any[]
• options: TaskOptions
  • key: TaskUniqueKey
  • flags: number — a bitmask

import {debounce} from '@perf-tools/balancer';

const handleScroll = debounce(function () {
	// some code
});

// Or boosted (without arguments)
// const handleScroll = debounce(function () {}, null, null, {flags: F_NO_ARGS});

document.addEventListener('scroll', handleScroll, true);

// Anywhere else
handleScroll.cancel(); // cancel a deferred call
document.addEventListener('scroll', handleScroll, true);

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cancel(task: Task)

Cancel a deferred call

• task: Task — the task of a deferred call

import {call, cancel} from '@perf-tools/balancer';

const task = call(function () {
	// some code
});

// Anywhere else
cancel(task);

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uniqueKey(name: string): TaskUniqueKey

A factory of unique keys to replacing a deferred call, with the same key

• name: name — any name (does not affect anything)

import {call, uniqueKey} from '@perf-tools/balancer';

const key = uniqueKey('demo');

call(function () { console.log('One'); }, null, [], {key});
call(function () { console.log('Two'); }, null, [], {key});

// Console output:
//  Two

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Bits

• F_CTX — use free a context
• F_NO_ARGS — ignore arguments for boost performance a debounced function
• F_IMPORTANT — even if the task is too heavy, it will not be moved to the idle-process and will continue to run per frame

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Development

• npm i
• npm test, code coverage