Zero-overhead asynchronous parallel/each/map function call
npm install fastparallelZero-overhead parallel function call for node.js. Also supports each
and map!
Benchmark for doing 3 calls setImmediate 1 million times:
``
benchSetImmediate*1000000: 1378.514ms
benchAsyncParallel*1000000: 1740.304ms
benchAsyncEach*1000000: 1566.517ms
benchAsyncMap*1000000: 1687.518ms
benchNeoParallel*1000000: 1388.223ms
benchNeoEach*1000000: 1473.006ms
benchNeoMap*1000000: 1402.986ms
benchInsyncParallel*1000000: 1957.863ms
benchInsyncEach*1000000: 1383.822ms
benchInsyncMap*1000000: 1822.954ms
benchItemsParallel*1000000: 1690.118ms
benchParallelize*1000000: 1570.064ms
benchFastParallel*1000000: 1536.692ms
benchFastParallelNoResults*1000000: 1363.145ms
benchFastParallelEachResults*1000000: 1508.134ms
benchFastParallelEach*1000000: 1325.314ms
Obtained on node 12.18.2, on a dedicated server.
If you need zero-overhead series function call, check out
fastseries. If you need a fast work queue
check out fastq. If you need to run fast
waterfall calls, use fastfall.
__The major difference between version 1.x.x and 2.x.x is the order of
results__, this is now ready to replace async in every case.
`js
var parallel = require('fastparallel')({
// this is a function that will be called
// when a parallel completes
released: completed,
// if you want the results, then here you are
results: true
})
parallel(
{}, // what will be this in the functions
[something, something, something], // functions to call
42, // the first argument of the functions
done // the function to be called when the parallel ends
)
function something (arg, cb) {
setImmediate(cb, null, 'myresult')
}
function done (err, results) {
console.log('parallel completed, results:', results)
}
function completed () {
console.log('parallel completed!')
}
`
`js
var parallel = require('fastparallel')({
// this is a function that will be called
// when a parallel completes
released: completed,
// if you want the results, then here you are
// passing false disables map
results: true
})
parallel(
{}, // what will be this in the functions
something, // functions to call
[1, 2, 3], // the first argument of the functions
done // the function to be called when the parallel ends
)
function something (arg, cb) {
setImmediate(cb, null, 'myresult')
}
function done (err, results) {
console.log('parallel completed, results:', results)
}
function completed () {
console.log('parallel completed!')
}
`
The done` function will be called only once, even if more than one error happen.
This library works by caching the latest used function, so that running a new parallel
does not cause any memory allocations.
1. This library is caching functions a lot.
2. V8 optimizations: thanks to caching, the functions can be optimized by V8 (if they are optimizable, and I took great care of making them so).
3. Don't use arrays if you just need a queue. A linked list implemented via processes is much faster if you don't need to access elements in between.
4. Accept passing a this for the functions. Thanks to this hack, you can extract your functions, and place them in a outer level where they are not created at every execution.
ISC