README.md

Parallel Quick Sort

This example implements a parallel version of quicksort by napa.js, and compares its performance to that of a serial version. It demonstrates

1. How does napa.js transport a TypedArray (JavaScript built-in objects) among napa worker transparently. The TypedArray is created from a SharedArrayBuffer.
2. How does napa.js accelerate a computation heavy task by parallelization.

How to run

1. Go to directory of examples/tutorial/parallel-quick-sort.
2. Run npm install to install napajs.
3. Run node parallel-quick-sort.js.

Note: This example involves TypedArray and SharedArrayBuffer. It requires Node v9.0.0 or newer.

Program output

The table below shows results of the serial quicksort and the parallel one.

quickSort:              It took ( 1006 ) MS to sort an array with  4194304  elements.
parallelQuickSort:      It took ( 388 ) MS to sort an array with  4194304  elements.

Both of them were executed on a 4 millions length Float64Array. The parallel implementation by napa.js brought 60+% performance gain under my test environment below.

Name	Value
Processor	Intel(R) Xeon(R) CPU E5-2620 0 @ 2.00GHz, 2000 Mhz, 6 Core(s), 12 Logical Processor(s)
System Type	x64-based PC
Physical Memory	32.0 GB
OS version	Microsoft Windows Server 2016 Datacenter