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NodeJS

https://blog.heroku.com/archives/2015/11/10/node-habits-2016

Learning

node-gyp

Hotfix
For Windows users, sometimes will fix your problem!
set VCTargetsPath=C:\Program Files (x86)\MSBuild\Microsoft.Cpp\v4.0\V140

Debugging

debug-options
The node binary has tons of options to play with

node --optimize_for_size --max_old_space_size=920 --gc_interval=100
node --prof-process --perf_basic_prof --trace-gc --abort-on-uncaught-exception

Modules

There are a number of modules you should check out for debugging your node.js application. I use heapdump,blocked & memwatch in production with an endpoint to get stats and trigger dumps to debug production apps.

'use strict';

// Ideally you have an endpoint that only accepts localhost
// requests to trigger a heapdump
const heapdump = require('heapdump');
const blocked  = require('blocked');
const memwatch = require('memwatch');
const gc       = require('gc-stats');
const procfs   = require('procfs-stats');

const ps = procfs(process.pid);

ps.io(function(err,io){
  console.log('my process has done this much io', io);
});

ps.stat(function(err,io){
  console.log('my process has done this much io', io);
});

gc.on('stats', function (stats) {
  console.log('GC happened', stats);
});

Performance

gcore `pgrep node`  # core dump for mdb?
perf record -F 99 -p `pgrep -n node` -g -- sleep 30

Links