Performance worse with ESLint

[Akkuma]

I tried 8, 4, and 2 processes and in every case I was seeing worse performance using this than letting eslint just run in 1 process. The build without is about 6s for eslint, and 17s with 2 processes and worse with 4/8.

[teppeis]

@Akkuma The effect depends on the situation.
Please tell me the detail of your project.

[Akkuma]

What specific details are you looking for? File count? Grunt config?

[teppeis]

File count? Grunt config?

yes. and the github repo if possible.

[Akkuma]

Gruntfile

module.exports = function (grunt) {
  var path = require('path');

  // Loads the task which will time each other task
  require('time-grunt')(grunt);

  // Loads configurations from a sub-folder
  require('load-grunt-config')(grunt, {
    //path to task.js files, defaults to grunt dir
    configPath: path.join(process.cwd(), 'src/scripts/grunt'), 
    //auto grunt.initConfig
    init: true,
    data: {
      environment: 'local'
    },
    // Can optionally pass options to load-grunt-tasks.
    // If you set to false, it will disable auto loading tasks.
    loadGruntTasks: {
      pattern: 'grunt-*',
      config: require('./package.json'),
      scope: 'devDependencies'
    }
  });

  // Configure grunt tasks
  require('./src/scripts/grunt/tasks').registerTasks(grunt);
};

There are roughly 90 files that are being ran through eslint. I also switched to jit-grunt, which isn't shown there as that is in a different branch waiting to be merged.

[teppeis]

The Gruntfile is just bootstrap file. Can I get grunt config for grunt-parallelize and eslint?

[Akkuma]

Config for grunt-parallelize was tried with

options: {
  processes: 2 //also tried 4 and 8
}

ESLint that I'm using is a fork of https://github.com/airbnb/javascript/blob/master/packages/eslint-config-airbnb/base/index.js with jsx turned off

[dzotos]

I have the same problem actually with JShint. Trying to process 100 js files and triples the time for each process.

[teppeis]

@dzotos Please show me the repo to reproduce.

[dzotos]

I'm curently working on a private repo, soon I'll try to reproduce in a public one.

jshint: {
            src: [
                '<%= app_files.js %>'
            ],
            test: [
                '<%= app_files.jsunit %>'
            ],
            gruntfile: [
                'Gruntfile.js'
            ],
            all: {
                src: ['<%= app_files.js %>', '<%= app_files.jsunit %>', 'Gruntfile.js']
            },
            options: {
                curly: true,
                immed: true,
                newcap: true,
                noarg: true,
                sub: true,
                boss: true,
                eqnull: true
            },
            globals: {}
        },

        parallelize: {
            options: {
                processes: 2
            },
            jshint: {
                all: true
            }
        },

Thats my JShint block.

[lyuboraykov]

I'm having the same issue in a big grunt file, here're the tasks I want to parallelize:

browserify: {
      static_dist: {
        options: {
          watch: true
        },
        files: {
          'assets/build/scripts/analytics.js': ['assets/scripts/analytics/analytics.js'],
         // some more files here, about 40
        }
      },
      dynamic_dist: {
        options: {
          watch: true
        },
        files: [{
          expand: true,
          cwd: 'assets/',
          src:['scripts/test-scripts/*.js'],
          dest: 'assets/build/'
        }]
      }

Then I have:

    parallelize: {
      browserify: {
        // Run browserify:static_dist task with 4 child processeses in parallel.
        static_dist: 4,
        dynamic_dist: 4
      },
      options: {
        processes: 4
      }
    },

And the call itself:

grunt.registerTask('build:js', 'Build javascript.', ['parallelize:browserify:static_dist', 'parallelize:browserify:dynamic_dist']);

The result is that each task takes 4 times more time. And is executed 4 times sequentially.