nsolid-manager/nsolid/console/test/simulator/scenarios/high-cpu.js

A manager that sets up and runs N|Solid for you

/**
 * Tries to maintain high CPU usage while still releasing to event loop
 */

"use strict"

const usage = require('usage')

process.title = 'high-cpu'

const MIN_CYCLES = 1000

const TARGET_CPU_USAGE = 90

// min number of consecutive times must hit or miss target before adjusting cycles
const ADJUSTMENT_NEEDED_THRESHOLD = 3

let cycles = MIN_CYCLES
let reachedTargetUsage = 0
let needsMoreCycles = 0

;(function check() {
  usage.lookup(process.pid, (err, result) => {
    if (err) throw err

    if (result.cpu < TARGET_CPU_USAGE) {
      reachedTargetUsage = 0
      needsMoreCycles++
    } else {
      needsMoreCycles = 0
      reachedTargetUsage++
    }

    if (needsMoreCycles > ADJUSTMENT_NEEDED_THRESHOLD) {
      cycles *= 3
    }
    if (reachedTargetUsage > ADJUSTMENT_NEEDED_THRESHOLD) {
      cycles /= 4
    }
    cycles = Math.max(Math.floor(cycles), MIN_CYCLES)
    setTimeout(check)
  })
  work(cycles)
}())

/**
 * CPU 'work'
 */

function work(cycles) {
  let a = 0
  for (let i=0; i<cycles; i++) {
    // bunch of random math
    a += Math.sqrt(Math.pow(Math.sqrt(Math.sin(i)), Math.sqrt(Math.sin(i)))
                   / Math.pow(Math.sqrt(Math.sin(i)), Math.sqrt(Math.sin(i))))
                   + Math.sqrt(Math.pow(Math.sqrt(Math.sin(i)),
                   Math.sqrt(Math.sin(i))) / Math.pow(Math.sqrt(Math.sin(i)),
                   Math.sqrt(Math.sin(i))))
  }
  return a
}