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pidusage

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Cross-platform process cpu % and memory usage of a PID.

Synopsis

Ideas from https://github.com/arunoda/node-usage but with no C-bindings.

Please note that if you need to check a Node.JS script process cpu and memory usage, you can use process.cpuUsage and process.memoryUsage since node v6.1.0. This script remain useful when you have no control over the remote script, or if the process is not a Node.JS process.

Usage

var pidusage = require('pidusage')

pidusage(process.pid, function (err, stats) {
  console.log(stats)
  // => {
  //   cpu: 10.0,            // percentage (from 0 to 100*vcore)
  //   memory: 357306368,    // bytes
  //   ppid: 312,            // PPID
  //   pid: 727,             // PID
  //   ctime: 867000,        // ms user + system time
  //   elapsed: 6650000,     // ms since the start of the process
  //   timestamp: 864000000  // ms since epoch
  // }
  cb()
})

// It supports also multiple pids
pidusage([727, 1234], function (err, stats) {
  console.log(stats)
  // => {
  //   727: {
  //     cpu: 10.0,            // percentage (from 0 to 100*vcore)
  //     memory: 357306368,    // bytes
  //     ppid: 312,            // PPID
  //     pid: 727,             // PID
  //     ctime: 867000,        // ms user + system time
  //     elapsed: 6650000,     // ms since the start of the process
  //     timestamp: 864000000  // ms since epoch
  //   },
  //   1234: {
  //     cpu: 0.1,             // percentage (from 0 to 100*vcore)
  //     memory: 3846144,      // bytes
  //     ppid: 727,            // PPID
  //     pid: 1234,            // PID
  //     ctime: 0,             // ms user + system time
  //     elapsed: 20000,       // ms since the start of the process
  //     timestamp: 864000000  // ms since epoch
  //   }
  // }
})

// If no callback is given it returns a promise instead
const stats = await pidusage(process.pid)
console.log(stats)
// => {
//   cpu: 10.0,            // percentage (from 0 to 100*vcore)
//   memory: 357306368,    // bytes
//   ppid: 312,            // PPID
//   pid: 727,             // PID
//   ctime: 867000,        // ms user + system time
//   elapsed: 6650000,     // ms since the start of the process
//   timestamp: 864000000  // ms since epoch
// }

// Avoid using setInterval as they could overlap with asynchronous processing
function compute(cb) {
  pidusage(process.pid, function (err, stats) {
    console.log(stats)
    // => {
    //   cpu: 10.0,            // percentage (from 0 to 100*vcore)
    //   memory: 357306368,    // bytes
    //   ppid: 312,            // PPID
    //   pid: 727,             // PID
    //   ctime: 867000,        // ms user + system time
    //   elapsed: 6650000,     // ms since the start of the process
    //   timestamp: 864000000  // ms since epoch
    // }
    cb()
  })
}

function interval(time) {
  setTimeout(function() {
    compute(function() {
      interval(time)
    })
  }, time)
}

// Compute statistics every second:
interval(1000)

// Above example using async/await
const compute = async () => {
  const stats = await pidusage(process.pid)
  // do something
}

// Compute statistics every second:
const interval = async (time) => {
  setTimeout(async () => {
    await compute()
    interval(time)
  }, time)
}

interval(1000)

Compatibility

Property Linux FreeBSD NetBSD SunOS macOS Win AIX Alpine
cpu ℹ️
memory
pid
ctime
elapsed
timestamp

✅ = Working ℹ️ = Not Accurate ❓ = Should Work ❌ = Not Working

Please if your platform is not supported or if you have reported wrong readings file an issue.

By default, pidusage will use procfile parsing on most unix systems. If you want to use ps instead use the usePs option:

pidusage(pid, {usePs: true})

API

pidusage(pids, [options = {}], [callback]) ⇒ [Promise.<Object>]

Get pid informations.

Kind: global function Returns: Promise.<Object> - Only when the callback is not provided. Access: public

Param Type Description
pids Number | Array.<Number> | String | Array.<String> A pid or a list of pids.
[options] object Options object. See the table below.
[callback] function Called when the statistics are ready. If not provided a promise is returned instead.

options

Setting the options programatically will override environment variables

Param Type Environment variable Default Description
[usePs] boolean PIDUSAGE_USE_PS false When true uses ps instead of proc files to fetch process information
[maxage] number PIDUSAGE_MAXAGE 60000 Max age of a process on history.

PIDUSAGE_SILENT=1 can be used to remove every console message triggered by pidusage.

pidusage.clear()

If needed this function can be used to delete all in-memory metrics and clear the event loop. This is not necessary before exiting as the interval we're registring does not hold up the event loop.

Related

Authors

See also the list of contributors who participated in this project.

License

This project is licensed under the MIT License - see the LICENSE file for details.