lib/ps.js
function ps (pids, options, done) {
  var pArg = pids.join(',')
  var args = ['-o', 'etime,pid,ppid,pcpu,rss,time', '-p', pArg]

  if (PLATFORM === 'aix') {
    args = ['-o', 'etime,pid,ppid,pcpu,rssize,time', '-p', pArg]
  }

  bin('ps', args, function (err, stdout, code) {
    if (err) return done(err)
    if (code === 1) {
      return done(new Error('No maching pid found'))
    }
    if (code !== 0) {
      return done(new Error('pidusage ps command exited with code ' + code))
    }
    var date = Date.now()

    // Example of stdout on *nix.
    // ELAPSED: format is [[dd-]hh:]mm:ss
    // RSS: is counted as blocks of 1024 bytes
    // TIME: format is [[dd-]hh:]mm:ss
    // %CPU: goes from 0 to vcore * 100
    //
    // Refs: http://www.manpages.info/linux/ps.1.html
    // NB: The columns are returned in the order given inside the -o option
    //
    //    ELAPSED   PID  PPID  %CPU     RSS        TIME
    // 2-40:50:53   430     1   3.0    5145  1-02:03:04
    //   40:50:53   432   430   0.0    2364  1-01:02:03
    //   01:50:50   727     1  10.0  348932       14:27
    //      00:20  7166     1   0.1    3756        0:00

    // Example of stdout on Darwin
    // ELAPSED: format is [[dd-]hh:]mm:ss
    // RSS: is counted as blocks of 1024 bytes
    // TIME: format is [[dd-]hh:]mm:ss.cc (cc are centiseconds)
    // %CPU: goes from 0 to vcore * 100
    //
    // Refs: https://ss64.com/osx/ps.html
    // NB: The columns are returned in the order given inside the -o option
    //
    //    ELAPSED   PID  PPID  %CPU     RSS           TIME
    // 2-40:50:53   430     1   3.0    5145  1-02:03:04.07
    //   40:50:53   432   430   0.0    2364  1-01:02:03.10
    //   01:50:50   727     1  10.0  348932       14:27.26
    //      00:20  7166     1   0.1    3756        0:00.02

    stdout = stdout.split(os.EOL)

    var statistics = {}
    for (var i = 1; i < stdout.length; i++) {
      var line = stdout[i].trim().split(/\s+/)

      if (!line || line.length !== 6) {
        continue
      }

      var pid = parseInt(line[1], 10)
      var hst = history.get(pid, options.maxage)
      if (hst === undefined) hst = {}

      var ppid = parseInt(line[2], 10)
      var memory = parseInt(line[4], 10) * 1024
      var etime = parseTime(line[0])
      var ctime = parseTime(line[5], true)

      var total = (ctime - (hst.ctime || 0))
      // time elapsed between calls in seconds
      var seconds = Math.abs(hst.elapsed !== undefined ? etime - hst.elapsed : etime)
      var cpu = seconds > 0 ? (total / seconds) * 100 : 0

      statistics[pid] = {
        cpu: cpu,
        memory: memory,
        ppid: ppid,
        pid: pid,
        ctime: ctime,
        elapsed: etime,
        timestamp: date
      }

      history.set(pid, statistics[pid], options.maxage)
    }

    done(null, statistics)
  })
}
function ps (pids, options, done) {
  var pArg = pids.join(',')
  var args = ['-o', 'etime,pid,ppid,pcpu,rss,time', '-p', pArg]

  if (PLATFORM === 'aix') {
    args = ['-o', 'etime,pid,ppid,pcpu,rssize,time', '-p', pArg]
  }

  bin('ps', args, function (err, stdout, code) {
    if (err) return done(err)
    if (code === 1) {
      return done(new Error('No maching pid found'))
    }
    if (code !== 0) {
      return done(new Error('pidusage ps command exited with code ' + code))
    }
    var date = Date.now()

    // Example of stdout on *nix.
    // ELAPSED: format is [[dd-]hh:]mm:ss
    // RSS: is counted as blocks of 1024 bytes
    // TIME: format is [[dd-]hh:]mm:ss
    // %CPU: goes from 0 to vcore * 100
    //
    // Refs: http://www.manpages.info/linux/ps.1.html
    // NB: The columns are returned in the order given inside the -o option
    //
    //    ELAPSED   PID  PPID  %CPU     RSS        TIME
    // 2-40:50:53   430     1   3.0    5145  1-02:03:04
    //   40:50:53   432   430   0.0    2364  1-01:02:03
    //   01:50:50   727     1  10.0  348932       14:27
    //      00:20  7166     1   0.1    3756        0:00

    // Example of stdout on Darwin
    // ELAPSED: format is [[dd-]hh:]mm:ss
    // RSS: is counted as blocks of 1024 bytes
    // TIME: format is [[dd-]hh:]mm:ss.cc (cc are centiseconds)
    // %CPU: goes from 0 to vcore * 100
    //
    // Refs: https://ss64.com/osx/ps.html
    // NB: The columns are returned in the order given inside the -o option
    //
    //    ELAPSED   PID  PPID  %CPU     RSS           TIME
    // 2-40:50:53   430     1   3.0    5145  1-02:03:04.07
    //   40:50:53   432   430   0.0    2364  1-01:02:03.10
    //   01:50:50   727     1  10.0  348932       14:27.26
    //      00:20  7166     1   0.1    3756        0:00.02

    stdout = stdout.split(os.EOL)

    var statistics = {}
    for (var i = 1; i < stdout.length; i++) {
      var line = stdout[i].trim().split(/\s+/)

      if (!line || line.length !== 6) {
        continue
      }

      var pid = parseInt(line[1], 10)
      var hst = history.get(pid, options.maxage)
      if (hst === undefined) hst = {}

      var ppid = parseInt(line[2], 10)
      var memory = parseInt(line[4], 10) * 1024
      var etime = parseTime(line[0])
      var ctime = parseTime(line[5], true)

      var total = (ctime - (hst.ctime || 0))
      // time elapsed between calls in seconds
      var seconds = Math.abs(hst.elapsed !== undefined ? etime - hst.elapsed : etime)
      var cpu = seconds > 0 ? (total / seconds) * 100 : 0

      statistics[pid] = {
        cpu: cpu,
        memory: memory,
        ppid: ppid,
        pid: pid,
        ctime: ctime,
        elapsed: etime,
        timestamp: date
      }

      history.set(pid, statistics[pid], options.maxage)
    }

    done(null, statistics)
  })
}
function ps ( pids , options , done ) { var pArg = pids . join ( ',' ) var args = [ '-o' , 'etime,pid,ppid,pcpu,rss,time' , '-p' , pArg ] if ( PLATFORM === 'aix' ) { args = [ '-o' , 'etime,pid,ppid,pcpu,rssize,time' , '-p' , pArg ] } bin ( 'ps' , args , function ( err , stdout , code ) { if ( err ) return done ( err ) if ( code === 1 ) { return done ( new Error ( 'No maching pid found' ) ) } if ( code !== 0 ) { return done ( new Error ( 'pidusage ps command exited with code ' + code ) ) } var date = Date . now ( ) // Example of stdout on *nix. // ELAPSED: format is [[dd-]hh:]mm:ss // RSS: is counted as blocks of 1024 bytes // TIME: format is [[dd-]hh:]mm:ss // %CPU: goes from 0 to vcore * 100 // // Refs: http://www.manpages.info/linux/ps.1.html // NB: The columns are returned in the order given inside the -o option // //    ELAPSED   PID  PPID  %CPU     RSS        TIME // 2-40:50:53   430     1   3.0    5145  1-02:03:04 //   40:50:53   432   430   0.0    2364  1-01:02:03 //   01:50:50   727     1  10.0  348932       14:27 //      00:20  7166     1   0.1    3756        0:00 // Example of stdout on Darwin // ELAPSED: format is [[dd-]hh:]mm:ss // RSS: is counted as blocks of 1024 bytes // TIME: format is [[dd-]hh:]mm:ss.cc (cc are centiseconds) // %CPU: goes from 0 to vcore * 100 // // Refs: https://ss64.com/osx/ps.html // NB: The columns are returned in the order given inside the -o option // //    ELAPSED   PID  PPID  %CPU     RSS           TIME // 2-40:50:53   430     1   3.0    5145  1-02:03:04.07 //   40:50:53   432   430   0.0    2364  1-01:02:03.10 //   01:50:50   727     1  10.0  348932       14:27.26 //      00:20  7166     1   0.1    3756        0:00.02 stdout = stdout . split ( os . EOL ) var statistics = { } for ( var i = 1 ; i < stdout . length ; i ++ ) { var line = stdout [ i ] . trim ( ) . split ( / \s+ / ) if ( ! line || line . length !== 6 ) { continue } var pid = parseInt ( line [ 1 ] , 10 ) var hst = history . get ( pid , options . maxage ) if ( hst === undefined ) hst = { } var ppid = parseInt ( line [ 2 ] , 10 ) var memory = parseInt ( line [ 4 ] , 10 ) * 1024 var etime = parseTime ( line [ 0 ] ) var ctime = parseTime ( line [ 5 ] , true ) var total = ( ctime - ( hst . ctime || 0 ) ) // time elapsed between calls in seconds var seconds = Math . abs ( hst . elapsed !== undefined ? etime - hst . elapsed : etime ) var cpu = seconds > 0 ? ( total / seconds ) * 100 : 0 statistics [ pid ] = { cpu : cpu , memory : memory , ppid : ppid , pid : pid , ctime : ctime , elapsed : etime , timestamp : date } history . set ( pid , statistics [ pid ] , options . maxage ) } done ( null , statistics ) } ) }
Get pid informations through ps command.
@param  {Number[]} pids
@param  {Object} options
@param  {Function} done(err, stat)
Get pid informations through ps command .