var fs = require('fs')
|
var path = require('path')
|
var updateCpu = require('./helpers/cpu')
|
var parallel = require('./helpers/parallel')
|
var history = require('./history')
|
var cpuInfo = null
|
var Buffer = require('safe-buffer').Buffer
|
var SIZE = 1024 // if the stat file is bigger then this I'll buy you a drink
|
|
function noop () {}
|
|
function open (path, history, cb) {
|
if (history.fd) { return cb(null, history.fd) }
|
fs.open(path, 'r', cb)
|
}
|
|
function close (history) {
|
if (history.fd) {
|
fs.close(history.fd, noop)
|
}
|
}
|
|
function readUntilEnd (fd, buf, cb) {
|
var firstRead = false
|
if (typeof buf === 'function') {
|
cb = buf
|
buf = Buffer.alloc(SIZE)
|
firstRead = true
|
}
|
|
fs.read(fd, buf, 0, SIZE, 0, function (err, bytesRead, buffer) {
|
if (err) {
|
cb(err)
|
return
|
}
|
|
var data = Buffer.concat([buf, buffer], firstRead ? bytesRead : buf.length + bytesRead)
|
if (bytesRead === SIZE) {
|
readUntilEnd(fd, data, cb)
|
return
|
}
|
|
cb(null, buf)
|
})
|
}
|
|
function readProcFile (pid, options, done) {
|
var hst = history.get(pid, options.maxage)
|
var again = false
|
if (hst === undefined) {
|
again = true
|
hst = {}
|
}
|
|
// Arguments to path.join must be strings
|
open(path.join('/proc', '' + pid, 'stat'), hst, function (err, fd) {
|
if (err) {
|
if (err.code === 'ENOENT') {
|
err.message = 'No matching pid found'
|
}
|
return done(err, null)
|
}
|
|
if (err) {
|
return done(err)
|
}
|
|
readUntilEnd(fd, function (err, buffer) {
|
if (err) {
|
return done(err)
|
}
|
|
var infos = buffer.toString('utf8')
|
var date = Date.now()
|
|
// https://github.com/arunoda/node-usage/commit/a6ca74ecb8dd452c3c00ed2bde93294d7bb75aa8
|
// preventing process space in name by removing values before last ) (pid (name) ...)
|
var index = infos.lastIndexOf(')')
|
infos = infos.substr(index + 2).split(' ')
|
|
// according to http://man7.org/linux/man-pages/man5/proc.5.html (index 0 based - 2)
|
// In kernels before Linux 2.6, start was expressed in jiffies. Since Linux 2.6, the value is expressed in clock ticks
|
var stat = {
|
ppid: parseInt(infos[1]),
|
utime: parseFloat(infos[11]) * 1000 / cpuInfo.clockTick,
|
stime: parseFloat(infos[12]) * 1000 / cpuInfo.clockTick,
|
cutime: parseFloat(infos[13]) * 1000 / cpuInfo.clockTick,
|
cstime: parseFloat(infos[14]) * 1000 / cpuInfo.clockTick,
|
start: parseFloat(infos[19]) * 1000 / cpuInfo.clockTick,
|
rss: parseFloat(infos[21]),
|
uptime: cpuInfo.uptime * 1000,
|
fd: fd
|
}
|
|
var memory = stat.rss * cpuInfo.pageSize
|
|
// https://stackoverflow.com/a/16736599/3921589
|
var childrens = options.childrens ? stat.cutime + stat.cstime : 0
|
// process usage since last call in seconds
|
var total = (stat.stime - (hst.stime || 0) + stat.utime - (hst.utime || 0) + childrens)
|
// time elapsed between calls in seconds
|
var seconds = Math.abs(hst.uptime !== undefined ? stat.uptime - hst.uptime : stat.start - stat.uptime)
|
var cpu = seconds > 0 ? (total / seconds) * 100 : 0
|
|
history.set(pid, stat, options.maxage, close)
|
|
if (again) {
|
return readProcFile(pid, options, done)
|
}
|
|
return done(null, {
|
cpu: cpu,
|
memory: memory,
|
ctime: stat.utime + stat.stime,
|
elapsed: stat.uptime - stat.start,
|
timestamp: date,
|
pid: pid,
|
ppid: stat.ppid
|
})
|
})
|
})
|
}
|
|
function procfile (pids, options, done) {
|
updateCpu(cpuInfo, function (err, result) {
|
if (err) return done(err)
|
|
cpuInfo = result
|
var fns = {}
|
|
pids.forEach(function (pid, i) {
|
fns[pid] = function (cb) {
|
readProcFile(pid, options, cb)
|
}
|
})
|
|
parallel(fns, { graceful: true }, done)
|
})
|
}
|
|
module.exports = procfile
|
