Method: LinuxStat::CPU.stat

Defined in:
lib/linux_stat/cpu.rb

.stat(sleep = ticks_to_ms_t5) ⇒ Object Also known as: usages

stat(sleep = 1.0 / LinuxStat::Sysconf.sc_clk_tck * 5)

Where sleep is the delay to gather the data.

The minimum possible value at anytime is 1.0 / LinuxStat::Sysconf.sc_clk_tck

This method returns the cpu usage of all threads.

The first one is aggregated CPU usage reported by the Linux kernel.

And the consecutive ones are the real core usages.

For example, on a system with 4 threads:

LinuxStat::CPU.stat

=> {0=>84.38, 1=>100.0, 2=>50.0, 3=>87.5, 4=>87.5}

If the information is not available, it will return an empty Hash



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# File 'lib/linux_stat/cpu.rb', line 23

def stat(sleep = ticks_to_ms_t5)
  return {} unless stat?

  data = IO.readlines('/proc/stat'.freeze).select { |x| x[/^cpu\d*/] }.map! { |x| x.split.map!(&:to_f) }
  sleep(sleep)
  data2 = IO.readlines('/proc/stat'.freeze).select { |x| x[/^cpu\d*/] }.map! { |x| x.split.map!(&:to_f) }

  # On devices like android, the core count can change anytime (hotplugging).
  # I had crashes on Termux.
  # So better just count the min number of CPU and iterate over that
  # If data.length is smaller than data2.length, we don't have enough data to compare.
  dl, d2l = data.length, data2.length
  min = dl > d2l ? d2l : dl

  min.times.reduce({}) do |h, x|
    user, nice, sys, idle, iowait, irq, softirq, steal = *data[x].drop(1)
    user2, nice2, sys2, idle2, iowait2, irq2, softirq2, steal2 = *data2[x].drop(1)

    idle_then, idle_now  = idle + iowait, idle2 + iowait2
    totald = idle_now.+(user2 + nice2 + sys2 + irq2 + softirq2 + steal2) - idle_then.+(user + nice + sys + irq + softirq + steal)

    res = totald.-(idle_now - idle_then).fdiv(totald).abs.*(100)
    res = res.nan? ? 0.0 : res > 100 ? 100.0 : res.round(2)

    h.merge!( x => res )
  end
end