Module: LinuxStat::Swap

Defined in:
lib/linux_stat/swap.rb

Class Method Summary collapse

Class Method Details

.any? ⇒ Boolean

Returns true if any swap device is available, else returns false.

If the info isn’t available, it will return an empty Hash.

Returns:

  • (Boolean) 


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# File 'lib/linux_stat/swap.rb', line 22

def any?
  !!IO.foreach('/proc/swaps').drop(1).first
end

.available ⇒ Object

Show total amount of available swap.

The value is in kilobytes.

The return type is a Integer but if the info isn’t available, it will return nil.



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# File 'lib/linux_stat/swap.rb', line 68

def available
  return nil unless swaps_readable?
  values_t = read_usage
  values_t[0].sum - values_t[1].sum
end

.list ⇒ Object

List all swap devices and returns a Hash.

If the info isn’t available, it will return an empty Hash.



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# File 'lib/linux_stat/swap.rb', line 8

def list
  return {} unless swaps_readable?

  file = IO.readlines('/proc/swaps').drop(1)
  file.reduce({}) do |h, x|
    name, *stats = x.strip.split
    h.merge!(name => stats.map! { |v| v.to_i.to_s == v ? v.to_i : v.to_sym })
  end
end

.percent_available ⇒ Object

Shows the percentage of swap available.

The return type is a Float but if the info isn’t available, it will return nil.



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# File 'lib/linux_stat/swap.rb', line 103

def percent_available
  return nil unless swaps_readable?
  values_t = read_usage

  total = values_t[0].sum
  return 0.0 if total == 0

  total.-(values_t[-1].sum).*(100).fdiv(total).round(2)
end

.percent_used ⇒ Object

Show percentage of swap used.

The return type is a Float but if the info isn’t available, it will return nil.



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# File 'lib/linux_stat/swap.rb', line 89

def percent_used
  return nil unless swaps_readable?
  values_t = read_usage

  total = values_t[0].sum
  return 0.0 if total == 0

  values_t[-1].sum.*(100).fdiv(total).round(2)
end

.stat ⇒ Object

Show aggregated used and available swap.

The values are in kilobytes.

The return type is Hash. If the info isn’t available, the return type is an empty Hash.



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# File 'lib/linux_stat/swap.rb', line 32

def stat
  return {} unless swaps_readable?
  values_t = read_usage

  total, used = values_t[0].sum, values_t[-1].sum
  available = total - used
  percent_used = total == 0 ? 0.0 : used.*(100).fdiv(total).round(2)
  percent_available = total == 0.0 ? 0 : available.*(100).fdiv(total).round(2)

  # We have all the methods, but each methods reads the same file
  {
    total: total,
    used: used,
    available: available,
    percent_used: percent_used,
    percent_available: percent_available
  }
end

.total ⇒ Object

Shows total amount of swap.

The value is in kilobytes.

The return type is a Integer but if the info isn’t available, it will return nil.



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# File 'lib/linux_stat/swap.rb', line 57

def total
  return nil unless swaps_readable?
  read_usage[0].sum
end

.used ⇒ Object

Show total amount of used swap.

The value is in kilobytes.

The return type is a Integer but if the info isn’t available, it will return nil.



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# File 'lib/linux_stat/swap.rb', line 80

def used
  return nil unless swaps_readable?
  read_usage[-1].sum
end