Module: LinuxStat::Swap

Defined in:
lib/linux_stat/swap.rb

Overview

Shows various Swap devices related information of the current system.

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 25

def any?
	return nil unless File.readable?('/proc/swaps'.freeze)
	!!IO.foreach('/proc/swaps'.freeze).first(2)[1]
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 86

def available
	return nil unless swaps_readable?
	values_t = read_usage
	t = values_t[0].reduce(:+)
	u = values_t[1].reduce(:+)
	(t && u) ? t - u : nil
end

.free ⇒ Object

Shows free 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 75

def free
	v = LinuxStat::Sysinfo.freeswap
	v ? v.fdiv(1024).to_i : nil
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 10

def list
	return {} unless swaps_readable?

	file = IO.readlines('/proc/swaps'.freeze).drop(1)
	file.reduce({}) do |h, x|
		name, *stats = x.strip.split
		h.store(name, stats.map! { |v| LinuxStat::Misc.integer?(v) ? v.to_i : v.to_sym })
		h
	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 129

def percent_available
	return nil unless swaps_readable?
	values_t = read_usage

	_total = values_t[0]
	_used = values_t[-1]
	return nil if _total.empty? || _used.empty?

	total, used = _total.reduce(:+), _used.reduce(:+)

	return 0.0 if total == 0

	total.-(used).*(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 109

def percent_used
	return nil unless swaps_readable?
	values_t = read_usage

	_total = values_t[0]
	_used = values_t[-1]
	return nil if _total.empty? || _used.empty?

	total = _total.reduce(:+)
	used = _used.reduce(:+)

	return 0.0 if total == 0

	used.*(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 36

def stat
	return {} unless swaps_readable?
	values_t = read_usage

	_total, _used = values_t[0], values_t[-1]
	return {} if _total.empty? || _used.empty?

	total, used = _total.reduce(:+), _used.reduce(:+)
	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 64

def total
	v = LinuxStat::Sysinfo.totalswap
	v ? v.fdiv(1024).to_i : nil
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 100

def used
	return nil unless swaps_readable?
	read_usage[-1].reduce(:+)
end