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 24

def any?
	!!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 81

def available
	return nil unless swaps_readable?
	values_t = read_usage
	values_t[0].sum - values_t[1].sum
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 70

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.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 116

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 102

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 34

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 59

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 93

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