› Process::Metrics › Source › Process › Metrics › Host › Memory › Linux › CgroupV1

`class CgroupV1`

Captures host memory limits and usage from a cgroup v1 filesystem.

Definitions

`def self.supported?(cgroup_root = DEFAULT_CGROUP_ROOT)`

Whether cgroup v1 memory metrics are available.

Signature

parameter　cgroup_root　String | Nil: The root of the cgroup filesystem.
returns　Boolean: Whether the required cgroup v1 files exist.

Implementation

def self.supported?(cgroup_root = DEFAULT_CGROUP_ROOT)
	root = (cgroup_root || DEFAULT_CGROUP_ROOT).to_s.chomp("/")
	
	if File.exist?("#{root}/memory/memory.limit_in_bytes") && File.exist?("#{root}/memory/memory.usage_in_bytes")
		return true
	end
	
	return false
end

`def initialize(cgroup_root: nil)`

Initialize the cgroup v1 memory reader.

Signature

parameter　cgroup_root　String | Nil: The root of the cgroup filesystem.

Implementation

def initialize(cgroup_root: nil)
	@cgroup_root = (cgroup_root || DEFAULT_CGROUP_ROOT).to_s.chomp("/")
end

`def capture`

Capture host memory from the cgroup v1 filesystem.

Signature

returns　Host::Memory | Nil: The captured host memory, if the cgroup has a finite limit.

Implementation

def capture
	total = read_total
	return nil unless total && total.positive?
	
	used = read_used
	return nil unless used
	used = 0 if used.negative?
	used = [used, total].min
	
	swap_total, swap_used = read_swap
	reclaimable = read_reclaimable
	
	return Host::Memory.new(total, used, swap_total, swap_used, reclaimable)
end