Class: Process::Metrics::Host::Memory::Linux::CgroupV1

Inherits:
Object
  • Object
show all
Defined in:
lib/process/metrics/host/memory/linux/cgroup_v1.rb

Overview

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

Constant Summary collapse

CGROUP_V1_UNLIMITED_THRESHOLD = 
2**60
DEFAULT_CGROUP_ROOT = 
"/sys/fs/cgroup"

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(cgroup_root: nil) ⇒ CgroupV1

Initialize the cgroup v1 memory reader.



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# File 'lib/process/metrics/host/memory/linux/cgroup_v1.rb', line 29

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

Class Method Details

.supported?(cgroup_root = DEFAULT_CGROUP_ROOT) ⇒ Boolean

Whether cgroup v1 memory metrics are available.

Returns:

  • (Boolean) 


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# File 'lib/process/metrics/host/memory/linux/cgroup_v1.rb', line 17

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

Instance Method Details

#capture ⇒ Object

Capture host memory from the cgroup v1 filesystem.



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# File 'lib/process/metrics/host/memory/linux/cgroup_v1.rb', line 35

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