Class: NurseAndrea::MemorySampler

Inherits:
Object
  • Object
show all
Defined in:
lib/nurse_andrea/memory_sampler.rb

Constant Summary collapse

INTERVAL_SECONDS = 
30

Class Method Summary collapse

Class Method Details

.rss_bytes ⇒ Object

Returns RSS in bytes. Works on Linux (/proc) and macOS (ps).



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# File 'lib/nurse_andrea/memory_sampler.rb', line 27

def self.rss_bytes
  if File.exist?("/proc/self/status")
    line = File.readlines("/proc/self/status").find { |l| l.start_with?("VmRSS:") }
    return nil unless line
    kb = line.split[1].to_i
    kb * 1024
  else
    kb = `ps -o rss= -p #{Process.pid}`.strip.to_i
    return nil if kb == 0
    kb * 1024
  end
rescue
  nil
end

.sample_and_enqueue ⇒ Object 



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# File 'lib/nurse_andrea/memory_sampler.rb', line 42

def self.sample_and_enqueue
  bytes = rss_bytes
  return unless bytes && bytes > 0

  MetricsShipper.instance.enqueue(
    name:      "process.memory.rss",
    value:     bytes,
    unit:      "bytes",
    tags:      { service: NurseAndrea.config.service_name },
    timestamp: Time.now.utc.iso8601(3)
  )
end

.start ⇒ Object 



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# File 'lib/nurse_andrea/memory_sampler.rb', line 5

def self.start
  return @thread if @thread&.alive?

  @thread = Thread.new do
    loop do
      sleep INTERVAL_SECONDS
      sample_and_enqueue
    rescue => e
      NurseAndrea.debug("[NurseAndrea] MemorySampler error: #{e.message}")
    end
  end
  @thread.abort_on_exception = false
  @thread.name = "NurseAndrea::MemorySampler"
  @thread
end

.stop ⇒ Object 



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# File 'lib/nurse_andrea/memory_sampler.rb', line 21

def self.stop
  @thread&.kill
  @thread = nil
end