Class: OneApm::Agent::SampledBuffer

Inherits:
EventBuffer show all
Extended by:
Forwardable
Defined in:
lib/one_apm/support/event_buffer/sampled_buffer.rb

Instance Attribute Summary collapse

Attributes inherited from EventBuffer

#capacity

Instance Method Summary collapse

Methods inherited from EventBuffer

#<<, #append, #full?, #note_dropped, #num_dropped, #num_seen, #sample_rate, #size, #to_a

Constructor Details

#initialize(capacity) ⇒ SampledBuffer

Returns a new instance of SampledBuffer.



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# File 'lib/one_apm/support/event_buffer/sampled_buffer.rb', line 15

def initialize(capacity)
  super
  @captured_lifetime = 0
  @seen_lifetime     = 0
end

Instance Attribute Details

#captured_lifetime ⇒ Object (readonly)

Returns the value of attribute captured_lifetime.



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# File 'lib/one_apm/support/event_buffer/sampled_buffer.rb', line 12

def captured_lifetime
  @captured_lifetime
end

#seen_lifetime ⇒ Object (readonly)

Returns the value of attribute seen_lifetime.



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# File 'lib/one_apm/support/event_buffer/sampled_buffer.rb', line 12

def seen_lifetime
  @seen_lifetime
end

Instance Method Details

#append_event(x) ⇒ Object 



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# File 'lib/one_apm/support/event_buffer/sampled_buffer.rb', line 27

def append_event(x)
  if @items.size < @capacity
    @items << x
    return x
  else
    m = rand(@seen) # [0, @seen)
    if m < @capacity
      @items[m] = x
      return x
    else
      # discard current sample
      return nil
    end
  end
end

#reset! ⇒ Object 



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# File 'lib/one_apm/support/event_buffer/sampled_buffer.rb', line 21

def reset!
  @captured_lifetime += @items.size
  @seen_lifetime     += @seen
  super
end

#sample_rate_lifetime ⇒ Object 



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# File 'lib/one_apm/support/event_buffer/sampled_buffer.rb', line 44

def sample_rate_lifetime
  @captured_lifetime > 0 ? (@captured_lifetime.to_f / @seen_lifetime) : 0.0
end