Class: Appsignal::GarbageCollectionProfiler

Inherits:
Object
  • Object
show all
Defined in:
lib/appsignal/garbage_collection_profiler.rb

Overview

Appsignal::GarbageCollectionProfiler wraps Ruby’s GC::Profiler to be able to track garbage collection time for multiple transactions, while constantly clearing GC::Profiler’s total_time to make sure it doesn’t leak memory by keeping garbage collection run samples in memory.

Instance Method Summary collapse

Constructor Details

#initialize ⇒ GarbageCollectionProfiler

Returns a new instance of GarbageCollectionProfiler.



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# File 'lib/appsignal/garbage_collection_profiler.rb', line 8

def initialize
  @total_time = 0
end

Instance Method Details

#total_time ⇒ Object

Whenever #total_time is called, the current GC::Profiler.total_time gets added to @total_time, after which GC::Profiler.clear is called to prevent it from leaking memory. A class-level lock is used to make sure garbage collection time is never counted more than once.

Whenever @total_time gets above two billion milliseconds (about 23 days), it’s reset to make sure the result fits in a signed 32-bit integer.



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# File 'lib/appsignal/garbage_collection_profiler.rb', line 20

def total_time
  lock.synchronize do
    @total_time += (internal_profiler.total_time * 1000).round
    internal_profiler.clear
  end

  if @total_time > 2_000_000_000
    @total_time = 0
  end

  @total_time
end