Ruby 2.1.7 vs 2.2.3垃圾回收

Question

我正在看到一些奇怪的潜在红宝石2.2.3 gc相关问题,从单词列表生成前缀尝试.可疑代码在这里:

def insert(word)
      return if word.nil? || word.empty?
      node = self
      counter = 0
      l = word.length
      #TODO _ why is this not being garbage collected?
      word.bytes.each do |i|
        counter += 1
        node.children[i] ||= Node.new(i.chr, node, counter == l)
        node = node.children[i]
        node.terminal = true if counter == l
      end
    end

它是从字符串列表中调用的 - 就这样

words.each_with_index do |word, i|
    @root.insert(word)

当我对此进行一些内存分析时,我看到ruby 2.2.3-railsexpress中的总mem用量为~68MB:

Measure Mode: memory
Thread ID: 70102347546980
Fiber ID: 70102348363420
Total: 68688.375000
Sort by: self_time

 %self      total      self      wait     child     calls  name
 20.03  13755.000 13755.000     0.000     0.000   293398   FastAutocomplete::Node#initialize
  9.05   6218.875  6218.875     0.000     0.000    86036   String#bytes
  6.26  66665.562  4298.438     0.000 62367.125    86040  *Array#each
  1.50   1028.969  1028.969     0.000     0.000   230540   Hash#keys
  0.98    677.219   676.438     0.000     0.781        1   Array#map

当我使用2.1.7时,我只看到大约22MB的使用情况:

    Measure Mode: memory
Thread ID: 70216772377340
Fiber ID: 70216782765400
Total: 22009.125000
Sort by: self_time

 %self      total      self      wait     child     calls  name
 62.49  13754.391 13754.391     0.000     0.000   293398   FastAutocomplete::Node#initialize
 28.25   6218.641  6218.641     0.000     0.000    86036   String#bytes
  4.67   1028.078  1028.078     0.000     0.000   230540   Hash#keys
  3.07    676.797   676.203     0.000     0.594        1   Array#map
  1.27    280.203   280.203     0.000     0.000   116093   Thread::Queue#enq
  0.07     19.297    15.516     0.000     3.781        9   JSON::Ext::Generator::GeneratorMethods::Hash#to_json

我已经尝试了很多东西,比如在整个创建过程中跟踪GC.stats,但是没有注意到任何特别有用的东西.我也尝试过使用string.each_char或string.split('').每个(即不同的迭代器).

关于为什么2.2.3使用3x内存的任何想法？这导致我们的一些服务器爆炸.