Module: MemoryProfiler::TopN

Included in:
StatHash
Defined in:
lib/memory_profiler/top_n.rb

Instance Method Summary collapse

Instance Method Details

#top_n(max, metric) ⇒ Object

Fast approach for determining the top_n entries in a Hash of Stat objects. Returns results for both memory (memsize summed) and objects allocated (count) as a tuple.



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# File 'lib/memory_profiler/top_n.rb', line 5

def top_n(max, metric)

  stats_by_metric = self.values.map! { |stat| [stat.send(metric), stat.memsize] }

  stat_totals = stats_by_metric.group_by { |metric_value, _memsize| metric_value }.
      map { |key, values| [key, values.reduce(0) { |sum, item| _key, memsize = item ; sum + memsize }, values.size] }

  stats_by_memsize = stat_totals.sort_by! { |metric, memsize, _count| [-memsize, metric] }.first(max).
      map! { |metric, memsize, _count| { data: metric, count: memsize } }
  stats_by_count = stat_totals.sort_by! { |metric, _memsize, count| [-count, metric] }.first(max).
      map! { |metric, _memsize, count| { data: metric, count: count } }

  [stats_by_memsize, stats_by_count]

end