discourse/script/diff_heaps.rb

# frozen_string_literal: true

# to be used to compare ruby heaps generated in 2.1
# can isolate memory leaks
#
# rbtrace -p 15193 -e 'Thread.new{require "objspace"; ObjectSpace.trace_object_allocations_start; GC.start(full_mark: true); ObjectSpace.dump_all(output: File.open("heap.json","w"))}.join'
#
#
require "json"

if ARGV.length != 2
  puts "Usage: diff_heaps [ORIG.json] [AFTER.json]"
  exit 1
end

origs = Set.new

File
  .open(ARGV[0], "r")
  .each_line do |line|
    parsed = JSON.parse(line)
    origs << parsed["address"] if parsed && parsed["address"]
  end

diff = []

File
  .open(ARGV[1], "r")
  .each_line do |line|
    parsed = JSON.parse(line)
    if parsed && parsed["address"]
      diff << parsed if origs.exclude? parsed["address"]
    end
  end

diff
  .group_by { |x| [x["type"], x["file"], x["line"]] }
  .map { |x, y| [x, y.count] }
  .sort { |a, b| b[1] <=> a[1] }
  .each { |x, y| puts "Leaked #{y} #{x[0]} objects at: #{x[1]}:#{x[2]}" }