discourse/script/biggest_objects.rb

# frozen_string_literal: true

# simple script to measure largest objects in memory post boot

exec "RAILS_ENV=production ruby #{__FILE__}" if ENV["RAILS_ENV"] != "production"

require "objspace"

ObjectSpace.trace_object_allocations do
  require File.expand_path("../../config/environment", __FILE__)

  begin
    Rails.application.routes.recognize_path("abc")
  rescue StandardError
    nil
  end

  # load up the yaml for the localization bits, in master process
  I18n.t(:posts)

  RailsMultisite::ConnectionManagement.each_connection do
    (ActiveRecord::Base.connection.tables - %w[schema_migrations versions]).each do |table|
      begin
        table.classify.constantize.first
      rescue StandardError
        nil
      end
    end
  end
end

5.times { GC.start(full_mark: true, immediate_sweep: true) }

[String, Array, Hash].each do |klass|
  ObjectSpace
    .each_object(klass)
    .sort { |a, b| b.length <=> a.length }
    .first(50)
    .each do |obj|
      puts "#{klass} size: #{obj.length} #{ObjectSpace.allocation_sourcefile(obj)} #{ObjectSpace.allocation_sourceline(obj)}"
    end
end