Object#equal? is faster than comparing object_ids

benchmark.rb

#!/usr/bin/ruby

# Warming up --------------------------------------
#         a.equal?(b)    670.728k i/100ms
#         a.id == b.id   367.019k i/100ms
# Calculating -------------------------------------
#         a.equal?(b)       6.588M (± 2.5%) i/s -     33.536M in   5.093834s
#         a.id == b.id      3.646M (± 3.0%) i/s -     18.351M in   5.038107s
# 
# Comparison:
#         a.equal?(b) :  6588048.0 i/s
#         a.id == b.id:  3646134.0 i/s - 1.81x  slower

require "benchmark/ips"

a = Object.new
b = Object.new

Benchmark.ips do |x|
  x.report("a.equal?(b) ") do |times|
    i = 0
    while (i += 1) < times
      Object.new.equal?(Object.new)
    end
  end

  x.report("a.id == b.id") do |times|
    i = 0
    while (i += 1) < times
      Object.new.object_id == Object.new.object_id
    end
  end

  x.compare!
end

BTW this measurement was in Ruby 3.2.1.