Exceptions benchmark

exceptions_benchmark.rb

require 'benchmark/ips'

def rescue_exception(divider)
  1 / divider
rescue ZeroDivisionError
end

def without_rescue(divider)
  1 / divider
end

Benchmark.ips do |x|
  x.report('rescue') do |t|
    rescue_exception t
  end
  x.report('regular') do |t|
    without_rescue t
  end
  x.compare!
end

results.txt

Calculating -------------------------------------
              rescue   141.144k i/100ms
             regular   143.577k i/100ms
-------------------------------------------------
              rescue    142.007B (±17.3%) i/s -    182.810B
             regular    144.436B (±17.4%) i/s -    183.715B

Comparison:
             regular: 144435990041.5 i/s
              rescue: 142006866116.1 i/s - 1.02x slower

[Finished in 15.8s]

Your code suggest that you run in benchmark the same method twice (rescue_exception).