benchmark-ips PoC

ips_autoptr.rb

require File.expand_path(File.join(File.dirname(__FILE__), "ips_helper"))

require 'benchmark/ips'
require 'ffi'

class TestPtr < FFI::AutoPointer
  def self.release(ptr)
    LibC.free(ptr);
  end
end

module LibC
  extend FFI::Library
  ffi_lib FFI::Library::LIBC
  attach_function :malloc, [ :long ], TestPtr, :ignore_error => true
  attach_function :malloc2, :malloc, [ :long ], :pointer, :ignore_error => true
  attach_function :free, [ :pointer ], :void, :ignore_error => true
  def self.finalizer(ptr) 
    proc { LibC.free(ptr) }
  end
end

report = []
report << benchmark("malloc", :hold => true) do |x|
  x.report("AutoPointer.new #{RUBY_ENGINE}#{RUBY_VERSION} with") {
    LibC.malloc(4+4)
  }
  x.report("AutoPointer.new #{RUBY_ENGINE}#{RUBY_VERSION} without") {
    LibC.malloc(4)
  }
end



report << benchmark("finalizer", :hold => true) do |x|
  x.report("ObjectSpace finalizer #{RUBY_ENGINE}#{RUBY_VERSION} with") {
    ptr = LibC.malloc2(4+4)
    ptr2 = FFI::Pointer.new(ptr)
    ObjectSpace.define_finalizer(ptr2, LibC.finalizer(ptr))
  }
  x.report("ObjectSpace finalizer #{RUBY_ENGINE}#{RUBY_VERSION} without") {
    ptr = LibC.malloc2(4)
    ptr2 = FFI::Pointer.new(ptr)
    ObjectSpace.define_finalizer(ptr2, LibC.finalizer(ptr))
  }
end

report.each{|x| x.run_comparison} if report.first.data.size > 1

ips_helper.rb

def benchmark(name, hold: false, quiet: true)
  Benchmark.ips(quiet: quiet) do |x|
    x.config(:stats => :bootstrap, :confidence => 95)
    yield x
    x.hold! "#{name}#{RUBY_ENGINE}#{RUBY_VERSION}" if hold
  end
end

output.txt

# Deprecation warnings removed.
narwhal:ffi eroot$ rake ips:all
install -c build/x86_64-darwin17/ffi_c/2.6.0/ffi_c.bundle lib/ffi_c.bundle
cp build/x86_64-darwin17/ffi_c/2.6.0/ffi_c.bundle build/x86_64-darwin17/stage/lib/ffi_c.bundle
/Users/eroot/.rvm/rubies/ruby-2.6.0/bin/ruby -Ilib -Ibuild ips/ips_autoptr.rb

Pausing here -- run Ruby again to measure the next benchmark...

Pausing here -- run Ruby again to measure the next benchmark...
/Users/eroot/.rvm/rubies/ruby-2.6.0/bin/ruby -Ilib -Ibuild ips/ips_helper.rb
narwhal:ffi eroot$ rake ips:all
install -c build/x86_64-darwin17/ffi_c/2.6.0/ffi_c.bundle lib/ffi_c.bundle
cp build/x86_64-darwin17/ffi_c/2.6.0/ffi_c.bundle build/x86_64-darwin17/stage/lib/ffi_c.bundle
/Users/eroot/.rvm/rubies/ruby-2.6.0/bin/ruby -Ilib -Ibuild ips/ips_autoptr.rb

Comparison:
AutoPointer.new ruby2.6.0 without:   442732.6 i/s
AutoPointer.new ruby2.6.0 with:   418828.2 i/s - same-ish: difference falls within error
                   with 95.0% confidence


Comparison:
ObjectSpace finalizer ruby2.6.0 without:   534030.1 i/s
ObjectSpace finalizer ruby2.6.0 with:   497763.6 i/s - 1.07x  (± 0.02) slower
                   with 95.0% confidence

/Users/eroot/.rvm/rubies/ruby-2.6.0/bin/ruby -Ilib -Ibuild ips/ips_helper.rb
narwhal:ffi eroot$