Masking benchmark

bench.ex

defmodule Bench do
  def orig(payload, mask) do
    maskstream = <<mask::32>> |> :binary.bin_to_list() |> Stream.cycle()

    payload
    |> :binary.bin_to_list()
    |> Enum.zip(maskstream)
    |> Enum.map(fn {x, y} -> Bitwise.bxor(x, y) end)
    |> :binary.list_to_bin()
  end

  def mask(payload, mask, acc \\ <<>>)

  def mask(payload, mask, acc) when is_integer(mask), do: mask(payload, <<mask::32>>, acc)

  def mask(<<h::8, rest::binary>>, <<current::8, mask::24>>, acc) do
    mask(rest, <<mask::24, current::8>>, acc <> <<Bitwise.bxor(h, current)::8>>)
  end

  def mask(<<>>, _mask, acc), do: acc
end

bench.exs

mask = 1234

Benchee.run(
  %{
    "old" => fn input -> Bench.orig(input, mask) end,
    "new" => fn input -> Bench.mask(input, mask) end,
  },
  time: 10,
  memory_time: 2,
  inputs: %{
    "small" => String.duplicate("a", 1_000),
    "medium" => String.duplicate("a", 100_000),
    "large" => String.duplicate("a", 10_000_000)
  }
)

results.txt

Operating System: Linux
CPU Information: AMD Ryzen 7 3700X 8-Core Processor
Number of Available Cores: 16
Available memory: 15.54 GB
Elixir 1.14.0
Erlang 25.1

Benchmark suite executing with the following configuration:
warmup: 2 s
time: 10 s
memory time: 2 s
reduction time: 0 ns
parallel: 1
inputs: large, medium, small
Estimated total run time: 1.40 min

Benchmarking new with input large ...
Benchmarking new with input medium ...
Benchmarking new with input small ...
Benchmarking old with input large ...
Benchmarking old with input medium ...
Benchmarking old with input small ...

##### With input large #####
Name           ips        average  deviation         median         99th %
new           1.19         0.84 s     ±3.93%         0.85 s         0.90 s
old          0.110         9.07 s     ±7.40%         9.07 s         9.55 s

Comparison: 
new           1.19
old          0.110 - 10.79x slower +8.23 s

Memory usage statistics:

Name    Memory usage
new          1.71 GB
old          5.88 GB - 3.43x memory usage +4.17 GB

**All measurements for memory usage were the same**

##### With input medium #####
Name           ips        average  deviation         median         99th %
new         133.36        7.50 ms     ±5.13%        7.47 ms        8.62 ms
old          12.80       78.13 ms     ±3.27%       78.46 ms       80.64 ms

Comparison: 
new         133.36
old          12.80 - 10.42x slower +70.63 ms

Memory usage statistics:

Name    Memory usage
new         17.55 MB
old         58.99 MB - 3.36x memory usage +41.44 MB

**All measurements for memory usage were the same**

##### With input small #####
Name           ips        average  deviation         median         99th %
new         6.51 K      153.69 μs    ±54.83%      154.69 μs      348.61 μs
old         2.20 K      453.62 μs    ±17.34%      450.90 μs      623.49 μs

Comparison: 
new         6.51 K
old         2.20 K - 2.95x slower +299.93 μs

Memory usage statistics:

Name    Memory usage
new        180.52 KB
old        616.16 KB - 3.41x memory usage +435.63 KB

**All measurements for memory usage were the same**