See https://github.com/crystal-lang/crystal/issues/6340

Is Crystal slower than Ruby in generating randoms?

While playing around with Crystal I noticed that Ruby is quite faster than Crystal in generating randoms.

I wrote a Crystal script that performs 10 million randoms (hex, base64, rand and random_bytes) and measures the times.

I did the same in Ruby and found that Ruby script is significantly faster than Crystal.

Is this expected? Are Crystal randoms more secure and thus more expensive?

Generator	Amount	Time in Crystal	Time in Ruby
hex	10M	~ 47.4s	~ 8.8s
base64	10M	~ 52.1s	~ 10.6s
rand	10M	~ 43.8s	~ 6.1s
random_bytes	10M	~ 47.8s	~ 5.8s

(In Crystal I used Random, in Ruby I used SecureRandom)

$ crystal -v
Crystal 0.25.1 (2018-06-29)

LLVM: 5.0.2
Default target: x86_64-apple-macosx

$ ruby -v
ruby 2.5.1p57 (2018-03-29 revision 63029) [x86_64-darwin17]

Environment

• macOS High Sierra 10.13.5 (17F77)
• 1.4 GHz Intel Core i7
• 8 GB 1867 MHz LPDDR3