It's just a simple regex benchmark for different programming languages.

Measures how long it takes to find and count non-overlapping occurrences with default settings.

All benchmarks are wrong, but some are useful - Szilard, benchm-ml

I hope this benchmark can be helpful, but it's not only about performance, but each language also has its engine and offers different features (like UTF support, backreferences, capturing groups ...)

Input text

The input text is a concatenation of Learn X in Y minutes repository.

Maybe isn't the best representative text. I'm searching other texts to add to the benchmark.

Regex patterns

• Email: [\w\.+-]+@[\w\.-]+\.[\w\.-]+
• URI: [\w]+://[^/\s?#]+[^\s?#]+(?:\?[^\s#]*)?(?:#[^\s]*)?
• IPv4: (?:(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9])\.){3}(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9])

The above regex patterns aren't the best or the optimal. The focus is the benchmark, not the matching.

The patterns are applied to the whole file.

Measure

Measuring is done inside the programs to avoid include startup, reading and writing times on results.

Elapsed time include pattern compilation, find and count occurrences.

Performance

Docker image was run on: MacBook Pro (16-inch, 2019), 2.4 GHz Intel Core i9, 32 GB 2667 Mhz DDR4 with macOS Big Sur 11.2.3.

Language	Email(ms)	URI(ms)	IP(ms)	Total(ms)
Nim Regex	1.32	26.92	7.84	36.09
Nim	22.70	21.49	6.75	50.94
Rust	26.66	25.70	5.28	57.63
PHP	42.87	46.30	5.17	94.33
C++ Boost	44.97	44.13	15.13	104.23
Javascript	59.00	47.23	1.50	107.73
Perl	94.92	63.96	20.37	179.25
Julia	104.58	86.55	5.01	196.14
C PCRE2	126.10	112.17	13.10	251.37
Crystal	128.19	112.70	13.18	254.07
C# .Net Core	115.05	106.05	42.71	263.81
Dart	104.10	107.64	76.51	288.25
D ldc	165.46	165.20	4.85	335.51
D dmd	187.94	189.92	5.32	383.18
Ruby	233.88	208.85	43.14	485.86
Python PyPy2	158.34	139.70	253.77	551.81
Dart Native	278.54	307.54	5.77	591.85
Python 2	197.92	131.74	294.42	624.08
Kotlin	186.20	223.05	287.49	696.74
Java	198.33	221.87	287.81	708.01
Python PyPy3	258.78	221.89	257.35	738.03
Python 3	273.86	190.79	319.13	783.78
Go	248.14	241.28	360.90	850.32
C++ STL	433.09	344.74	245.66	1023.49
C# Mono	2859.05	2431.87	145.82	5436.75

Optimized

The following results are for the optimized version.

Language	Email(ms)	URI(ms)	IP(ms)	Total(ms)
Rust	11.43	11.40	5.11	27.94
Nim Regex	1.37	25.51	7.27	34.15
Nim	22.79	21.64	6.77	51.21
C PCRE2	46.22	36.92	4.73	87.87
PHP	43.18	46.71	5.23	95.12
C++ Boost	44.68	44.50	15.10	104.28
Javascript	59.20	47.67	1.61	108.48
C# .Net Core	61.76	47.86	11.63	121.25
Perl	96.00	63.39	20.59	179.99
Julia	104.31	87.98	5.16	197.45
Crystal	129.52	116.33	13.12	258.97
Dart	105.82	107.78	78.18	291.78
D ldc	167.60	165.71	5.07	338.37
D dmd	187.66	192.16	5.55	385.37
Ruby	236.93	206.51	43.70	487.14
Python PyPy2	161.33	143.56	258.06	562.96
Dart Native	273.17	306.14	5.89	585.20
Python 2	200.54	132.89	290.26	623.69
Kotlin	184.13	220.31	273.76	678.21
Java	190.74	223.77	275.24	689.75
Python PyPy3	268.41	226.74	261.17	756.32
Python 3	273.70	194.09	322.09	789.88
Go	244.14	238.40	365.27	847.81
C++ STL	433.18	341.07	246.85	1021.10
C# Mono	1400.04	1189.50	145.73	2735.28

• Language: Indicates the language.
• Email(ms), URI(ms), IP(ms): Indicates the time elapsed in milliseconds for finding and counting non-overlapping occurrences for the pattern.
• Total(ms): Indicates the sum of the above times.

Versions and notes

• C: gcc 7.5.0 & PCRE2 10.36-2
• Crystal: crystal 0.35.1 - LLVM: 8.0.0
• C++: g++ 7.5.0 | Boost 1.65.1.0
• C#: dotnet 5.0.201 | Mono 6.12.0.122
• D: DMD v2.089.0 | LDC 1.8.0
• Dart: Dart 2.12.2
• Go: go 1.16.2
• Java: OpenJDK 11.0.10
• Javascript: node v15.13.0
• Julia: Julia 1.6.0
• Kotlin: kotlinc-jvm 1.4.32
• Nim: Nim 1.4.4
• Perl: perl v5.26.1
• PHP: PHP 8.0.3
• Python: Python 2.7.17 | Python 3.6.9 | PyPy 7.3.3
• Ruby: ruby 2.5.1p57
• Rust: rustc 1.51.0 & regex 1.4.5

How to run

The easiest way to run the benchmark is by using Docker.

git clone https://github.com/mariomka/regex-benchmark.git
cd regex-benchmark
docker run --rm -v $(pwd):/var/regex mariomka/regex-benchmark:1.6

Contributing

All contributions are welcome, from tiny optimizations to new implementations.

There are only a few requirements:

• Follow the style of the current implementations
• Use the default settings for the regex engine
• Update Dockerfile if it's necessary

Kudos

• Heng Li's for his work on Benchmark of Regex Libraries.
• A "challenge" on Madrid Devs group inspired me.
• Programming subreddit, helped me to improve the benchmark.

License

MIT © Mario Juárez.