This project uses Code Tools: jmh to bench many regex library for java, and try to defined the fastest way to run them.
It uses ideas and code from Java Regular expression library benchmarks and Java regular expression library benchmarks – 2015. It adds some new libraries.
The joni library works on byte[] instead of a String, so I also bench different way to extract that from a String, to get the fastest. But each variation is test with joni to ensure that's it's really usefull.
Grok is a thick wrapper around java's regex, inspired by logstash.
To run it:
mvn clean package site && java -jar target/regexperf.jar
Options -f allows to make a quick run, to check code. Benchmark's name to run can be given at the commande line.
The maven reports include a version check, to ensure that all the regexes uses the latest versions.
First a test with the latest Java 8 (1.8.0_152)
$ lscpu
CPU(s): 8
Model name: Intel Xeon E312xx (Sandy Bridge)
CPU MHz: 2593.748
# JMH version: 1.19
# VM version: JDK 1.8.0_152, VM 25.152-b16
# VM invoker: /usr/java/jdk1.8.0_152/jre/bin/java
# VM options: <none>
# Warmup: 5 iterations, 1 s each
# Measurement: 10 iterations, 30 s each
# Timeout: 88 s per iteration
# Threads: 3 threads, will synchronize iterations
Benchmark Mode Cnt Score Error Units
RegexPerf.big_org_joni_ascii_reuse avgt 10 132.353 ± 0.903 us/op
RegexPerf.big_java_util_regex avgt 10 14222.734 ± 49.692 us/op
RegexPerf.big_io_thekraken_grok_api avgt 10 14566.463 ± 79.139 us/op
RegexPerf.jregex avgt 10 14.245 ± 0.068 us/op
RegexPerf.org_joni_ascii_unsafe avgt 10 18.225 ± 1.214 us/op
RegexPerf.org_joni_ascii_reuse avgt 10 18.694 ± 1.692 us/op
RegexPerf.org_joni_ascii avgt 10 19.061 ± 2.007 us/op
RegexPerf.org_joni avgt 10 22.776 ± 4.679 us/op
RegexPerf.java_util_regex avgt 10 58.757 ± 0.391 us/op
RegexPerf.io_thekraken_grok_api avgt 10 64.270 ± 0.634 us/op
RegexPerf.org_apache_xerces_impl_xpath_regex_RegularExpression avgt 10 150.605 ± 1.434 us/op
RegexPerf.gnu_regexp avgt 10 220.395 ± 2.042 us/op
StringToBytes.getBytesAsciiUnsafe avgt 10 22.972 ± 0.225 ns/op
StringToBytes.getBytesAsciiReuse avgt 10 33.220 ± 0.229 ns/op
StringToBytes.byCharset_US_ASCII avgt 10 39.574 ± 0.181 ns/op
StringToBytes.getBytesAscii avgt 10 43.377 ± 0.213 ns/op
StringToBytes.getBytesUTF16LE avgt 10 60.789 ± 0.584 ns/op
StringToBytes.byName_US_ASCII avgt 10 61.946 ± 0.555 ns/op
StringToBytes.byName_UTF_8 avgt 10 69.874 ± 0.636 ns/op
StringToBytes.byCharset_UTF_8 avgt 10 78.423 ± 0.396 ns/op
StringToBytes.byName_UTF_16 avgt 10 131.655 ± 1.696 ns/op
StringToBytes.byCharsetEncoder_US_ASCII avgt 10 266.363 ± 16.720 ns/op
StringToBytes.byCharset_UTF_16 avgt 10 328.958 ± 5.447 ns/op
And one with 9 (9.0.1)
# JMH version: 1.19
# VM version: JDK 9.0.1, VM 9.0.1+11
# VM invoker: /usr/java/jdk-9.0.1/bin/java
# VM options: <none>
# Warmup: 5 iterations, 1 s each
# Measurement: 10 iterations, 30 s each
# Timeout: 88 s per iteration
# Threads: 3 threads, will synchronize iterations
Benchmark Mode Cnt Score Error Units
RegexPerf.big_org_joni_ascii_reuse avgt 10 128.855 ± 1.509 us/op
RegexPerf.big_io_thekraken_grok_api avgt 10 9247.838 ± 172.971 us/op
RegexPerf.big_java_util_regex avgt 10 9255.848 ± 249.751 us/op
RegexPerf.jregex avgt 10 13.634 ± 0.187 us/op
RegexPerf.org_joni_ascii avgt 10 20.653 ± 1.148 us/op
RegexPerf.org_joni_ascii_reuse avgt 10 21.571 ± 0.850 us/op
RegexPerf.org_joni avgt 10 23.943 ± 0.524 us/op
RegexPerf.java_util_regex avgt 10 37.995 ± 0.756 us/op
RegexPerf.io_thekraken_grok_api avgt 10 44.095 ± 0.957 us/op
RegexPerf.org_apache_xerces_impl_xpath_regex_RegularExpression avgt 10 121.135 ± 1.173 us/op
RegexPerf.gnu_regexp avgt 10 171.659 ± 2.666 us/op
StringToBytes.byCharset_US_ASCII avgt 10 29.405 ± 0.280 ns/op
StringToBytes.getBytesAsciiReuse avgt 10 32.157 ± 0.302 ns/op
StringToBytes.byName_US_ASCII avgt 10 36.610 ± 0.487 ns/op
StringToBytes.getBytesAscii avgt 10 40.438 ± 0.412 ns/op
StringToBytes.byCharset_UTF_8 avgt 10 50.512 ± 0.591 ns/op
StringToBytes.byName_UTF_8 avgt 10 58.353 ± 0.909 ns/op
StringToBytes.getBytesUTF16LE avgt 10 59.463 ± 0.724 ns/op
StringToBytes.byCharsetEncoder_US_ASCII avgt 10 90.954 ± 1.782 ns/op
StringToBytes.byName_UTF_16 avgt 10 120.022 ± 1.346 ns/op
StringToBytes.byCharset_UTF_16 avgt 10 379.761 ± 4.262 ns/op
The unsafe benchmarks are gone, as the internal structure of String changed in java 9.