$ mvn clean install
$ (cd benchmarks/; java -jar target/benchmarks.jar)New Dell desktop
Benchmark Mode Cnt Score Error Units
ConfigServerBenchmark.devtoolsRestart avgt 10 1.034 ± 0.201 s/op
ConfigServerBenchmark.explodedJarMain avgt 10 3.271 ± 0.234 s/op
ConfigServerBenchmark.fatJar138 avgt 10 3.267 ± 0.173 s/op
ConfigServerBenchmark.fatJar142 avgt 10 3.423 ± 0.160 s/op
PetclinicBenchmark.noverify avgt 10 5.942 ± 0.300 s/op
PetclinicBenchmark.fatJar avgt 10 6.641 ± 0.248 s/op
PetclinicBenchmark.basicThin avgt 10 6.007 ± 0.359 s/op
PetclinicBenchmark.devtoolsRestart avgt 10 1.437 ± 0.226 s/op
SpringBoot138Benchmark.explodedJarLauncher avgt 10 2.832 ± 0.099 s/op
SpringBoot138Benchmark.explodedJarMain avgt 10 2.241 ± 0.158 s/op
SpringBoot138Benchmark.fatJar avgt 10 2.761 ± 0.200 s/op
SpringBoot142Benchmark.explodedJarLauncher avgt 10 3.018 ± 0.136 s/op
SpringBoot142Benchmark.explodedJarMain avgt 10 2.277 ± 0.124 s/op
SpringBoot142Benchmark.fatJar avgt 10 2.814 ± 0.088 s/op
SpringBootThinBenchmark.basic138Thin avgt 10 2.550 ± 0.115 s/op
SpringBootThinBenchmark.basic142Thin avgt 10 2.783 ± 0.129 s/op>5 year old Dell desktop
Benchmark Mode Cnt Score Error Units
ConfigServerBenchmark.devtoolsRestart avgt 10 2.041 ± 0.173 s/op
ConfigServerBenchmark.explodedJarMain avgt 10 6.930 ± 0.228 s/op
ConfigServerBenchmark.fatJar138 avgt 10 7.395 ± 0.203 s/op
ConfigServerBenchmark.fatJar142 avgt 10 7.439 ± 0.247 s/op
PetclinicBenchmark.devtoolsRestart avgt 10 2.868 ± 0.195 s/op
PetclinicBenchmark.fatJar avgt 10 13.579 ± 0.222 s/op
PetclinicBenchmark.noverify avgt 10 12.186 ± 0.373 s/op
SpringBoot138Benchmark.explodedJarLauncher avgt 10 5.821 ± 0.191 s/op
SpringBoot138Benchmark.explodedJarMain avgt 10 4.365 ± 0.117 s/op
SpringBoot138Benchmark.fatJar avgt 10 5.550 ± 0.132 s/op
SpringBoot142Benchmark.explodedJarLauncher avgt 10 6.238 ± 0.225 s/op
SpringBoot142Benchmark.explodedJarMain avgt 10 4.840 ± 0.137 s/op
SpringBoot142Benchmark.fatJar avgt 10 6.238 ± 0.560 s/op
SpringBootThinBenchmark.basic138Thin avgt 10 5.248 ± 0.130 s/op
SpringBootThinBenchmark.basic142Thin avgt 10 5.715 ± 0.115 s/opOne year old Lenovo X1 laptop.
Benchmark Mode Cnt Score Error Units
ConfigServerBenchmark.devtoolsRestart avgt 10 6.007 ± 0.313 s/op
ConfigServerBenchmark.explodedJarMain avgt 10 5.217 ± 0.280 s/op
ConfigServerBenchmark.fatJar138 avgt 10 5.651 ± 0.221 s/op
ConfigServerBenchmark.fatJar142 avgt 10 5.812 ± 0.163 s/op
PetclinicBenchmark.devtoolsRestart avgt 10 6.670 ± 0.260 s/op
PetclinicBenchmark.fatJar avgt 10 9.973 ± 0.637 s/op
PetclinicBenchmark.noverify avgt 10 9.312 ± 0.350 s/op
SpringBoot138Benchmark.explodedJarLauncher avgt 10 4.696 ± 0.242 s/op
SpringBoot138Benchmark.explodedJarMain avgt 10 3.599 ± 0.192 s/op
SpringBoot138Benchmark.fatJar avgt 10 4.427 ± 0.249 s/op
SpringBoot142Benchmark.explodedJarLauncher avgt 10 4.926 ± 0.313 s/op
SpringBoot142Benchmark.explodedJarMain avgt 10 3.824 ± 0.150 s/op
SpringBoot142Benchmark.fatJar avgt 10 4.814 ± 0.199 s/op
SpringBootThinBenchmark.basic138Thin avgt 10 4.370 ± 0.200 s/op
SpringBootThinBenchmark.basic142Thin avgt 10 4.796 ± 0.165 s/opSlightly knackered old Lenovo X220 laptop.
Benchmark Mode Cnt Score Error Units
ConfigServerBenchmark.devtoolsRestart avgt 10 6.242 ± 0.232 s/op
ConfigServerBenchmark.fatJar138 avgt 10 6.267 ± 0.274 s/op
ConfigServerBenchmark.fatJar142 avgt 10 6.426 ± 0.398 s/op
ConfigServerBenchmark.explodedJarMain avgt 10 5.880 ± 0.326 s/op
PetclinicBenchmark.devtoolsRestart avgt 10 6.910 ± 0.293 s/op
PetclinicBenchmark.fatJar avgt 10 11.241 ± 0.365 s/op
PetclinicBenchmark.noverify avgt 10 10.726 ± 0.526 s/op
SpringBoot138Benchmark.explodedJarLauncher avgt 10 5.526 ± 0.341 s/op
SpringBoot138Benchmark.explodedJarMain avgt 10 4.190 ± 0.201 s/op
SpringBoot138Benchmark.fatJar avgt 10 5.325 ± 0.206 s/op
SpringBoot142Benchmark.explodedJarLauncher avgt 10 5.958 ± 0.190 s/op
SpringBoot142Benchmark.explodedJarMain avgt 10 4.589 ± 0.258 s/op
SpringBoot142Benchmark.fatJar avgt 10 5.638 ± 0.269 s/op
SpringBootThinBenchmark.basic138Thin avgt 10 5.082 ± 0.307 s/op
SpringBootThinBenchmark.basic142Thin avgt 10 5.731 ± 0.211 s/opThere’s a tool in the JDK called jcmd that prints out a load of useful stuff
about a running process. E.g:
$ jcmd <PID> PerfCounter.printwhere <PID> is the process id. The petclinic (on "tower") has these
times in ns (highlights):
...
sun.classloader.findClassTime=2051631382
sun.classloader.parentDelegationTime=220795236
sun.cls.appClassLoadTime=2315218900
sun.cls.classInitTime=1058084598
sun.cls.classLinkedTime=1142874583
sun.cls.classVerifyTime=1037315846
sun.cls.defineAppClassTime=946831715
sun.cls.lookupSysClassTime=28253463
sun.cls.parseClassTime=1055187254
sun.cls.sharedClassLoadTime=581133
sun.cls.sysClassLoadTime=223416957
sun.urlClassLoader.readClassBytesTime=299665148
...So you can immediately save up to a second by using -noverify
(probably not advisable in production, but the jury is out on
that). The benchmark results confirm this the saving is actually only
700ms, but that’s a start.
Other things that stick out are
-
findClassTime- time spent working out where the damn things are, loading the bytes, parsing the bytes and defining them to build Class instances (2052ms). -
readClassBytesTime- time from when you have a reference to where the bytes are to the time you have read them in (300ms).
Also interesting (not shown above) is java.cls.loadedClasses, at
10660. Perhaps this is over optimistic but maybe some chunk of them is
being touched by accident that aren’t necessary and they can be
skipped, or deferred.