Performance impact of instanceof test for interfaces

interface_benchmark_result.txt

===============================
   BENCHMARK CODE
===============================

package grondag.benchmark;

import java.util.Random;

import org.openjdk.jmh.annotations.Benchmark;

public class InterfaceChecks {

    public static interface Consistent {
        boolean hasValue();
        
        int getValue();
    }
    
    public static interface Inconsistent {
        int getValue();
    }
    
    // ensure we have a non-simple type hierarchy
    public static interface NoiseA { }
    public static interface NoiseB { }
    public static interface NoiseC { }
    public static interface NoiseD { }
    public static interface NoiseE { }
    
    public static class Missing implements Consistent, NoiseA, NoiseB, NoiseC, NoiseD, NoiseE {
        @Override
        public boolean hasValue() {
            return false;
        }

        @Override
        public int getValue() {
            return 0;
        }
    }
    
    public static class Present implements Consistent, Inconsistent, NoiseA, NoiseB, NoiseC, NoiseD, NoiseE {
        final int value;
        
        Present(int value) {
            this.value = value;
        }
        
        @Override
        public boolean hasValue() {
            return true;
        }

        @Override
        public int getValue() {
            return value;
        }
    }
    static final int SAMPLE_COUNT = 1000;
    
    static final Object[] subjects = new Object[SAMPLE_COUNT];
    
    static {
        Random r = new Random();
        for(int i = 0; i < SAMPLE_COUNT; i++) {
            subjects[i] = r.nextBoolean() ? new Missing() : new Present(r.nextInt(0xFFFF));
        }
    }
    
    @Benchmark
    public void testConsistent() {
        int tally = 0;
        for(Object o : subjects) {
            Consistent c = (Consistent)o;
            if(c.hasValue())
                tally += c.getValue();
        }
    }

    @Benchmark
    public void testInconsistent() {
        int tally = 0;
        for(Object o : subjects) {
            if(o instanceof Inconsistent) {
                tally +=  ((Inconsistent)o).getValue();
            }
        }
    }
    
    @Benchmark
    public void testClass() {
        int tally = 0;
        for(Object o : subjects) {
            if(o instanceof Present) {
                tally +=  ((Present)o).getValue();
            }
        }
    }
}


===============================
   SUMMARY OF RESULTS
===============================

Benchmark                          Mode  Cnt        Score       Error  Units
InterfaceChecks.testClass         thrpt   25  1440402.994 ± 44639.119  ops/s
InterfaceChecks.testConsistent    thrpt   25   920190.584 ± 17427.822  ops/s
InterfaceChecks.testInconsistent  thrpt   25    78355.346 ±  1891.421  ops/s

===============================
   FULL JMH LOG BELOW
===============================

# JMH version: 1.21
# VM version: JDK 1.8.0_191, Java HotSpot(TM) 64-Bit Server VM, 25.191-b12
# VM invoker: /Library/Java/JavaVirtualMachines/jdk1.8.0_191.jdk/Contents/Home/jre/bin/java
# VM options: <none>
# Warmup: 5 iterations, 10 s each
# Measurement: 5 iterations, 10 s each
# Timeout: 10 min per iteration
# Threads: 1 thread, will synchronize iterations
# Benchmark mode: Throughput, ops/time
# Benchmark: grondag.benchmark.InterfaceChecks.testClass

# Run progress: 0.00% complete, ETA 00:25:00
# Fork: 1 of 5
# Warmup Iteration   1: 1630623.845 ops/s
# Warmup Iteration   2: 1630506.649 ops/s
# Warmup Iteration   3: 1463384.640 ops/s
# Warmup Iteration   4: 1466727.271 ops/s
# Warmup Iteration   5: 1450841.079 ops/s
Iteration   1: 1455519.482 ops/s
Iteration   2: 1449128.299 ops/s
Iteration   3: 1414315.659 ops/s
Iteration   4: 1397652.587 ops/s
Iteration   5: 1348696.743 ops/s

# Run progress: 6.67% complete, ETA 00:23:27
# Fork: 2 of 5
# Warmup Iteration   1: 1582942.646 ops/s
# Warmup Iteration   2: 1631141.987 ops/s
# Warmup Iteration   3: 1494150.366 ops/s
# Warmup Iteration   4: 1511661.779 ops/s
# Warmup Iteration   5: 1512708.516 ops/s
Iteration   1: 1514950.888 ops/s
Iteration   2: 1507328.824 ops/s
Iteration   3: 1511371.008 ops/s
Iteration   4: 1509914.020 ops/s
Iteration   5: 1498794.563 ops/s

# Run progress: 13.33% complete, ETA 00:21:45
# Fork: 3 of 5
# Warmup Iteration   1: 1697489.017 ops/s
# Warmup Iteration   2: 1692034.364 ops/s
# Warmup Iteration   3: 1483670.314 ops/s
# Warmup Iteration   4: 1487860.956 ops/s
# Warmup Iteration   5: 1481181.576 ops/s
Iteration   1: 1485592.989 ops/s
Iteration   2: 1486233.110 ops/s
Iteration   3: 1443420.813 ops/s
Iteration   4: 1416856.214 ops/s
Iteration   5: 1362707.983 ops/s

# Run progress: 20.00% complete, ETA 00:20:05
# Fork: 4 of 5
# Warmup Iteration   1: 1494000.800 ops/s
# Warmup Iteration   2: 1649594.026 ops/s
# Warmup Iteration   3: 1452761.885 ops/s
# Warmup Iteration   4: 1469149.768 ops/s
# Warmup Iteration   5: 1457864.766 ops/s
Iteration   1: 1460998.046 ops/s
Iteration   2: 1332771.586 ops/s
Iteration   3: 1368607.534 ops/s
Iteration   4: 1420231.827 ops/s
Iteration   5: 1480091.124 ops/s

# Run progress: 26.67% complete, ETA 00:18:24
# Fork: 5 of 5
# Warmup Iteration   1: 1681607.564 ops/s
# Warmup Iteration   2: 1636520.395 ops/s
# Warmup Iteration   3: 1480012.014 ops/s
# Warmup Iteration   4: 1493619.722 ops/s
# Warmup Iteration   5: 1479310.614 ops/s
Iteration   1: 1349769.994 ops/s
Iteration   2: 1357899.966 ops/s
Iteration   3: 1449685.790 ops/s
Iteration   4: 1493087.450 ops/s
Iteration   5: 1494448.359 ops/s


Result "grondag.benchmark.InterfaceChecks.testClass":
  1440402.994 ±(99.9%) 44639.119 ops/s [Average]
  (min, avg, max) = (1332771.586, 1440402.994, 1514950.888), stdev = 59591.947
  CI (99.9%): [1395763.875, 1485042.114] (assumes normal distribution)


# JMH version: 1.21
# VM version: JDK 1.8.0_191, Java HotSpot(TM) 64-Bit Server VM, 25.191-b12
# VM invoker: /Library/Java/JavaVirtualMachines/jdk1.8.0_191.jdk/Contents/Home/jre/bin/java
# VM options: <none>
# Warmup: 5 iterations, 10 s each
# Measurement: 5 iterations, 10 s each
# Timeout: 10 min per iteration
# Threads: 1 thread, will synchronize iterations
# Benchmark mode: Throughput, ops/time
# Benchmark: grondag.benchmark.InterfaceChecks.testConsistent

# Run progress: 33.33% complete, ETA 00:16:44
# Fork: 1 of 5
# Warmup Iteration   1: 785784.019 ops/s
# Warmup Iteration   2: 961959.554 ops/s
# Warmup Iteration   3: 910328.606 ops/s
# Warmup Iteration   4: 936844.036 ops/s
# Warmup Iteration   5: 929185.069 ops/s
Iteration   1: 954587.862 ops/s
Iteration   2: 954112.598 ops/s
Iteration   3: 934940.749 ops/s
Iteration   4: 958569.235 ops/s
Iteration   5: 933260.347 ops/s

# Run progress: 40.00% complete, ETA 00:15:03
# Fork: 2 of 5
# Warmup Iteration   1: 799685.606 ops/s
# Warmup Iteration   2: 1018425.443 ops/s
# Warmup Iteration   3: 910837.958 ops/s
# Warmup Iteration   4: 914433.033 ops/s
# Warmup Iteration   5: 885393.282 ops/s
Iteration   1: 925166.525 ops/s
Iteration   2: 941484.456 ops/s
Iteration   3: 915567.910 ops/s
Iteration   4: 897602.584 ops/s
Iteration   5: 877910.785 ops/s

# Run progress: 46.67% complete, ETA 00:13:23
# Fork: 3 of 5
# Warmup Iteration   1: 792533.813 ops/s
# Warmup Iteration   2: 975762.130 ops/s
# Warmup Iteration   3: 917601.223 ops/s
# Warmup Iteration   4: 930877.084 ops/s
# Warmup Iteration   5: 887446.064 ops/s
Iteration   1: 887397.975 ops/s
Iteration   2: 892959.569 ops/s
Iteration   3: 881490.220 ops/s
Iteration   4: 894520.778 ops/s
Iteration   5: 930129.628 ops/s

# Run progress: 53.33% complete, ETA 00:11:43
# Fork: 4 of 5
# Warmup Iteration   1: 786687.551 ops/s
# Warmup Iteration   2: 975318.591 ops/s
# Warmup Iteration   3: 917360.402 ops/s
# Warmup Iteration   4: 912161.473 ops/s
# Warmup Iteration   5: 918204.740 ops/s
Iteration   1: 949386.870 ops/s
Iteration   2: 945608.375 ops/s
Iteration   3: 913853.691 ops/s
Iteration   4: 912815.539 ops/s
Iteration   5: 929787.543 ops/s

# Run progress: 60.00% complete, ETA 00:10:02
# Fork: 5 of 5
# Warmup Iteration   1: 816396.098 ops/s
# Warmup Iteration   2: 998544.413 ops/s
# Warmup Iteration   3: 912174.150 ops/s
# Warmup Iteration   4: 897145.230 ops/s
# Warmup Iteration   5: 929744.199 ops/s
Iteration   1: 922648.826 ops/s
Iteration   2: 913931.579 ops/s
Iteration   3: 914993.451 ops/s
Iteration   4: 911513.370 ops/s
Iteration   5: 910524.140 ops/s


Result "grondag.benchmark.InterfaceChecks.testConsistent":
  920190.584 ±(99.9%) 17427.822 ops/s [Average]
  (min, avg, max) = (877910.785, 920190.584, 958569.235), stdev = 23265.643
  CI (99.9%): [902762.763, 937618.406] (assumes normal distribution)


# JMH version: 1.21
# VM version: JDK 1.8.0_191, Java HotSpot(TM) 64-Bit Server VM, 25.191-b12
# VM invoker: /Library/Java/JavaVirtualMachines/jdk1.8.0_191.jdk/Contents/Home/jre/bin/java
# VM options: <none>
# Warmup: 5 iterations, 10 s each
# Measurement: 5 iterations, 10 s each
# Timeout: 10 min per iteration
# Threads: 1 thread, will synchronize iterations
# Benchmark mode: Throughput, ops/time
# Benchmark: grondag.benchmark.InterfaceChecks.testInconsistent

# Run progress: 66.67% complete, ETA 00:08:22
# Fork: 1 of 5
# Warmup Iteration   1: 76825.050 ops/s
# Warmup Iteration   2: 75448.191 ops/s
# Warmup Iteration   3: 78273.791 ops/s
# Warmup Iteration   4: 78163.358 ops/s
# Warmup Iteration   5: 78116.222 ops/s
Iteration   1: 77684.022 ops/s
Iteration   2: 73743.157 ops/s
Iteration   3: 73493.509 ops/s
Iteration   4: 75701.889 ops/s
Iteration   5: 77700.863 ops/s

# Run progress: 73.33% complete, ETA 00:06:41
# Fork: 2 of 5
# Warmup Iteration   1: 78216.680 ops/s
# Warmup Iteration   2: 78991.639 ops/s
# Warmup Iteration   3: 80136.113 ops/s
# Warmup Iteration   4: 77828.156 ops/s
# Warmup Iteration   5: 75594.921 ops/s
Iteration   1: 75836.032 ops/s
Iteration   2: 75886.783 ops/s
Iteration   3: 77409.299 ops/s
Iteration   4: 75828.263 ops/s
Iteration   5: 77795.896 ops/s

# Run progress: 80.00% complete, ETA 00:05:01
# Fork: 3 of 5
# Warmup Iteration   1: 74828.381 ops/s
# Warmup Iteration   2: 72187.938 ops/s
# Warmup Iteration   3: 78361.617 ops/s
# Warmup Iteration   4: 77345.074 ops/s
# Warmup Iteration   5: 80323.474 ops/s
Iteration   1: 80022.827 ops/s
Iteration   2: 79502.978 ops/s
Iteration   3: 79895.515 ops/s
Iteration   4: 79713.714 ops/s
Iteration   5: 79193.585 ops/s

# Run progress: 86.67% complete, ETA 00:03:20
# Fork: 4 of 5
# Warmup Iteration   1: 79364.627 ops/s
# Warmup Iteration   2: 76557.442 ops/s
# Warmup Iteration   3: 77653.180 ops/s
# Warmup Iteration   4: 78363.582 ops/s
# Warmup Iteration   5: 78482.792 ops/s
Iteration   1: 78698.569 ops/s
Iteration   2: 80083.003 ops/s
Iteration   3: 77701.191 ops/s
Iteration   4: 80101.058 ops/s
Iteration   5: 81821.293 ops/s

# Run progress: 93.33% complete, ETA 00:01:40
# Fork: 5 of 5
# Warmup Iteration   1: 78067.797 ops/s
# Warmup Iteration   2: 77887.662 ops/s
# Warmup Iteration   3: 80283.382 ops/s
# Warmup Iteration   4: 79995.244 ops/s
# Warmup Iteration   5: 80370.876 ops/s
Iteration   1: 82932.753 ops/s
Iteration   2: 80309.037 ops/s
Iteration   3: 75878.677 ops/s
Iteration   4: 82964.102 ops/s
Iteration   5: 78985.625 ops/s


Result "grondag.benchmark.InterfaceChecks.testInconsistent":
  78355.346 ±(99.9%) 1891.421 ops/s [Average]
  (min, avg, max) = (73493.509, 78355.346, 82964.102), stdev = 2524.993
  CI (99.9%): [76463.925, 80246.767] (assumes normal distribution)


# Run complete. Total time: 00:25:05

REMEMBER: The numbers below are just data. To gain reusable insights, you need to follow up on
why the numbers are the way they are. Use profilers (see -prof, -lprof), design factorial
experiments, perform baseline and negative tests that provide experimental control, make sure
the benchmarking environment is safe on JVM/OS/HW level, ask for reviews from the domain experts.
Do not assume the numbers tell you what you want them to tell.

Benchmark                          Mode  Cnt        Score       Error  Units
InterfaceChecks.testClass         thrpt   25  1440402.994 ± 44639.119  ops/s
InterfaceChecks.testConsistent    thrpt   25   920190.584 ± 17427.822  ops/s
InterfaceChecks.testInconsistent  thrpt   25    78355.346 ±  1891.421  ops/s