python (12.9k questions)

javascript (9.2k questions)

reactjs (4.7k questions)

java (4.2k questions)

java (4.2k questions)

c# (3.5k questions)

c# (3.5k questions)

html (3.3k questions)

Questions - jmh

How exactly does JMH do the calculations?Where in the code or in which file can you see the process and formula for calculating "score" and "error"?

How exactly does JMH do the calculations? Where in the code or in which file can you see the process and formula for calculating "score" and "error"? CopyOnWriteBenchmark.testAdd ...
test-img

ТудыСюды

java

java-8

benchmarking

jmh

Votes: 0

Answers: 1

Latest Answer

looking into debugger I see that the code responsible for calculations is generated at compilation time separately for each benchmark. Below there is an example of generated method: public static void...
test-img

Sergey Tsypanov

Why does running multiple lambdas in loops suddenly slow down?

Consider the following code: public class Playground { private static final int MAX = 100_000_000; public static void main(String... args) { execute(() -> {}); execute(() ...
test-img

Jakes

java

performance

jit

jmh

Votes: 0

Answers: 1

Latest Answer

You can actually replicate this with JMH SingleShot mode: @BenchmarkMode(Mode.SingleShotTime) @Warmup(iterations = 0) @Measurement(iterations = 1) @Fork(1) public class Lambdas { @Benchmark p...
test-img

Aleksey Shipilev

looping over array, performance difference between indexed and enhanced for loop

The JLS states, that for arrays, "The enhanced for statement is equivalent to a basic for statement of the form". However if I check the generated bytecode for JDK8, for both variants differ...
test-img

Martin Mucha

java

jmh

Votes: 0

Answers: 1

Latest Answer

TL;DR: You are observing what happens when JIT compiler cannot trust that values are not changing inside the loop. Additionally, in the tiny benchmark like this, Blackhole.consume costs dominate, obsc...
test-img

Aleksey Shipilev

Posts

Questions

Blogs

Jobs