On Thu, 22 Jun 2023 00:13:06 GMT, 温绍锦 <d...@openjdk.org> wrote:
>> By optimizing the implementation of java.lang.Long#fastUUID, the performance
>> of the java.util.UUID#toString method can be significantly improved.
>>
>> The following are the test results of JMH:
>>
>> Benchmark Mode Cnt Score Error Units
>> UUIDUtilsBenchmark.new thrpt 5 92676.550 ± 292.213 ops/ms
>> UUIDUtilsBenchmark.original thrpt 5 37040.165 ± 1023.532 ops/ms
>
> 温绍锦 has updated the pull request incrementally with one additional commit
> since the last revision:
>
> move HEX256 to LongCache
I've tested the benchmarks and the patch and baseline (with extra stable
annotation) with a slightly varied version suitable for gradle run:
package com.alibaba.openjdk;
import org.openjdk.jmh.annotations.Benchmark;
import org.openjdk.jmh.annotations.BenchmarkMode;
import org.openjdk.jmh.annotations.Fork;
import org.openjdk.jmh.annotations.Measurement;
import org.openjdk.jmh.annotations.Mode;
import org.openjdk.jmh.annotations.OutputTimeUnit;
import org.openjdk.jmh.annotations.Warmup;
import org.openjdk.jmh.infra.Blackhole;
import java.util.UUID;
import java.util.concurrent.TimeUnit;
@BenchmarkMode(Mode.Throughput)
@OutputTimeUnit(TimeUnit.MILLISECONDS)
@Warmup(iterations = 3, time = 10)
@Measurement(iterations = 6, time = 5)
@Fork(1)
public class UUIDUtilsBenchmark {
public static UUID uuid = UUID.randomUUID();
@Benchmark
public void jdk(Blackhole bh) {
bh.consume(uuid.toString());
}
@Benchmark
public void fast(Blackhole bh) {
bh.consume(UUIDUtils.fastUUID(uuid));
}
}
The throughput varies a lot between iterations somehow; the patch and baseline
with stable has no significant difference (i.e. within the error range, about
10%)
-------------
PR Comment: https://git.openjdk.org/jdk/pull/14578#issuecomment-1601953110
