Re: RFR: 8285519: Change usages of TimeUnit.convert to TimeUnit.toXXX [v2]
On Sun, 15 May 2022 10:31:20 GMT, Andrey Turbanov wrote:
>> TimeUnit.toMillis/toNanos/toMicros/toSeconds is shorter and a bit faster.
>> Compared via JMH benchmark: 150ns -> 125ns/op
>>
>> Benchamark adapted from
>> http://cr.openjdk.java.net/~shade/8152083/TimeUnitBench.java
>>
>>
>> @Warmup(iterations = 5, time = 1, timeUnit = TimeUnit.SECONDS)
>> @Measurement(iterations = 5, time = 1, timeUnit = TimeUnit.SECONDS)
>> @Fork(1)
>> @State(Scope.Thread)
>> @BenchmarkMode(Mode.AverageTime)
>> @OutputTimeUnit(TimeUnit.NANOSECONDS)
>> public class TimeUnitBench {
>>
>> static final int SIZE = TimeUnit.values().length * 10;
>>
>> @Param({"0", "1", "2", "3", "4", "5", "6", "-1"})
>> int bias;
>>
>> TimeUnit[] mod;
>>
>> @Setup
>> public void setup() {
>> mod = new TimeUnit[SIZE];
>>
>> TimeUnit[] vals = TimeUnit.values();
>> for (int c = 0; c < SIZE; c++) {
>> if (bias == -1) {
>> // megamorphic
>> mod[c] = vals[c % vals.length];
>> } else {
>> mod[c] = vals[bias];
>> }
>> }
>>
>> Random r = new Random();
>> for (int c = 0; c < 1; c++) {
>> int i = r.nextInt();
>> for (int o = 0; o < vals.length; o++) {
>> if (vals[o].toNanos(i) != TimeUnit.NANOSECONDS.convert(i,
>> vals[o]))
>> throw new IllegalStateException("switch " + o);
>> }
>> }
>> }
>>
>> @Benchmark
>> public void const_convert(Blackhole bh) {
>> for (TimeUnit tu : mod) {
>> bh.consume(do_convert(tu));
>> }
>> }
>>
>> @Benchmark
>> public void value_convert(Blackhole bh) {
>> for (TimeUnit tu : mod) {
>> bh.consume(do_convert(tu, 1L));
>> }
>> }
>>
>> @Benchmark
>> public void const_toNanos(Blackhole bh) {
>> for (TimeUnit tu : mod) {
>> bh.consume(do_toNanos(tu));
>> }
>> }
>>
>> @Benchmark
>> public void value_toNanos(Blackhole bh) {
>> for (TimeUnit tu : mod) {
>> bh.consume(do_toNanos(tu, 1L));
>> }
>> }
>>
>> @CompilerControl(CompilerControl.Mode.DONT_INLINE)
>> private long do_toNanos(TimeUnit tu) {
>> return tu.toNanos(1L);
>> }
>>
>> @CompilerControl(CompilerControl.Mode.DONT_INLINE)
>> private long do_toNanos(TimeUnit tu, long value) {
>> return tu.toNanos(value);
>> }
>>
>> @CompilerControl(CompilerControl.Mode.DONT_INLINE)
>> private long do_convert(TimeUnit tu) {
>> return TimeUnit.NANOSECONDS.convert(1L, tu);
>> }
>>
>> @CompilerControl(CompilerControl.Mode.DONT_INLINE)
>> private long do_convert(TimeUnit tu, long value) {
>> return TimeUnit.NANOSECONDS.convert(value, tu);
>> }
>> }
>>
>> Results:
>>
>> Benchmark(bias) Mode CntScoreError Units
>> TimeUnitBench.const_convert 0 avgt5 151,856 ± 28,595 ns/op
>> TimeUnitBench.const_convert 1 avgt5 150,720 ± 23,863 ns/op
>> TimeUnitBench.const_convert 2 avgt5 151,432 ± 23,184 ns/op
>> TimeUnitBench.const_convert 3 avgt5 150,959 ± 24,726 ns/op
>> TimeUnitBench.const_convert 4 avgt5 150,966 ± 25,280 ns/op
>> TimeUnitBench.const_convert 5 avgt5 150,976 ± 25,542 ns/op
>> TimeUnitBench.const_convert 6 avgt5 151,118 ± 25,254 ns/op
>> TimeUnitBench.const_convert -1 avgt5 152,673 ± 29,861 ns/op
>> TimeUnitBench.const_toNanos 0 avgt5 121,296 ± 25,236 ns/op
>> TimeUnitBench.const_toNanos 1 avgt5 121,707 ± 25,364 ns/op
>> TimeUnitBench.const_toNanos 2 avgt5 121,736 ± 25,726 ns/op
>> TimeUnitBench.const_toNanos 3 avgt5 121,822 ± 25,491 ns/op
>> TimeUnitBench.const_toNanos 4 avgt5 121,867 ± 26,090 ns/op
>> TimeUnitBench.const_toNanos 5 avgt5 121,927 ± 25,611 ns/op
>> TimeUnitBench.const_toNanos 6 avgt5 121,821 ± 25,843 ns/op
>> TimeUnitBench.const_toNanos -1 avgt5 121,923 ± 25,206 ns/op
>> TimeUnitBench.value_convert 0 avgt5 150,525 ± 25,439 ns/op
>> TimeUnitBench.value_convert 1 avgt5 151,098 ± 24,024 ns/op
>> TimeUnitBench.value_convert 2 avgt5 151,259 ± 25,381 ns/op
>> TimeUnitBench.value_convert 3 avgt5 151,030 ± 25,548 ns/op
>> TimeUnitBench.value_convert 4 avgt5 151,290 ± 25,998 ns/op
>> TimeUnitBench.value_convert 5 avgt5 151,006 ± 25,448 ns/op
>> TimeUnitBench.value_convert 6 avgt5 150,945 ± 25,314 ns/op
>> TimeUnitBench.value_convert -1 avgt5 151,186 ± 25,814 ns/op
>> TimeUnitBench.value_toNanos 0 avgt5 121,556 ± 25,745 ns/op
>> TimeUnitBench.value_toNanos 1 avgt5 123,410 ± 22,323 ns/op
>> TimeUnitBench.value_toNanos 2 avgt5 125,452
Re: RFR: 8285519: Change usages of TimeUnit.convert to TimeUnit.toXXX [v2]
> TimeUnit.toMillis/toNanos/toMicros/toSeconds is shorter and a bit faster.
> Compared via JMH benchmark: 150ns -> 125ns/op
>
> Benchamark adapted from
> http://cr.openjdk.java.net/~shade/8152083/TimeUnitBench.java
>
>
> @Warmup(iterations = 5, time = 1, timeUnit = TimeUnit.SECONDS)
> @Measurement(iterations = 5, time = 1, timeUnit = TimeUnit.SECONDS)
> @Fork(1)
> @State(Scope.Thread)
> @BenchmarkMode(Mode.AverageTime)
> @OutputTimeUnit(TimeUnit.NANOSECONDS)
> public class TimeUnitBench {
>
> static final int SIZE = TimeUnit.values().length * 10;
>
> @Param({"0", "1", "2", "3", "4", "5", "6", "-1"})
> int bias;
>
> TimeUnit[] mod;
>
> @Setup
> public void setup() {
> mod = new TimeUnit[SIZE];
>
> TimeUnit[] vals = TimeUnit.values();
> for (int c = 0; c < SIZE; c++) {
> if (bias == -1) {
> // megamorphic
> mod[c] = vals[c % vals.length];
> } else {
> mod[c] = vals[bias];
> }
> }
>
> Random r = new Random();
> for (int c = 0; c < 1; c++) {
> int i = r.nextInt();
> for (int o = 0; o < vals.length; o++) {
> if (vals[o].toNanos(i) != TimeUnit.NANOSECONDS.convert(i,
> vals[o]))
> throw new IllegalStateException("switch " + o);
> }
> }
> }
>
> @Benchmark
> public void const_convert(Blackhole bh) {
> for (TimeUnit tu : mod) {
> bh.consume(do_convert(tu));
> }
> }
>
> @Benchmark
> public void value_convert(Blackhole bh) {
> for (TimeUnit tu : mod) {
> bh.consume(do_convert(tu, 1L));
> }
> }
>
> @Benchmark
> public void const_toNanos(Blackhole bh) {
> for (TimeUnit tu : mod) {
> bh.consume(do_toNanos(tu));
> }
> }
>
> @Benchmark
> public void value_toNanos(Blackhole bh) {
> for (TimeUnit tu : mod) {
> bh.consume(do_toNanos(tu, 1L));
> }
> }
>
> @CompilerControl(CompilerControl.Mode.DONT_INLINE)
> private long do_toNanos(TimeUnit tu) {
> return tu.toNanos(1L);
> }
>
> @CompilerControl(CompilerControl.Mode.DONT_INLINE)
> private long do_toNanos(TimeUnit tu, long value) {
> return tu.toNanos(value);
> }
>
> @CompilerControl(CompilerControl.Mode.DONT_INLINE)
> private long do_convert(TimeUnit tu) {
> return TimeUnit.NANOSECONDS.convert(1L, tu);
> }
>
> @CompilerControl(CompilerControl.Mode.DONT_INLINE)
> private long do_convert(TimeUnit tu, long value) {
> return TimeUnit.NANOSECONDS.convert(value, tu);
> }
> }
>
> Results:
>
> Benchmark(bias) Mode CntScoreError Units
> TimeUnitBench.const_convert 0 avgt5 151,856 ± 28,595 ns/op
> TimeUnitBench.const_convert 1 avgt5 150,720 ± 23,863 ns/op
> TimeUnitBench.const_convert 2 avgt5 151,432 ± 23,184 ns/op
> TimeUnitBench.const_convert 3 avgt5 150,959 ± 24,726 ns/op
> TimeUnitBench.const_convert 4 avgt5 150,966 ± 25,280 ns/op
> TimeUnitBench.const_convert 5 avgt5 150,976 ± 25,542 ns/op
> TimeUnitBench.const_convert 6 avgt5 151,118 ± 25,254 ns/op
> TimeUnitBench.const_convert -1 avgt5 152,673 ± 29,861 ns/op
> TimeUnitBench.const_toNanos 0 avgt5 121,296 ± 25,236 ns/op
> TimeUnitBench.const_toNanos 1 avgt5 121,707 ± 25,364 ns/op
> TimeUnitBench.const_toNanos 2 avgt5 121,736 ± 25,726 ns/op
> TimeUnitBench.const_toNanos 3 avgt5 121,822 ± 25,491 ns/op
> TimeUnitBench.const_toNanos 4 avgt5 121,867 ± 26,090 ns/op
> TimeUnitBench.const_toNanos 5 avgt5 121,927 ± 25,611 ns/op
> TimeUnitBench.const_toNanos 6 avgt5 121,821 ± 25,843 ns/op
> TimeUnitBench.const_toNanos -1 avgt5 121,923 ± 25,206 ns/op
> TimeUnitBench.value_convert 0 avgt5 150,525 ± 25,439 ns/op
> TimeUnitBench.value_convert 1 avgt5 151,098 ± 24,024 ns/op
> TimeUnitBench.value_convert 2 avgt5 151,259 ± 25,381 ns/op
> TimeUnitBench.value_convert 3 avgt5 151,030 ± 25,548 ns/op
> TimeUnitBench.value_convert 4 avgt5 151,290 ± 25,998 ns/op
> TimeUnitBench.value_convert 5 avgt5 151,006 ± 25,448 ns/op
> TimeUnitBench.value_convert 6 avgt5 150,945 ± 25,314 ns/op
> TimeUnitBench.value_convert -1 avgt5 151,186 ± 25,814 ns/op
> TimeUnitBench.value_toNanos 0 avgt5 121,556 ± 25,745 ns/op
> TimeUnitBench.value_toNanos 1 avgt5 123,410 ± 22,323 ns/op
> TimeUnitBench.value_toNanos 2 avgt5 125,452 ± 26,575 ns/op
> TimeUnitBench.value_toNanos 3 avgt5 125,297 ± 26,204 ns/op
> TimeUnitBench.value_toNanos 4 avgt5 125,357 ± 26,085 ns/op
>
