RFR: 8311207: Optimization for j.u.UUID.toString

[Chen Liang]

On Sat, 1 Jul 2023 02:40:22 GMT, 温绍锦 <duke at openjdk.org> wrote:

>> [PR 14578 ](https://github.com/openjdk/jdk/pull/14578) still has unresolved discussions, continue to make improvements.
>> 
>> # Benchmark Result
>> 
>> 
>> sh make/devkit/createJMHBundle.sh
>> bash configure --with-jmh=build/jmh/jars
>> make test TEST="micro:java.util.UUIDBench.toString"
>> 
>> 
>> ## 1. [aliyun_ecs_c8i.xlarge](https://help.aliyun.com/document_detail/25378.html#c8i)
>> * cpu : intel xeon sapphire rapids (x64)
>> 
>> ``` diff
>> -Benchmark           (size)   Mode  Cnt   Score   Error   Units (baseline)
>> -UUIDBench.toString   20000  thrpt   15  62.019 ± 0.622  ops/us
>> 
>> +Benchmark           (size)   Mode  Cnt   Score   Error   Units
>> +UUIDBench.toString   20000  thrpt   15  82.998 ± 0.739  ops/us (+33.82%)
>> 
>> 
>> ## 2. [aliyun_ecs_c8a.xlarge](https://help.aliyun.com/document_detail/25378.html#c8a)
>> * cpu : amd epc genoa (x64)
>> 
>> ``` diff
>> -Benchmark           (size)   Mode  Cnt   Score   Error   Units (baseline)
>> -UUIDBench.toString   20000  thrpt   15  88.668 ± 0.672  ops/us
>> 
>> +Benchmark           (size)   Mode  Cnt   Score   Error   Units
>> +UUIDBench.toString   20000  thrpt   15  89.229 ± 0.271  ops/us (+0.63%)
>> 
>> 
>> 
>> ## 3. [aliyun_ecs_c8y.xlarge](https://help.aliyun.com/document_detail/25378.html#c8y)
>> * cpu : aliyun yitian 710 (aarch64)
>> ``` diff
>> -Benchmark           (size)   Mode  Cnt   Score   Error   Units (baseline)
>> -UUIDBench.toString   20000  thrpt   15  49.382 ± 2.160  ops/us
>> 
>> +Benchmark           (size)   Mode  Cnt   Score   Error   Units
>> +UUIDBench.toString   20000  thrpt   15  49.636 ± 1.974  ops/us (+0.51%)
>> 
>> 
>> ## 4. MacBookPro M1 Pro
>> ``` diff
>> -Benchmark           (size)   Mode  Cnt    Score   Error   Units (baseline)
>> -UUIDBench.toString   20000  thrpt   15  103.543 ± 0.963  ops/us
>> 
>> +Benchmark           (size)   Mode  Cnt    Score   Error   Units
>> +UUIDBench.toString   20000  thrpt   15  110.976 ± 0.685  ops/us (+7.17%)
>> 
>> 
>> ## 5. Orange Pi 5 Plus
>> 
>> ``` diff
>> -Benchmark           (size)   Mode  Cnt   Score   Error   Units (baseline)
>> -UUIDBench.toString   20000  thrpt   15  33.532 ± 0.396  ops/us
>> 
>> +Benchmark           (size)   Mode  Cnt   Score   Error   Units (PR)
>> +UUIDBench.toString   20000  thrpt   15  33.054 ± 0.190  ops/us (-4.42%)
>
> ![image](https://github.com/openjdk/jdk/assets/1166785/38c75145-b685-4c4e-a53a-97f8c44778e3)
> 
> it's enabled

> > @wenshao I have made my suggestions into a patch for you: [wenshao#1](https://github.com/wenshao/jdk/pull/1) Feel free to review.
> 
> your version performance is a bit worse, if i can't find the reason, I will restore the previous version

Can you post the benchmark results? And do you have like a baseline for the benchmarks, as there may be other factors that affect performance from run to run?

Also, my fault for actions: can you go to your actions tab and enable actions for your fork like this?
<img width="1267" alt="image" src="https://github.com/openjdk/jdk/assets/7806504/d049d88e-e4fc-4d35-b2a4-87fbfe82dbd5">

-------------

PR Comment: https://git.openjdk.org/jdk/pull/14745#issuecomment-1615401266