RFR (S) CR 8016236: Class.getGenericInterfaces performance improvement

[Paul Sandoz]

On Jun 10, 2013, at 5:53 PM, Aleksey Shipilev <aleksey.shipilev at oracle.com> wrote:

> Hi,
> 
> This is the follow-up on the issue Doug identified:
>  http://mail.openjdk.java.net/pipermail/core-libs-dev/2013-June/017798.html
> 
> I had reworked the patch, webrev is here:
>  http://cr.openjdk.java.net/~shade/8016236/webrev.01/
> 
> Notable differences from Doug's version are:
>  - handle non-generic cases as well

I was wondering about that case too.


>  - reuse ReflectionData to cache the interfaces and generic signatures

Any guess on the size impact due to those new fields in ReflectionData?


>  - code style (chained ternary operators blown up)
>  - fixes the race along the way
>      http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=6398355
> 
> Testing:
>  - Linux x86_64/release: build OK
>  - Linux x86_64/release: java/lang/reflect regression tests OK
>  - Microbenchmarks show whooping increase in performance, see below
> 

Nice improvements.

Paul.


> (If there are no stylistic and other comments, I would like to do the
> JPRT submit and/or additional testing [which?]).
> 
> The benchmark is here (you need JMH to build and run):
>  http://cr.openjdk.java.net/~shade/8016236/classbench.zip
> 
> Before:
>> Benchmark                                       Mode Thr    Cnt  Sec         Mean   Mean error    Units
>> o.b.ClassBench.generic_getGenericInterfaces     avgt   1      5    1      326.835        1.220  nsec/op
>> o.b.ClassBench.generic_getGenericSuperclass     avgt   1      5    1      308.793        2.828  nsec/op
>> o.b.ClassBench.generic_getTypeParameters        avgt   1      5    1      312.627        1.637  nsec/op
>> o.b.ClassBench.raw_getGenericInterfaces         avgt   1      5    1      216.983        8.902  nsec/op
>> o.b.ClassBench.raw_getGenericSuperclass         avgt   1      5    1       59.933        0.183  nsec/op
>> o.b.ClassBench.raw_getTypeParameters            avgt   1      5    1       65.469        0.284  nsec/op
> 
> Doug's version:
>> Benchmark                                       Mode Thr    Cnt  Sec         Mean   Mean error    Units
>> o.b.ClassBench.generic_getGenericInterfaces     avgt   1      5    1       15.106        0.271  nsec/op
>> o.b.ClassBench.generic_getGenericSuperclass     avgt   1      5    1        5.304        0.024  nsec/op
>> o.b.ClassBench.generic_getTypeParameters        avgt   1      5    1       16.739        0.045  nsec/op
>> o.b.ClassBench.raw_getGenericInterfaces         avgt   1      5    1      213.825        1.346  nsec/op
>> o.b.ClassBench.raw_getGenericSuperclass         avgt   1      5    1       61.651        0.394  nsec/op
>> o.b.ClassBench.raw_getTypeParameters            avgt   1      5    1       64.340        0.522  nsec/op
> 
> After:
>> Benchmark                                       Mode Thr    Cnt  Sec         Mean   Mean error    Units
>> o.b.ClassBench.generic_getGenericInterfaces     avgt   1      5    1       14.985        0.104  nsec/op
>> o.b.ClassBench.generic_getGenericSuperclass     avgt   1      5    1        5.300        0.008  nsec/op
>> o.b.ClassBench.generic_getTypeParameters        avgt   1      5    1       16.874        0.175  nsec/op
>> o.b.ClassBench.raw_getGenericInterfaces         avgt   1      5    1       23.941        0.177  nsec/op
>> o.b.ClassBench.raw_getGenericSuperclass         avgt   1      5    1        8.583        0.044  nsec/op
>> o.b.ClassBench.raw_getTypeParameters            avgt   1      5    1       12.400        0.045  nsec/op
> 
> Thanks,
> Aleksey.