RFR: JEP 359-Records: hotspot runtime and serviceability code

[Harold Seigel]

Thanks Ioi!

Harold

On 10/22/2019 12:42 AM, Ioi Lam wrote:
> On 10/21/19 11:40 AM, Lois Foltan wrote:
>> On 10/18/2019 2:44 PM, Vicente Romero wrote:
>>> Hi,
>>>
>>> Please review the hotspot runtime and serviceability code for JEP 
>>> 359 (Records).
>>>
>>> Thanks in advance for the feedback,
>>> Vicente
>>>
>>> PS, Thanks to Harold for the development
>>>
>>>
>>> [1] 
>>> http://cr.openjdk.java.net/~vromero/records.review/hotspot_runtime/webrev.00/
>>
>> Harold, Vicente,
>>
>> src/hotspot/share/oops/recordComponent.hpp
>> - line #95 - determination of TBD comment needed before committing.
>
> This code is correct and the TBD can be removed.
>
>     void collect_statistics(KlassSizeStats *sz) const {
>       // TBD is this right?
>       if (_annotations != NULL) {
>         sz->_annotations_bytes += sz->count(_annotations);
>         sz->_ro_bytes += sz->count(_annotations);
>       }
>       if (_type_annotations != NULL) {
>         sz->_annotations_bytes += sz->count(_type_annotations);
>         sz->_ro_bytes += sz->count(_type_annotations);
>       }
>     }
>
> You can test this by running a JVM with something like:
>
> jcmd <pid> Wait GC.class_stats 
> IK_inner_classes,IK_nest_members,IK_record_components
>
>
> Note that this will print out "WARNING: Ran out of C-heap; 
> undercounted 368 total instances in data below". This is JDK-8232758, 
> which you can safely ignore for now.
>
> BTW, all the collect_statistics() functions are pretty complicated and 
> it's unclear whether GC.class_stats is still useful (I implemented it 
> but I don't use it anymore). I have filed JDK-8232759.
>
> Thanks
> - Ioi
>
>