On Tue, 19 Aug 2025 15:00:15 GMT, Albert Mingkun Yang <ay...@openjdk.org> wrote:
>> The motivation for `total()` is that this is probably what most users want,
>> but in case anyone want a sub-component I also expose each one of them. It
>> also serves as documentation as what we currently consider to be "total", so
>> I would prefer keeping it.
>>
>> If you look at e.g. `WeakProcessor::CountingClosure` the following is
>> defined
>>
>> size_t dead() const { return _old_dead + _new_dead; }
>> size_t new_dead() const { return _new_dead; }
>> size_t total() const { return dead() + _live; }
>>
>>
>> so having such convenience method in hotspot is not unprecedented and I
>> would prefer keeping it.
>>
>> `statistics()` is a less important convenience method that can be removed.
>
> I think the smallest API would be `statisics()`, which returns all
> sub-components, and consumers of this API can calculate other derived
> metrics. YMMV.
I would remove `CPUTimeUsage::GC::statistics()` as I would prefer having
coherent types between classes in the namespace and since using structs over of
classes defeats some of the utility of putting everything into a namespace.
For instance, it makes little sense to define a struct for `Runtime` which only
include one component currently and it would be less than ideal to return
`jlong` for some classes and custom structs for others if we only have to pick
one of these approaches.
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PR Review Comment: https://git.openjdk.org/jdk/pull/26621#discussion_r2285707652
