RFR: JDK-8072913: [REDO] GCCause should distinguish jcmd GC.run from System.gc()

[Yasumasa Suenaga]

Hi all,

> So I think we can remove _jvmti_force_gc from is_user_requested_gc() and add _dcmd_gc_run
> to it.

I've uploaded new webrev, and I've applied it to new patch.
Could you review it?

http://cr.openjdk.java.net/~ysuenaga/JDK-8072913/webrev.01/

I also updated jtreg testcase.
It works fine in my environment.


Thanks,

Yasumasa


On 2015/02/14 22:10, Yasumasa Suenaga wrote:
> Hi Mikael,
>
>> I'd prefer if you could add a GCCause::is_system_gc_equivalent() which returns true for some set of GCCause enum values, such as _java_lang_system_gc and _dcmd_gc_run
>
> Can I add _dcmd_gc_run to GCCause::is_user_requested_gc() ?
> This function is used with GCCause::is_serviceability_requested_gc() .
> CMSCollector::is_external_interruption() and AdaptiveSizePolicy::check_gc_overhead_limit()
>
> is_user_requested_gc() and is_serviceability_requested_gc() checkes _jvmti_force_gc
> is selected.
> So I think we can remove _jvmti_force_gc from is_user_requested_gc() and add _dcmd_gc_run
> to it.
>
>> A "grep" for _java_lang_system_gc should yield more places where updates may be necessary.
>
> We can use GCCause::is_user_requested_gc() if the proposal in above is accepted.
>
>
> Thanks
>
> Yasumasa
>
>
>
> On 2015/02/13 21:33, Mikael Gerdin wrote:
>> Hi Yasumasa,
>>
>> On 2015-02-11 15:02, Yasumasa Suenaga wrote:
>>> Hi all,
>>>
>>> I've committed JDK-8068589 to add new GCCause - Diagnostic Command.
>>> However, it has been backouted because test is failed [1] and it is not considered
>>> about concurrent GC: -XX:+ExplicitGCInvokesConcurrent [2].
>>>
>>> I've created patch for this enhancement.
>>> Could you review it?
>>>
>>> http://cr.openjdk.java.net/~ysuenaga/JDK-8072913/webrev.00/
>>
>> I'd prefer if you could add a GCCause::is_system_gc_equivalent() which returns true for some set of GCCause enum values, such as _java_lang_system_gc and _dcmd_gc_run
>>
>> Given that the documentation of the GC.run command is:
>> "GC.run
>> Call java.lang.System.gc().
>>
>> Impact: Medium: Depends on Java heap size and content.
>>
>> Syntax: GC.run"
>>
>> I interpret the documentation that the GC is supposed to be (for all intents and purposes) equivalent to the application invoking System.gc().
>>
>> This would also require updates to other places where we refer to the _java_lang_system_gc GCCause, such as UseAdaptiveSizePolicyWithSystemGC
>>
>> A "grep" for _java_lang_system_gc should yield more places where updates may be necessary.
>>
>> /Mikael
>>
>>>
>>>
>>> I'm jdk9 committer, but I'm not employee at Oracle.
>>> So I need a Sponsor.
>>>
>>>
>>> Thanks,
>>>
>>> Yasumasa
>>>
>>>
>>> [1] http://mail.openjdk.java.net/pipermail/hotspot-gc-dev/2015-February/011957.html
>>> [2] http://mail.openjdk.java.net/pipermail/hotspot-gc-dev/2015-February/011962.html
>>>