Fix for JDK-8048556 (GCLocker issues): feedback and some testing please?

[Tony Printezis]

Mikael,

Inline.

On 9/1/14, 10:38 AM, Mikael Gerdin wrote:
> Hi Tony,
>
> On 2014-08-28 04:06, Tony Printezis wrote:
>> Hi all,
>>
>> I have a fix for the GCLocker causing unnecessary young GCs issue
>> (JDK-8048556). Here's the webrev:
>>
>> http://cr.openjdk.java.net/~tonyp/8048556/webrev.0/
>>
>> Any chance of a) getting some feedback on whether the fix is reasonable
>> and b) getting it through some testing (I did as much testing as I could
>> but you know how fragile the GCLocker is...)?
>
> I've started some testing on this fix (JPRT, GC test suite).

Thanks!

>>
>> I didn't really want to change the CollectedHeap API. However, I can't
>> work out another way to pass the two GC counts to the VM op without
>> changes to the CollectedHeap. I could have expanded the collect() method
>> to also accept the count arguments. However, I don't think collect()
>> should really be used for the GCLocker GC and I feel that a separate
>> method is appropriate here.
>
> I agree that it's reasonable to have a separate collect_for_gc_locker.

Definitely less confusing in the long term...

>>
>> I also ended up renaming an argument to a c'tor from _cause to cause, as
>> the former should only be used for class members. Hope that's OK.
>
> Yep, that's always bothered me.

I aim to please. :-)

Tony

>>
>> Thanks,
>>
>> Tony
>>

-- 
Tony Printezis | JVM/GC Engineer / VM Team | Twitter

@TonyPrintezis
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