RFR: 7169803: Usage of pretenured value is not correct

David Lindholm david.lindholm at oracle.com
Wed Jun 10 08:30:59 UTC 2015


Jon,

Thanks for taking a look at this. No, I don't think this will lead to 
double counting. This calculation is already there, it is just buggy. 
Before this patch the code added the total amount of promoted memory 
this collection with the average size of the pretenured objects, and 
used this as a sample. Now the code adds the total amount of promoted 
memory with the total size of the pretenured objects since last 
collection, and uses this as a sample instead.


Thanks,
David

On 2015-06-09 21:37, Jon Masamitsu wrote:
> David,
>
> http://cr.openjdk.java.net/~david/JDK-7169803/webrev.00/src/share/vm/gc/parallel/psAdaptiveSizePolicy.cpp.frames.html 
>
>
> 1308   avg_promoted()->sample(promoted + 
> total_pretenured_since_last_promotion());
>
>
> Is including both "promoted" and 
> "total_pretenured_since_last_promotion()"
> double counting?
>
> Jon
>
> On 06/09/2015 02:06 AM, David Lindholm wrote:
>> Hi,
>>
>> Please review this patch that corrects the usage of the pretenured 
>> value. There were 2 issues: words and bytes were mixed up and the 
>> addition was done with the wrong value. See bug for details.
>>
>> Webrev: http://cr.openjdk.java.net/~david/JDK-7169803/webrev.00/
>> Bug: https://bugs.openjdk.java.net/browse/JDK-7169803
>>
>>
>> Testing: Passed JPRT
>>
>>
>> Thanks,
>> David
>



More information about the hotspot-gc-dev mailing list