RFR: 8150183: gc/g1/plab/TestPLABResize.java - previous PLAB size should be less than current

Michail Chernov michail.chernov at oracle.com
Thu Feb 25 18:06:07 UTC 2016


Hi Jon,



On 25.02.2016 20:42, Jon Masamitsu wrote:
>
> If you're referring to AppPLABResize, my reading of the code is that 
> it does 3 rounds of
> allocations: first with fixed size of total allocations, second with 
> decreasing sizes of allocation,
> third with increasing sizes of allocation.
>
> http://cr.openjdk.java.net/~mchernov/8150183/webrev.00/test/gc/g1/plab/TestPLABResize.java.frames.html 
>
>
>>   123         // Check that desired plab size was changed during 
>> iterations.
>>   124         // It should decrease during first half of iterations
>>   125         // and increase after.
>> 126 long startDesiredPLABSize = plabSizes.get(testCase.getIterations());
>> 127 long endDesiredPLABSize = plabSizes.get(testCase.getIterations() 
>> * 2 - 1);
>
>
> I think a better comment would be (replace line 124 and 125)
>
> // The test case does 3 rounds of allocations.  The second round of N 
> allocations and GC's
> // has a decreasing size of allocations so that iterations N to 2*N -1 
> will be of decreasing size.
> // The third round with iterations 2*N to 3*N -1 has increasing sizes 
> of allocation.
>
> Otherwise, changes look good.
>

Yes, you're right, I referred to AppPLABresize. Thanks a lot, will 
update comments according to your and Dima's recommendations before pushing.

Misha


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