RFR 8078555(M): GC: implement ranges (optionally constraints) for those flags that have them missing

Derek White derek.white at oracle.com
Wed Aug 26 17:59:33 UTC 2015

Hi Sangheon,

I haven't reviewed the actual ranges and constraints yet, but one thing 
you might want to consider:

For the test cases, you may want synchronize the GC specified to 
ProcessBuilder with the "@requires gc=" tags. This prevents the test 
harness from running G1 tests when the test harness is trying to run CMS 
test, etc, and also avoids potential confusing test failures.

  @requires vm.gc=="G1" | vm.gc=="null"
  (or specify Parallel GC as needed).

This is for:
TestG1ConcMarkStepDurationMillis.java (G1)
TestObjectTenuringFlags.java (Parallel)
TestInitialTenuringThreshold.java (Parallel)
TestG1HeapRegionSize.java (G1)

  - Derek

On 8/24/15 5:33 PM, sangheon.kim wrote:
> Hi Kim,
> On 08/24/2015 02:16 PM, Kim Barrett wrote:
>> On Aug 24, 2015, at 3:06 PM, sangheon.kim <sangheon.kim at oracle.com> 
>> wrote:
>>> Hi Kim,
>>> Here's webrev.03 which includes your comment for MarkStackSize 
>>> constraint function.
>>> http://cr.openjdk.java.net/~sangheki/8078555/webrev.03
>>> http://cr.openjdk.java.net/~sangheki/8078555/webrev.03_to_02/
>>> And all your comments will be managed by 
>>> https://bugs.openjdk.java.net/browse/JDK-8134348 .
>> If the value of MarkStackSizeMax were changed later, there's nothing
>> to verify MarkStackSize is still smaller.  [This is related to my
>> earlier comment about constraints between options being tested twice
>> and failures reported twice.]  Do we care in this case?
> If your concern is something like
> -XX:MarkStackSize=128 -XX:MarkStackSizeMax=100.
> Yes, in this case the order is important as ranges and constraint 
> functions are verified by its order.
> MarkStackSizeMax will be verified first(its range) and MarkStackSize 
> will be compared with verified MarkStackSizeMax.
> And as I said your original concern is current limitation.
> If we set CMSOldPLABMin and CMSOldPLABMax together with invalid values 
> (e.g. CMSOldPLABMin=100, CMSOldPLABMax=50),
> they will print out 2 failure messages.
> Thanks,
> Sangheon
>> Other than that, looks good.

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