[12] RFR (T): 8146090: java/lang/ref/ReachabilityFenceTest.java fails with -XX:+DeoptimizeALot

[David Holmes]

Hi Vladimir,

On 4/12/2018 3:10 pm, Vladimir Ivanov wrote:
> 
>> I just added a query to the bug report. I can't tell what other flags 
>> get tested in same run that uses DeoptimizeALot. Is it better to 
>> exclude the test from all such runs, or to force DeoptimizeALot off in 
>> the @run lines?
> 
> The flag is used in hs-comp testing (tier7-8) and it turns on 
> heavyweight stress mode. The actual flag combinations being tested are:
> 
>    -ea -esa -XX:CompileThreshold=100 -server -XX:[+-]TieredCompilation 
> [-Xcomp] -XX:+DeoptimizeALot
> 
> I'm in favor of excluding the test, since I don't see much value in 
> running the test with the flag explicitly disabled: it duplicates 
> testing in other configurations.

Which other tier config would this duplicate? As long as we are stress 
testing the reachability fence then I'm okay with this, but I want to be 
sure we are stress testing it. Ensuring reachability fences are kept in 
place and maintain object liveness is exactly what we need to check 
under heavy compilation etc.

Thanks,
David

>> PS. Please update the copyright line to add 2018.
> Sure, will do.
> 
> Best regards,
> Vladimir Ivanov