RFR 8062450: Timeout in LowMemoryTest.java

[Jaroslav Bachorik]

On 8.1.2015 03:33, David Holmes wrote:
> On 8/01/2015 3:12 AM, Jaroslav Bachorik wrote:
>> Please, review the following test change
>>
>> Issue : https://bugs.openjdk.java.net/browse/JDK-8062450
>> Webrev: http://cr.openjdk.java.net/~jbachorik/8062450/webrev.00
>>
>> The test times out when "-XX:+ExplicitGCInvokesConcurrent" is specified.
>> The test relies on the MemoryMXBean.gc() invocation returning only after
>> the GC run has been completed. This is not true when
>> "-XX:+ExplicitGCInvokesConcurrent" is set and the test timing is thrown
>> off-balance resulting in deadlock.
>>
>> The proposed solution is to add an appropriate "@requires" JTREG stance
>> to prevent running this test with incompatible settings.
>
> Seems okay - though I'm wondering whether:
>
> @requires vm.opt.ExplicitGCInvokesConcurrent != "true"
>
> has the same affect?

Seems to have the same effect - I tried running the test with 
"-XX:+ExplicitGCInvokesConcurrent", "-XX:-ExplicitGCInvokesConcurrent" 
and without this flag all together and the test was properly ignored 
only when "-XX:+ExplicitGCInvokesConcurrent" is used.

>
> And do you also need to guard against
> ExplicitGCInvokesConcurrentAndUnloadsClasses ?

Didn't see this flag used in testing but it would be wise to guard 
against it as well, thanks. I would throw in DisableExplicitGC too.

-JB-

>
> David
>
>> Thanks,
>>
>> -JB-