RFR(xxs): 8203032: PrintMetaspaceDcmd fails: 'Non-Class:' missing from stdout/stderr

[Zhengyu Gu]

Looks good to me.

Thanks,

-Zhengyu

On 05/15/2018 08:04 AM, Thomas Stüfe wrote:
> Hi,
> 
> I was able to reproduce the original bug by passing
> -javaoptions:-XX:-UseCompressedOops to the jtreg harness, and I
> verified that my proposed fix actually works. No firther tests needed.
> 
> Now I only need a second (Reviewer) review, since Axel is only Committer.
> 
> ..Thomas
> 
> On Mon, May 14, 2018 at 3:31 PM, Thomas Stüfe <thomas.stuefe at gmail.com> wrote:
>> (webrev: http://cr.openjdk.java.net/~stuefe/webrevs/8203032-PrintMetaspaceDCmd-fails/webrev.00/webrev/)
>>
>> Thanks, Thomas
>>
>> On Mon, May 14, 2018 at 11:52 AM, Thomas Stüfe <thomas.stuefe at gmail.com> wrote:
>>> Hi all,
>>>
>>> may I please have reviews for this small fix:
>>>
>>> Bug: https://bugs.openjdk.java.net/browse/JDK-8203032
>>>
>>> Fix:
>>>
>>> diff -r 2f79462aab9b
>>> test/hotspot/jtreg/runtime/Metaspace/PrintMetaspaceDcmd.java
>>> --- a/test/hotspot/jtreg/runtime/Metaspace/PrintMetaspaceDcmd.java
>>>   Mon May 07 09:11:21 2018 +0200
>>> +++ b/test/hotspot/jtreg/runtime/Metaspace/PrintMetaspaceDcmd.java
>>>   Mon May 14 11:46:23 2018 +0200
>>> @@ -33,8 +33,8 @@
>>>    * @library /test/lib
>>>    * @modules java.base/jdk.internal.misc
>>>    *          java.management
>>> - * @run main/othervm -XX:MaxMetaspaceSize=201M -XX:+VerifyMetaspace
>>> -XX:+UseCompressedClassPointers PrintMetaspaceDcmd
>>> with-compressed-class-space
>>> - * @run main/othervm -XX:MaxMetaspaceSize=201M -XX:+VerifyMetaspace
>>> -XX:-UseCompressedClassPointers PrintMetaspaceDcmd
>>> without-compressed-class-space
>>> + * @run main/othervm -XX:MaxMetaspaceSize=201M -Xmx100M
>>> -XX:+UseCompressedOops -XX:+UseCompressedClassPointers
>>> PrintMetaspaceDcmd with-compressed-class-space
>>> + * @run main/othervm -XX:MaxMetaspaceSize=201M -Xmx100M
>>> -XX:-UseCompressedOops -XX:-UseCompressedClassPointers
>>> PrintMetaspaceDcmd without-compressed-class-space
>>>    */
>>>
>>>
>>> There had been two issues:
>>>
>>> 1) I let the test run with -XX:+VerifyMetaspace, but that one is a
>>> debug only option, so the test fails in release build. Well, that was
>>> just stupid :)
>>>
>>> My fix is to just remove the option, since I do not know how to
>>> specify an option for debug VMs only.
>>>
>>> 2) The test requires the VM to be started with
>>> +UseCompressedClassPointers, and assumed +UseCompressedOops would be
>>> always set, because it is default. However, the test is started with
>>> CompressedOops explicitly turned off. I do not understand why but my
>>> assumtion is that it has to do with -XX:MaxRAMPercentage=8 and running
>>> on a big machine, where 8% of the available RAM would bring the VM
>>> above the max. 32G heapsize needed to have compressed oops.
>>>
>>> My fix is to first, specify -XX:+UseCompressedOops explicitly, and
>>> second to limit the max heap size to -Xmx100M. I hope this will
>>> overrule the -XX:MaxRAMPercentage=8 handed down from above? But since
>>> I do not know exactly via which way this option came down, I cannot
>>> reproduce and test. So, I would be obliged if someone could test if
>>> this fix fixes the issues on Oracles tests.
>>>
>>>
>>> Thanks, Thomas