RFR (XS) 8205702: assert(UseCompressedClassPointers) failed in universe.hpp

[Calvin Cheung]

On 6/26/18, 4:09 PM, coleen.phillimore at oracle.com wrote:
>
> Hi Calvin, thank you for reporting the bug and the code review and 
> test code.
>
> On 6/26/18 5:42 PM, Calvin Cheung wrote:
>> Hi Coleen,
>>
>> The code changes look good.
>>
>> Since there's a new error message, I'd suggest adding a test to 
>> runtime/SharedArchiveFile/SharedArchiveFile.java as follows:
>>
>> diff --git 
>> a/test/hotspot/jtreg/runtime/SharedArchiveFile/SharedArchiveFile.java 
>> b/test/hotspot/jtreg/runtime/SharedArchiveFile/SharedArchiveFile.java
>> --- 
>> a/test/hotspot/jtreg/runtime/SharedArchiveFile/SharedArchiveFile.java
>> +++ 
>> b/test/hotspot/jtreg/runtime/SharedArchiveFile/SharedArchiveFile.java
>> @@ -52,5 +52,13 @@
>>                                "-Xshare:on", "-version");
>>          out = CDSTestUtils.executeAndLog(pb, "SharedArchiveFile");
>>          CDSTestUtils.checkExec(out);
>> +
>> +        // CDS dumping doesn't work with ZGC
>> +        ProcessBuilder pb = ProcessTools.createJavaProcessBuilder(true,
>> + "-XX:SharedArchiveFile=./SharedArchiveFile.jsa",
>> +                                "-XX:+UseZGC",
>> +                                "-Xshare:dump");
>> +        out = CDSTestUtils.executeAndLog(pb, "SharedArchiveFile");
>> +        CDSTestUtils.checkExecExpectError(out, 1, "DumpSharedSpaces 
>> (-Xshare:dump) is not supported with ZGC.");
>>      }
>>  }
>>
>> (I haven't tested the above)
>
> It needed an -XX:+UnlockExperimentalVMOptions as well, and not reclare 
> pb.
>
> open webrev at http://cr.openjdk.java.net/~coleenp/8205702.02/webrev
Looks good.
>
>>
>> Also, I think the new error message should be included in the release 
>> notes.
>>
>
> I added the test case and it passes.  I don't think having a release 
> note for something that nobody would ever do for an experimental 
> option is worth having.   But I can look into the ZGC release notes 
> and see if there's something that says CDS is not supported.
Perhaps you can add something to 
https://bugs.openjdk.java.net/browse/JDK-8205334?

thanks,
Calvin
>
> Thanks,
> Coleen
>> thanks,
>> Calvin
>>
>> On 6/26/18, 2:13 PM, coleen.phillimore at oracle.com wrote:
>>> Summary: Disable CDS with ZGC
>>>
>>> Tested with:
>>> java -XX:+UnlockExperimentalVMOptions -XX:+UseZGC -Xshare:dump
>>> java -XX:+UnlockExperimentalOptions -XX:+UseZGC -Xshare:on -version
>>>
>>> open webrev at http://cr.openjdk.java.net/~coleenp/8205702.01/webrev
>>> bug link https://bugs.openjdk.java.net/browse/JDK-8205702
>>>
>>> Thanks,
>>> Coleen
>