RFR(S): 8011343: Add new flag for verifying the heap during startup

[John Cuthbertson]

Hi Bengt,

Thanks for looking the changes over.

JohnC

On 4/4/2013 6:47 AM, Bengt Rutisson wrote:
>
> Hi John,
>
> Thanks for fixing this!
>
> Looks good!
> Bengt
>
> On 4/3/13 1:32 AM, John Cuthbertson wrote:
>> Hi Everyone,
>>
>> Can I have a couple of reviews for this change please? The webrev can 
>> be found at: http://cr.openjdk.java.net/~johnc/8011343/webrev.0/
>>
>> Summary:
>> During the code review for 8010463 it was suggested that the 
>> verification that is performed during VM startup should be done under 
>> control of a new flag rather than piggy-backing off the 
>> VerifyBeforeGC flag. In response to another comment I suggested that 
>> the verification should be done using a VM Operation so as to 
>> maximize the verification (certain parts of the G1 heap are skipped 
>> if the verification is not performed at a safepoint).
>>
>> These changes address these comments.
>>
>> Testing:
>> GC test suite with the new flag
>> jprt with the new flag (this configuration saw some failures that are 
>> caused by the issue described in 8010943)
>> jtreg with the changed regression test
>>
>> Note: I think the warning(s) emitted from arguments.cpp when 
>> FLSVerifyAllHeapReferences is enabled can be removed (now that 
>> verification is performed at a safepoint) but I am loathe to do so. 
>> Testing this configuration resulted in some assertion failures (even 
>> with a new workspace) that I'll be submitting another CR for.
>>
>> Thanks,
>>
>> JohnC
>>
>>
>