Request for review: 8004132 SerialGC ValidateMarkSweep code broken

Tao Mao tao.mao at oracle.com
Mon Dec 17 13:02:15 PST 2012


Thank you, John. A new webrev is uploaded as you advised.

http://cr.openjdk.java.net/~tamao/8004132/webrev.01/

I would like to have one more review if possible.

Thanks.
Tao

On 12/13/2012 4:05 PM, John Cuthbertson wrote:
> Hi Tao,
>
> This looks good to me. One comment - the functionality of 
> RecordMarkSweepCompaction depends upon ValidateMarkSweep you might 
> want to remove this flag as well.
>
> JohnC
>
> On 12/04/12 15:47, Tao Mao wrote:
>> 8004132 : SerialGC: ValidateMarkSweep broken when running GCOld
>> http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=8004132
>>
>> http://cr.openjdk.java.net/~tamao/8004132/webrev.00/
>>
>> Passed JPRT; I checked ValidateMarkSweep can't be triggered now with 
>> the fix.
>>
>> Background:
>>
>> While verifying the functionality of the ValidateMarkSweep code with 
>> the Serial collector (prior to adding code to enable this feature in 
>> G1) Tao and myself saw various crashes and failures when running GC Old.
>>
>> Script to run GCOld:
>> #JHOME=/export/jdk8/solaris-x64
>> #JHOME=/java/re/jdk/6/promoted/latest/binaries/solaris-i586/fastdebug
>> JHOME=/export/bugs/8001047/jdk7/solaris-x64
>>
>> $JHOME/bin/java -server -Xms1g -Xmx1g \
>>         -XX:+UseSerialGC \
>>         -XX:+ValidateMarkSweep \
>>         -XX:+PrintGCDetails -XX:+PrintGCTimeStamps 
>> -XX:+ShowMessageBoxOnError \
>>                 GCOld 9000 20 5 30 500000
>>
>> Note the ValidateMarkSweep functionality is only available in 
>> non-product builds.
>>
>> This seems to have been broken for a long while - we even saw the 
>> crash with jdk6. Thus we suggest to remove the ValidateMarkSweep code.
>>
>


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