Request for review: 8004132 SerialGC ValidateMarkSweep code broken

Tao Mao tao.mao at
Tue Dec 4 23:47:53 UTC 2012

8004132 : SerialGC: ValidateMarkSweep broken when running GCOld

Passed JPRT; I checked ValidateMarkSweep can't be triggered now with the 


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/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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