[9] RFR (S): 8148940: java/lang/ref/FinalizeOverride.java can time out due to frequent safepointing

Zoltán Majó zoltan.majo at oracle.com
Thu Feb 25 16:27:35 UTC 2016


please review the patch for 8148940:


Problem: Since Indify String Concatenation (JDK-8148483) was pushed, the 
execution time of the FinalizeOverride.java test increased by 2-89X.

The increase can be measured both with -Xmixed and -Xcomp and it results 
from a combination of two main factors:
(1) The test spends an increased amount of time in the VM (e.g., because 
an ISC-enabled build can trigger up to 2X more compilations than a 
non-ISC-enabled build);
(2) The test triggers safepointing frequently.

Here are more details on these factors and the exact cause of the failure:

Possible solutions: Update the test to give more chance to the VM to 
progress. I see two ways of doing that:
Solution #1: Reduce the freqency of triggering GCs

Solution #2: Remove string operations from finalizers.

Solution #2 is faster, but it makes more difficult to monitor the 
progress of the test than in the case of Solution #1.

Here are the execution times for both solutions on two platforms:

Testing: Executed the updated test on the both platforms used for 

Thank you!

Best regards,



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