Could ObjectSizeCalculator.java supported in other JVMs besides HotSpot-JVM?

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Twitter common libraries for python and the JVM (deprecated)

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Could ObjectSizeCalculator.java supported in other JVMs besides HotSpot-JVM? #484

Open leesf opened 4 years ago

leesf commented 4 years ago

Now ObjectSizeCalculator.java could not work in other JVMs, such as IBM JVM, see here, are there any solutions or sugguestions to implement a new one in other JVMs? Thanks

DavisBroda commented 4 years ago

For the IBM JVM specifically, watch out for packed objects, which remove object headers entirely for some objects. Likely complicates the memory model a bit.

https://www.ibm.com/support/knowledgecenter/SSYKE2_7.1.0/com.ibm.java.lnx.71.doc/user/packed_developing.html

DanHeidinga commented 4 years ago

PackedObject support was a tech preview feature that has been removed from the JVM. No need to worry about it as it's never been supported.

vinothchandar commented 4 years ago

Wondering if its easy to extend support for IBM JVM