JEP 189: Shenandoah: An Ultra-Low-Pause-Time Garbage Collector

Tony Printezis tprintezis at
Wed Feb 5 18:00:50 UTC 2014


On 2/4/14, 6:39 PM, Roman Kennke wrote:
>> Will Shenandoah try to reuse the existing write barrier logic in
>> HotSpot and extend it to catch all field writes as opposed to just
>> reference field writes, or will it use some other form of write
>> barrier?
> It uses the G1 barrier for SATB and extends it for the preemptive
> copying.

But you didn't answer Krystal's question, though. :-) Given that the JEP 
says "All writes to objects in targeted regions must first copy the 
object and then write to the object in its new location", don't you have 
to extend the write barrier for scalar writes too?



Tony Printezis | JVM/GC Engineer / VM Team | Twitter

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