Concurrent Marking in G1
Posted on August 18, 2022
A recent change fundamentally changed how G1 uses mark bitmaps to store liveness information: instead of recording this information using two bitmaps spanning the heap that G1 uses alternatingly, there is now only one bitmap. This not only changes how G1 uses the bitmap in many places in the garbage collector, but also reduces G1 garbage collector native memory consumption by a large amount, to be exact by 1.5% of Java heap size...
More at https://tschatzl.github.io/2022/08/04/concurrent-marking.html