A newer garbage collector innovated in the last few years is the G1GC. The G1GC organizes its heap memory differently to the contiguous memory diagram previously seen, used for parallel collectors, such as CMS.
The G1 heap is targeted as a matrix of 2,048 small regions. Each region is between 1 MB and 32 MB, and can be either Eden space, Survivor Space, or (tenured) Old Gen space (Eichwald, 2016). This is demonstrated in the following diagram:
Figure 4.4: A representation of the different sections of the G1GC heap (25 regions shown for brevity)
In the preceding diagram, the E represent the Eden space, the S represent Survivor Space, and ...
