Resources for using std.allocator

[xtreak via Digitalmars-d-learn]

I am newbie to D learning it for sometime using Ali's book. I 
came across std.experimental.allocator and read through 
http://dlang.org/library/std/experimental/allocator/building_blocks.html . Can someone explain me the actual benefits of using this and if so any benchmarks explaining the advantage. Maybe its too advanced for me as a beginner now its just I am curious over the usage and applications with a simple hello world like example explaining what this library will accomplish. I asked it previously at https://www.reddit.com/r/programming/comments/4hti33/dconf_2016_is_streaming_right_now/d2satic/ but still I don't understand the exact applications of the same.