Looking through the links, and methodology makes me question a lot of things, most of them regarding his choices in how he allocated memory. First and foremost, he was using the glibc malloc, which belongs in a museum, not in a running system. One of rust's big advantages in performance comes from that alone, given all the memory that's being allocated and destroyed. Which leads to the second question of how he did allocate objects. He knew he was going to allocate a number of objects, yet he didn't pre-allocate a large chunk of memory ahead of time to make it so he wouldn't have to call malloc and friends as often. I wouldn't be surprised if spending a bit of time just tuning memory didn't cut significant time from how long execution takes. I really wonder how much time was spent in the system context of all three of those; I'd be willing to bet that the final part of the examination would probably fare much different had he used the same malloc for the C program that rust and go already use.