There are two servers with enormous population, due to linkshells recruiting on other sites, causing a snowball effect as more and more people server transfer to those servers to join the group. Odin has a large linkshell for players that speak Japanese, and even if people don't stay in it, it causes spinoff linkshells which keep the server population high. Asura is like that for players that speak English, and with how many countries around the world have such people, the server stays at high population for most of the hours of the day. Reddit was the big influence on Asura, and I don't know which site it was for Odin, but I suspect it was 2ch.