Google Chrome (v58 used) will request all host entries for an address (A, AAAA, CNAME) and put them into an array (address_list). Chrome will then attempt to open a socket on each IP address in order from first to last, chrome will not attempt the fastest or closest IP, it assumes the first IP (given by your upstream dns resolvers) is the best IP. In my tests bind and windows dns servers give a different order of IPs per lookup, giving what seems like 50/50 split in bandwidth to each IP. This functionality is exposed in chrome://net-internals/#events&q=type:SOCKET%20is:active