The write speed is dependent on a lot of factors, but yes multiple alphas should help as long as they are not replicas (e.g. set --replicas 1 in your startup command for Zero). In that case writes as divided between alphas, not copied to all alphas. Other important factors are the cpu/mem/disk speed available to the alphas, and how many different predicates are in your insert. Dgraph parallelises by predicate (i.e. 1 cpu per predicate), so if you only have say 4 predicates you will be limited to roughly 4 cores. It would be good to know more about your schema, the machine(s) you are running on, and what is the current cpu usage of dgraph as you load it. It is definitely capabable of more than 50,000 rdfs per second.