1. A method, with a server system in an out-of-core processing environment, for prefetching data, the method comprising: receiving, from a set of accelerator systems, a set of prefetch requests associated with one or more given datasets residing on the server system; prefetching, for at least one prefetch request in the set of prefetch requests, a set of data from a memory system residing at the server system, wherein the set of data satisfies the at least one prefetch request; and sending the set of data that has been prefetched to at least one accelerator system, in the set of accelerator systems, associated with the at least one prefetch request.