@CheckReturnValue
    public static <T> ParallelFlowable<T> from(@NonNull Publisher<? extends T> source) {
        return from(source, Runtime.getRuntime().availableProcessors(), Flowable.bufferSize());
    }
@ CheckReturnValue public static < T > ParallelFlowable < T > from ( @ NonNull Publisher < ? extends T > source ) { return from ( source , Runtime . getRuntime ( ) . availableProcessors ( ) , Flowable . bufferSize ( ) ) ; }
Take a Publisher and prepare to consume it on multiple 'rails' (number of CPUs)
in a round-robin fashion.
@param <T> the value type
@param source the source Publisher
@return the ParallelFlowable instance