This IBM Support web site is a great starting point for Db2 for i. It provides an introduction to Db2 for i and has many links to additional information.
IBM’s Mike Cain explains the importance of the introduction of parallelism for IBM i on Power.
This document describes how SMP affects batch run times.
This technical paper by Kent Milligan explains the Db2 Symmetric MultiProcessing (Db2 SMP) licensed feature.
Mike Cain’s educational paper on Db2 for IBM i Symmetric Multiprocessing Database Parallelism.