DDIO is a re-architected method of DCA- enabled at the platform level. The differences are substantial, while the intent is the same.
DDIO, when properly optimized with an application can improve latency from comparable previous generation architecture. The key consideration will be the affinitization of the cores so as to avoid going over the QPI bus which is non-optimal for a low latency solution. See the Proc-Int Affinity on Xeon(r) Servers with DDIO Application Note for more details.