This white paper looks at the effect of using the HiperDispatch feature (introduced with z/VM 6.3) with a mixed Linux workload. It also provides results for applying the scalability APAR VM65586.
The improvements in the mixed workload including Websphere and Oracle DB shows that this APAR is not only valuable for z13, but rather for everyone with a larger number of IFLs. And if you are still running an old pre 6.3 z/VM release, now is the time to upgrade!