Cache issues add another layer here, if it's not the whole issue. Device tree patches for the K3 have 2 clusters of 4 cores with shared 4MB L2 cache per cluster

Cache issues add another layer here, if it's not the whole issue. Device tree patches for the K3 have 2 clusters of 4 cores with shared 4MB L2 cache per cluster. Core 2 Duo P8400 has 3MB L2 shared between 2 cores, and Sandybridge-Haswell have per core L2 and shared L3.