Cache and memory in the many-core era
 

One of the greatest challenges facing the designers of many-core processors is resource contention. The chart below visually lays out the problem of resource contention, but for most of us the idea is intuitively easy to grasp: more cores and more simultaneous threads means more contention for shared resources, specifically cache space and memory bandwidth.

http://arstechnica.com/articles/paed...-many-core.ars