Computer Organization and Architecture - 11e
by William Stallings
Another organizational design decision in a multicore system is whether the individual cores will implement simultaneous multithreading (SMT). For example, the Intel Core Duo uses pure superscalar cores, whereas the Intel Core i7 uses SMT cores. SMT has the effect of scaling up the number of hardware-level threads that the multicore system supports. Thus, a multicore system with four cores and SMT that supports four simultaneous threads in each core appears the same to the application level as a multicore system with 16 cores. As software is developed to more fully exploit parallel resources, an SMT approach appears to be more attractive than a purely superscalar approach.🏁