[mattnewport]

Big little cores like on mobile or some Intel processors are really not the same thing. The little cores have the same instruction set and address the same memory as the big cores and are pretty transparent to devs apart from some different performance characteristics.

The SPEs were a different instruction set with a different compiler tool chain running separate binaries. You didn't have access to an OS or much of a standard library, you only had 256K of memory shared between code and data. You had to set up DMA transfers to access data from main memory. There was no concept of memory protection so you could easily stomp over code with a write to a bad pointer (addressing wrapped so any pointer value including 0 was valid to write to). Most systems would have to be more or less completely rewritten to take advantage of them.