[rbanffy]

It was much easier to program though. The Cell had two different ISAs, one for the PPUs and one for the SPUs. The SPUs also didn't have direct access to memory and the PPUs had to manage task assignment and completion, as well as setting up DMA transfers between SPU memory and main memory.

The Phi was closer to the Sun Niagara family - lots and lots of simple, slow, cores, with the note that, in the case of the Phi, the weakling x86's had mighty SIMD abilities while the Niagara had more or less standard SPARC stuff.

Neither will have amazing performance unless you have at least as many threads running as you have cores, and most of the time, at least twice as many. For single-threaded code, they were on the slow side.

Still, I always suggested people use Phis to develop because they'd get a taste of future computers. Nowadays a decent laptop will have half a dozen cores and, unless your mail client has that many threads, it'll not feel as fast as it could be.