[dooferlad]

The rest of the SoC plays a huge part, just like the architecture of a PC does. My personal mantra when thinking of how to get the most out of a CPU is "feed the beast" since idle time is the killer. In the most simplistic terms your L1 caches need to be big enough to hold the program you are running and the data it is using. You can hint to the CPU about what data you will need and get it to preload and branch prediction does a similar job for fetching instructions and avoiding branch misses.

I for one like to see big caches in SoCs, but the cost of putting it there needs to be balanced against the performance requirements of the product (no point having a bigger chip than you need). There is also the numbers game of 64 bit / number of cores / RAM etc which are easy to parse but difficult to understand. An irrelevant number of consumers care about IPC and time taken to wake a core or switch a workload between cores, so great innovations like big little are used as marketing numbers rather than to tune a SoC to its best performance. I would like to see 1 big, 2 little cores and more cache myself.

So what do Apple have? Lots of cores? No. If you build an 8 core SoC and can't keep those cores running then you have listened to marketing.