3 ms·

Cooling may be an issue for stacking tons of cpu cores, true. But further increases in cache, RAM, SSD sizes (which may not affect power/cooling as much) will a

• clarry 7y ago
  My understanding is that caches are about as power hungry as the rest of the core, and consume lot of space on the chip, which is why you find large high-TDP desktop & server chips with huge L3s and then mobile chips with rather tiny caches. And huge caches are getting problematic in terms of latency too; if you're doing high performance stuff, you might just have to treat L3 like you used to treat RAM as far as cost of access goes. AIUI we just don't have much to gain on that front unless we can keep actually shrinking the process. RAM and SSD sizes would mainly benefit from becoming cheaper (although even that's not a given if we're stacking layers and effectively multiplying the area -- with possible defects -- by number of layers) but that unfortunately doesn't translate to performance. Both do also run into thermal limits if you try to push performance. Alternatively you can add lanes for more bandwidth, but that doesn't help with latency, and you need more silicon on the CPU to actually handle it. Right now I do not have any performance problem that I could solve by throwing more RAM or SSD at it (but I could just walk into a store and buy either and have enough for years to come; I can't walk into a store and buy a CPU that's fast enough to not be a bottleneck for years to come). Where there are bottlenecks, they are due to CPU execution speed or I/O bandwidth & latency.