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Well, intel seems to sorta be proving a point I had a long time about arm's big little setup. Which is that its only needed because their big cores wern't suffi

Well, intel seems to sorta be proving a point I had a long time about arm's big little setup. Which is that its only needed because their big cores wern't sufficiently advanced to be able to scale their power utilization efficiently. If you look at the intel power/perf curves, it the "Efficient" cores are anything but. Lots of people have noticed this, and pointed out its probably not "power Efficient" but rather "die space efficient under constrained power" because they have fallen behind in the density race, and their big cores are quite large. But i'm not even so sure about that, avx-512 is probably part of the size problem with the cores. We shall see, your probably right that hetrogenious might be here to stay, but I suspect a better use of the space long term is even more capable GPU cores offloading the work that might be done on the little cores in the machine. AKA, you get a number of huge/fast/hot cores for all the general purpose "CPU" workloads, and then offload everything that is trivially parallelized to a GPU that is more closely bound to the cores and shares cache/interconnect.

paulmd 4y ago
it's funny because this is sort of addressing a point I made elsewhere in the comments. https://news.ycombinator.com/item?id=33778016 https://news.ycombinator.com/item?id=33778016 Like, serious/honest question, how do you see Gracemont as space-efficient here? It's half the size of a full Zen3 core yet probably at-best produces the same perf-per-area, and uses 1.5x the transistors of Blizzard for similar performance (almost 3x the size, bearing in mind 5nm vs 7nm). that's not really super small, it's just that Intel's P-cores are truly massive, like wow that is a big core even before the cache comes in. For years I thought it would be cool to see an all-out "what if we forget area and just build a really fast wide core" and that's what Intel did. And actually, for as much as people say Apple is using a huge "spare no expenses" core, it's not really all that big even considering the area - you get around 1.5-1.6x area scaling between 5nm and 7nm as demonstrated by both Apple cores and NVIDIA GPUs, and probably close to AMD's numbers as well. So just looking at it at a transistor level, Apple is using 2.55 x 1.6 = 4.08mm2 equivalent of silicon and Intel is using 5.55mm2, so Apple is only using 75% of the transistors of Intel's golden cove p-core... But in the e-core space, it's become a meme that Gracemont is "size efficient rather than power efficient" and I'm just not sure what that means in practical terms. Usually high-density libraries are low-power, so those two things normally go together... and it's certainly not like they're achieving unprecedented perf-per-area, they're probably no better than Zen3 in that respect. Where is the space efficiency in this situation if it's not libraries or topline perf-per-area?

paulmd 4y ago

it's funny because this is sort of addressing a point I made elsewhere in the comments. https://news.ycombinator.com/item?id=33778016 https://news.ycombinator.com/item?id=33778016 Like, serious/honest question, how do you see Gracemont as space-efficient here? It's half the size of a full Zen3 core yet probably at-best produces the same perf-per-area, and uses 1.5x the transistors of Blizzard for similar performance (almost 3x the size, bearing in mind 5nm vs 7nm). that's not really super small, it's just that Intel's P-cores are truly massive, like wow that is a big core even before the cache comes in. For years I thought it would be cool to see an all-out "what if we forget area and just build a really fast wide core" and that's what Intel did. And actually, for as much as people say Apple is using a huge "spare no expenses" core, it's not really all that big even considering the area - you get around 1.5-1.6x area scaling between 5nm and 7nm as demonstrated by both Apple cores and NVIDIA GPUs, and probably close to AMD's numbers as well. So just looking at it at a transistor level, Apple is using 2.55 x 1.6 = 4.08mm2 equivalent of silicon and Intel is using 5.55mm2, so Apple is only using 75% of the transistors of Intel's golden cove p-core... But in the e-core space, it's become a meme that Gracemont is "size efficient rather than power efficient" and I'm just not sure what that means in practical terms. Usually high-density libraries are low-power, so those two things normally go together... and it's certainly not like they're achieving unprecedented perf-per-area, they're probably no better than Zen3 in that respect. Where is the space efficiency in this situation if it's not libraries or topline perf-per-area?