6 ms·
The laws of physics are intruding. Clock rate doubling without prohibitive cost, power, and heat have gone. At 3 GHz electrons don't go very far in 1/3rd of a
by sliken 8y ago
The laws of physics are intruding. Clock rate doubling without prohibitive cost, power, and heat have gone. At 3 GHz electrons don't go very far in 1/3rd of a NS. Chips are getting physically bigger (look at the Epyc). Easy increases in IPC are gone. There's an embarrassing number of transistors available, but few uses for them actually increase performance on things consumers care about.
Even GPUs are starting to peter out with lengthening product cycles, smaller improvements, and the increasing tendency to just rename the previous generation with a new name, as if it was actually significantly improved.
So CPUs have peaked, most of the low hanging fruit has already been taken. Most easily shown by pretty much all the popular CPUs from the previous generation maxed out at 95 watts or so (desktop or server), but are at 180 watts in the current generation. This happened years ago for desktops, but is hitting laptops (last year), and smart phones (this year or so).
GPUs are about half way there, improvements are harder. No more annual updates with 2x the performance on most common use cases. Feature improvements are getting more obscure, gaming sites are using 16x zoom to show the improvements. GTX1170 is rumored to be 50% faster than the GTX1070... from 2 years ago.
Specific use ASICs for mining, AI, and similarly narrow use cases are still early in their development. Multiple vendors are showing 2x improvements with each generation, even crazy things like including said chips in consumer devices with tiny power budgets.
So basically a core twice as fast isn't happening, it's not because anyone is lazy. There's tons of room for improvement in specific use cases where today's silicon is crazy inefficient. Things like machine learning, software device radios, vision specific processing, and related are seeing rapid improvements.
- merinowool 8y agoI think it is not happening because it doesn't have to. Current CPUs are more than fine for home user and HEDT market is too small to excuse huge spending for research. I think once electron apps will become more popular home users will get power hungry again and that will kick off another cpu revolution.
- muxr 8y agoIt's not happening because it's hard to do. Extracting instruction level parallelism is difficult(which is how CPUs gain IPC) and then also the cores have to be wider with exponential complexity. ie. At the point you have to sacrifice 50% of CPU's power efficiency for 5% IPC gain, it's no longer worth it.
- B1FF_PSUVM 8y ago(Very good points, small doubt to pick) > Chips are getting physically bigger They are? Over the years, I got the notion that the cheap controller chips were about 30 mm2, the regular desktop CPUs about 100 mm2, and server class powerhouses around 300 mm2. With a quick look, I found mention of Epyc being four 200 mm2 dies packed together: https://www.eetimes.com/author.asp?section_id=36&doc_id=1331764 https://www.eetimes.com/author.asp?section_id=36&doc_id=1331... Wafers have gotten bigger, https://en.wikipedia.org/wiki/Wafer_(electronics) https://en.wikipedia.org/wiki/Wafer_(electronics), but I suppose that manufacturers just want more dies per wafer, not larger dies.
- sliken 8y agoEpyc chip (the package including the 4 ASICS) is pretty huge. It's a decent fraction of a mini-itx motherboard just for the socket. The good news is that while it takes twice the power (170-190 watts or so, 250 in the next generation) it's much easier to dissipate that much with such a large chip. The head density is as low or lower than previous generations. AMD was pretty krafty with this generation. Intel has a huge R&D budget, has it's own fabs, and pushes many different ASICs split into a dizzying array of products. Intel can afford this because they have a MUCH higher volume of parts to amortize the costs over. To compete at many different price/power/performance points AMD uses the exact same ASIC for desktop (1 ASICs with 2 memory channels), workstation (2 ASICs with 4 memory channels), and server (4 ASICS with 8 memory channels). Now AMD can compete across a decent fraction of Intel's produces with a single ASIC and spend more R&D on the second generation without having to re-engineer an entire family of ASICs. Compare any photos of a threadripper or epyc chip, they are easily visible even onstage, it's about as big as the palm of your hand. I believe it's 69.2 mm x 57.9 mm according to a spec I found on the TR4 socket.
- ashleyn 8y agoHeterogenous computing is picking up the slack. More dedicated ASICs for things like vision processing and deep learning. Today's floating-point unit is tomorrow's on-board media processor.