The road to Zettalinux [LWN.net]

The road to Zettalinux

Posted Sep 19, 2022 17:34 UTC (Mon) by linuxrocks123 (subscriber, #34648)
In reply to: The road to Zettalinux by Cyberax
Parent article: The road to Zettalinux

https://en.wikipedia.org/wiki/Transistor_count

Go back to 2010. Most dense released processor had a transistor density of 4,875,000 transistors per square millimeter. According to Moore's Law, processors in 2022 should have pow(2,6)=64 times as many transistors per square millimeter today. That would be 312,000,000 transistors per square millimeter. Reality? 139,300,000 per square millimeter.

It's dead, Jim.

The road to Zettalinux

Posted Sep 19, 2022 19:51 UTC (Mon) by Wol (subscriber, #4433) [Link]

So we've missed it by about ONE cycle in TEN years.

If we've missed it, it's "close, have a cigar".

Cheers,
Wol

The road to Zettalinux

Posted Sep 20, 2022 9:59 UTC (Tue) by paulj (subscriber, #341) [Link] (2 responses)

Moore's "law" was about # transistors on a device though, not density per se. If a company can get more transistors on a device with improved processes that deliver higher yield, and so can produce a device with more transistors by virtue of being able to produce a larger device for essentially the same cost, then that contributes to Moore's "law", regardless of density.

The road to Zettalinux

Posted Sep 20, 2022 10:02 UTC (Tue) by paulj (subscriber, #341) [Link]

Subject for discussion: Does 'chiplet' technology count towards Moore's "law"? Should a set of chiplets, bound together on a single silicon substrate signalling and power/clock, be considered one 'device' for the purposes of Moore's law?

Cause that technology has enabled manufacturers to produce GPUs and CPUs with far greater numbers of transistors than would have been (economically) possible before...

The road to Zettalinux

Posted Sep 20, 2022 11:05 UTC (Tue) by farnz (subscriber, #17727) [Link]

It wasn't even about # transistors on a device - it was about # transistors you could affordably put on a single device. In its original form, Moore speculated that the number of transistors you could get on one device at the cheapest cost-per-transistor would double every 18 months - you can get this by doubling the number of transistors you put on a device while holding the price fixed, or you can halve the cost per transistor and still meet the original formulation - indeed, if you look at the original article by Dr Moore, the graph on page 2 suggests that even when he came up with the rule, it was already the case that you got both reduced cost-per-transistor and increased density working together to make the rule true.

People forget that Moore's Law is purely about the economics of producing more complex devices - for as long as it holds, it's a good engineering tradeoff to assume that, if you can only afford $50 per IC manufactured, you'll be able to buy the equivalent of today's $100 one in 18 months (or whatever the current Moore's Law timeframe is) and thus can plan for being able to afford that complexity, rather than trying to make your design fit within the $50 choice.

But with Dennard scaling coming to an end (because leakage currents can no longer be neglected), this doesn't necessarily translate into improved performance, or improved energy consumption - just into reduced price for devices of a given complexity. This has been most evident in games console pricing - at launch, they're using devices that are slightly too expensive for the product, preventing the console maker from profiting on the hardware, but within 5 years, you're getting cost-reduced versions where the console maker is making a profit on the reduced price version.