Daniel Lemire's blog

, 2 min read

Science and Technology links (December 4th 2021)

  1. It used to be that all the exciting new processors came from Intel and AMD, and they were meant for your PC. The mobile revolution changed that: it lead to the production of fantastic processors that used little energy. We are now moving back into laptops and servers. The leading supplier of servers is probably Amazon: if you want to run servers for your business, your first choice is often Amazon and its cloud computing infrastructure. And Amazon now makes their own processors. Initially, they made low-cost chips that were secondary to Intel and AMD powerful processors. Amazon released its latest processor, Graviton 3. It is a much wider and deeper chip:

The N1 core used in the Graviton2 chip had an instruction fetch unit that was 4 to 8 instructions wide and 4 wide instruction decoder that fed into an 8 wide issue unit that included two SIMD units, two load/store units, three arithmetic units, and a branch unit. With the Perseus N2 core used in the Graviton3, there is an 8 wide fetch unit that feeds into a 5 wide to 8 wide decode unit, which in turn feeds into a 15 wide issue unit, which is basically twice as wide as that on the N1 core used in the Graviton2. The vector engines have twice as much width (and support for BFloat16 mixed precision operations) and the load/store. arithmetic, and branch units are all doubled up, too.

It feels like we are witnessing a revolution in processors. Not only are corporations like Apple and Amazon making their own chips… they appear to match Intel in raw power.

  1. Despite generous Danish social policies, family influence on important child outcomes in Denmark is about as strong as it is in the United States.
  2. Clearing senescent (old) cells appears to also clear out diabetes (in mice).
  3. South Korea is building a self-sustaining floating city.
  4. A supplement based on alpha-ketoglutarate appears to have strong rejuvenation effects (in human beings).
  5. Metformin is a commonly used drug which is believed to have some anti-aging properties. However some research suggested that metformin could blunt the beneficial effects of exercise. A recent clinical trial indicates that these fears are unwarranted.
  6. Biological aging (senescence) could have evolved when animals first colonized the land, from the sea.
  7. Your favorite colour reveals nothing about your personality.