4 ms·

Is this why there is more attention on PIM - processing in memory? You don’t burn active power?

petra 2y ago
It's mainly as a way to overcome the bandwidth limits between memory and CPU. It will increase the heat density of the memory, but there's room to play there. Plus there are some designs that use analog electronics for compute, and it reduces power.
CyberDildonics 2y ago
PIM - processing in memory? I don't think this is something that actually exists in a working competitive state. I also don't think there is "more attention" by anyone actually working on cpus. You don’t burn active power? What does this mean?
- gdiamos 2y ago
  SSDs are 3D with high stacking. They retain data without burning power, unlike SRAM. What if you put some of these 3D transistors tightly integrated with a 3D SSD and power gated them? It seems like you would beat the memory wall. Obviously manufacturing that is beyond us today.
  - CyberDildonics 2y ago
    It seems like you would beat the memory wall. I don't know what this is supposed to mean. Why would putting coprocessing somewhere outside of the CPU be better than just sending data to storage?
    - gdiamos 2y ago
      It takes a lot of energy to move data
      - CyberDildonics 2y ago
        Says who? Also wouldn't this idea just be moving data before it's fully processed? Why wouldn't the intermediate data be bigger? Also "a lot" isn't a number and what are you comparing it to?
        gdiamos 2y ago
        Says the hotchips keynote - https://www.youtube.com/watch?v=rsxCZAE8QNA&t=2480s https://www.youtube.com/watch?v=rsxCZAE8QNA&t=2480s - data that is moved is about 100x higher power than data that is local You have a good point about intermediate data. This would not apply to all algorithms.
        CyberDildonics 2y ago
        You're talking about processing data, then moving data and processing it somewhere else, which is the opposite of the locality that presentation is saying valuable.

It's mainly as a way to overcome the bandwidth limits between memory and CPU. It will increase the heat density of the memory, but there's room to play there. Plus there are some designs that use analog electronics for compute, and it reduces power.

CyberDildonics 2y ago

PIM - processing in memory? I don't think this is something that actually exists in a working competitive state. I also don't think there is "more attention" by anyone actually working on cpus. You don’t burn active power? What does this mean?

gdiamos 2y ago
SSDs are 3D with high stacking. They retain data without burning power, unlike SRAM. What if you put some of these 3D transistors tightly integrated with a 3D SSD and power gated them? It seems like you would beat the memory wall. Obviously manufacturing that is beyond us today.
- CyberDildonics 2y ago
  It seems like you would beat the memory wall. I don't know what this is supposed to mean. Why would putting coprocessing somewhere outside of the CPU be better than just sending data to storage?
  - gdiamos 2y ago
    It takes a lot of energy to move data
    - CyberDildonics 2y ago
      Says who? Also wouldn't this idea just be moving data before it's fully processed? Why wouldn't the intermediate data be bigger? Also "a lot" isn't a number and what are you comparing it to?
      - gdiamos 2y ago
        Says the hotchips keynote - https://www.youtube.com/watch?v=rsxCZAE8QNA&t=2480s https://www.youtube.com/watch?v=rsxCZAE8QNA&t=2480s - data that is moved is about 100x higher power than data that is local You have a good point about intermediate data. This would not apply to all algorithms.
        CyberDildonics 2y ago
        You're talking about processing data, then moving data and processing it somewhere else, which is the opposite of the locality that presentation is saying valuable.