5 ms·

Why do we have to go below 10nm at all? We'll have hard physics limitations. Can't we improve on other frontiers? Say more cache?, better design ? More cores?

Why do we have to go below 10nm at all? We'll have hard physics limitations. Can't we improve on other frontiers? Say more cache?, better design ? More cores? Etc. I don't know.

zanny 9y ago
Making features smaller is far and away the most cost efficient way to make processors faster. It is also relevant to remember fan size and processor design are at least two independent divisions in the same company (Intel, Samsung) and are often two separate companies (AMD, TSMC). Its not like the chip makers arent investing engineers in design.
- atomicnumber1 9y ago
  I see. I wonder what there strategy would be like? To double the efforts in reducing fab size or in other factors.
ghettoimp 9y ago
We can of course do both, and there is a lot of work on improving the designs. But scaling down the transistor size is generally a wonderful thing: smaller transistors use less power, produce less heat, and you can fit way more of them in the same area (which enables things like larger caches, etc.)
- atomicnumber1 9y ago
  ok so I see that reducing fab size gives lot of benefits and they have steadily done so for past couple of decades. In doing so maybe they overlooked on design or other factors? And now that we've hit the wall on fab sizes (purportedly), maybe they can double their efforts on other factors.
  - T-A 9y ago
    That reminds me of this talk from 2013: https://www.youtube.com/watch?v=JpgV6rCn5-g https://www.youtube.com/watch?v=JpgV6rCn5-g The gist of it, as I remember it, is that radical design ideas were a bad investment while Moore's law ruled, because they were likely to be outperformed by simply shrinking the standard architecture; after Moore, design gains in importance, but don't expect anything like the performance improvements of the past half century.
    - atomicnumber1 9y ago
      Makes sense. Thanks for the video.
  - ghettoimp 8y ago
    I think there really is quite a lot of innovation going on under the radar in the SoC space. Phones now have “neural engines” and all kinds of image-related processors for their cameras. Desktop CPUs come with integrated GPUs and there’s a lot of memory system consequences of that...
- deepnotderp 9y ago
  Dennard scaling has been dead for a while, smaller transistors don't necessarily by default use less power anymore.
tremon 9y ago
Probably the #1 area that can produce results is avoiding/conquering the processor-memory gap: while processor performance has been growing exponentially, memory (bandwidth) performance has basically grown linearly. There is now a factor 1,000 difference between processor/memory speeds compared to 1980. One of the areas that I have much hope for is near-data processing: since processors scale so much better, pretty much every peripheral device already has its own microcontroller. The idea behind NDP is basically to offload some data-heavy processing to the data layer. What if your disk layer could already preselect your data so the database wouldn't have to read and discard so many rows for each query? What if the network controller could evaluate your firewall rules itself, so dropped packets wouldn't have to interrupt the main CPU?
- CountHackulus 9y ago
  So NDP is essentially what Commodore did with their 1541 disk drive. That disk drive had a 6502 in there to complement the 6502 in the actual VIC-20. From what I remember, the IBM System Z mainframes also do this sort of thing and have dedicated IO processors that can decode XML on the fly for you and other fun things like that.
  - jacquesm 9y ago
    Every modern hard drive is a computer in its own right.
    - sliken 9y ago
      Seagate had a cool project where each hard drive ran linux and they used the physical sas cable to run a 2.5 Gbit network (or two actually) per drive. So you could use that as block storage for luster, hadoop, or similar and enable things like direct disk to disk copies. Cool idea, seems unlikely to hit a reasonable price point though.
  - michrassena 9y ago
    As a matter of fact, I think this concept dates at least as far back as the IBM 360. https://en.wikipedia.org/wiki/Channel_I/O https://en.wikipedia.org/wiki/Channel_I/O And you can find similar concepts in a standard PC today. The GPU is an example of offloading a workload to a specialized processor.
Gravityloss 9y ago
We are software limited also. AFAIK you could design a high level easy to use programming language with high performance vectorized array operations, but such languages at least are not in wide use. By high level I mean something like Ruby where you could specify lambdas for enumerables. But the vm would take care of vectorization and/or parallelization for you.

Why do we have to go below 10nm at all? We'll have hard physics limitations. Can't we improve on other frontiers? Say more cache?, better design ? More cores? Etc. I don't know.

zanny 9y ago

Making features smaller is far and away the most cost efficient way to make processors faster. It is also relevant to remember fan size and processor design are at least two independent divisions in the same company (Intel, Samsung) and are often two separate companies (AMD, TSMC). Its not like the chip makers arent investing engineers in design.

atomicnumber1 9y ago
I see. I wonder what there strategy would be like? To double the efforts in reducing fab size or in other factors.

ghettoimp 9y ago

We can of course do both, and there is a lot of work on improving the designs. But scaling down the transistor size is generally a wonderful thing: smaller transistors use less power, produce less heat, and you can fit way more of them in the same area (which enables things like larger caches, etc.)

atomicnumber1 9y ago
ok so I see that reducing fab size gives lot of benefits and they have steadily done so for past couple of decades. In doing so maybe they overlooked on design or other factors? And now that we've hit the wall on fab sizes (purportedly), maybe they can double their efforts on other factors.
- T-A 9y ago
  That reminds me of this talk from 2013: https://www.youtube.com/watch?v=JpgV6rCn5-g https://www.youtube.com/watch?v=JpgV6rCn5-g The gist of it, as I remember it, is that radical design ideas were a bad investment while Moore's law ruled, because they were likely to be outperformed by simply shrinking the standard architecture; after Moore, design gains in importance, but don't expect anything like the performance improvements of the past half century.
  - atomicnumber1 9y ago
    Makes sense. Thanks for the video.
- ghettoimp 8y ago
  I think there really is quite a lot of innovation going on under the radar in the SoC space. Phones now have “neural engines” and all kinds of image-related processors for their cameras. Desktop CPUs come with integrated GPUs and there’s a lot of memory system consequences of that...
deepnotderp 9y ago
Dennard scaling has been dead for a while, smaller transistors don't necessarily by default use less power anymore.

tremon 9y ago

Probably the #1 area that can produce results is avoiding/conquering the processor-memory gap: while processor performance has been growing exponentially, memory (bandwidth) performance has basically grown linearly. There is now a factor 1,000 difference between processor/memory speeds compared to 1980. One of the areas that I have much hope for is near-data processing: since processors scale so much better, pretty much every peripheral device already has its own microcontroller. The idea behind NDP is basically to offload some data-heavy processing to the data layer. What if your disk layer could already preselect your data so the database wouldn't have to read and discard so many rows for each query? What if the network controller could evaluate your firewall rules itself, so dropped packets wouldn't have to interrupt the main CPU?

CountHackulus 9y ago
So NDP is essentially what Commodore did with their 1541 disk drive. That disk drive had a 6502 in there to complement the 6502 in the actual VIC-20. From what I remember, the IBM System Z mainframes also do this sort of thing and have dedicated IO processors that can decode XML on the fly for you and other fun things like that.
- jacquesm 9y ago
  Every modern hard drive is a computer in its own right.
  - sliken 9y ago
    Seagate had a cool project where each hard drive ran linux and they used the physical sas cable to run a 2.5 Gbit network (or two actually) per drive. So you could use that as block storage for luster, hadoop, or similar and enable things like direct disk to disk copies. Cool idea, seems unlikely to hit a reasonable price point though.
- michrassena 9y ago
  As a matter of fact, I think this concept dates at least as far back as the IBM 360. https://en.wikipedia.org/wiki/Channel_I/O https://en.wikipedia.org/wiki/Channel_I/O And you can find similar concepts in a standard PC today. The GPU is an example of offloading a workload to a specialized processor.

Gravityloss 9y ago

We are software limited also. AFAIK you could design a high level easy to use programming language with high performance vectorized array operations, but such languages at least are not in wide use. By high level I mean something like Ruby where you could specify lambdas for enumerables. But the vm would take care of vectorization and/or parallelization for you.