4 ms·

Laptops with iGPUs are pretty normal, no? (And common on desktops too)

by fulafel 6y ago

masklinn 6y ago
iGPU doesn't mean unified memory.
- chungus_khan 6y ago
  For modern ones it does.
  - jakeva 6y ago
    Can you give an example outside the M1 Macbooks?
    - chungus_khan 6y ago
      Intel iGPUs since gen7, AMD iGPUs since Kaveri. Most laptops have one of these.
      - bhewes 6y ago
        I run my Intel GPU for a message screen. It is i7-9700k and has uniform memory.
      - fulafel 6y ago
        Yep. AMD called it hUMA from 2013 or so when they started marketing it (eg https://www.tomshardware.com/news/AMD-HSA-hUMA-APU,22324.html https://www.tomshardware.com/news/AMD-HSA-hUMA-APU,22324.htm...)
larkost 6y ago
I don't know about the latest Intel integrated GPUs, but for the original ones it was not a unified memory arrangement. Rather the integrated GPU used a dedicated chunk of main memory. It was the same banks of memory, but was treated as separate. If you wanted a texture to appear on-screen, then it had to be moved from the normal pool of memory to the one reserved for the GPU. This reserved pool of memory was even hard-set at boot time, and usually the size of it was determined based on the amount of total memory (for example at one point MacBooks with 4GiB of memory allocated 1GiB for memory, ones with 8GiB allocated 2GiB). What it sounds like Apple has done here is heavily blur those lines. One example would be to load a texture into a memory location, make a change with the CPU, then let the GPU do some modifications, check something with the CPU, then apply it to some shape and display it. On current systems that would mean multiple copy operations of that texture back and forth between segments of memory (across the PCI bus on a dedicated card). Here that might all be done with no copies at all (just handoffs).
- fulafel 6y ago
  > On current systems that would mean multiple copy operations of that texture back and forth between segments of memory This is not the case, as expanded in sibling threads.

Laptops with iGPUs are pretty normal, no? (And common on desktops too)

masklinn 6y ago

iGPU doesn't mean unified memory.

chungus_khan 6y ago
For modern ones it does.
- jakeva 6y ago
  Can you give an example outside the M1 Macbooks?
  - chungus_khan 6y ago
    Intel iGPUs since gen7, AMD iGPUs since Kaveri. Most laptops have one of these.
    - bhewes 6y ago
      I run my Intel GPU for a message screen. It is i7-9700k and has uniform memory.
    - fulafel 6y ago
      Yep. AMD called it hUMA from 2013 or so when they started marketing it (eg https://www.tomshardware.com/news/AMD-HSA-hUMA-APU,22324.html https://www.tomshardware.com/news/AMD-HSA-hUMA-APU,22324.htm...)

larkost 6y ago

I don't know about the latest Intel integrated GPUs, but for the original ones it was not a unified memory arrangement. Rather the integrated GPU used a dedicated chunk of main memory. It was the same banks of memory, but was treated as separate. If you wanted a texture to appear on-screen, then it had to be moved from the normal pool of memory to the one reserved for the GPU. This reserved pool of memory was even hard-set at boot time, and usually the size of it was determined based on the amount of total memory (for example at one point MacBooks with 4GiB of memory allocated 1GiB for memory, ones with 8GiB allocated 2GiB). What it sounds like Apple has done here is heavily blur those lines. One example would be to load a texture into a memory location, make a change with the CPU, then let the GPU do some modifications, check something with the CPU, then apply it to some shape and display it. On current systems that would mean multiple copy operations of that texture back and forth between segments of memory (across the PCI bus on a dedicated card). Here that might all be done with no copies at all (just handoffs).

fulafel 6y ago
> On current systems that would mean multiple copy operations of that texture back and forth between segments of memory This is not the case, as expanded in sibling threads.