[sudhirj]

All else being equal, yes, but the memory is faster, closer to the chip, has less wiring to go through, and because of vertical integration they can pass by reference instead of copying values internally on the hardware. The last one is big - because all the parts of the SoC trust each other and work together they can share memory withing having to copy data over the bus. That coupled with superfast SSDs means that comparisons aren't Apples to oranges, excuse the pun.

16GB of memory on-die shared by all the components of an SoC is not the same as 16GB made available to separate system components, each of which will attempt to jealously manage their own copy of all data.

[kcartlidge]

I'm not a hardware person, but I do software for a living. Your comment makes things much clearer.

You're saying that the effective difference in having the shared memory is that you get more data passed by reference and not by value at the lower levels?

If that's true, then you get extra throughput by only moving references around instead of shuffling whole blocks of data, and you also gain better resource usage by having the same chunks of allocated memory being shared rather than duplicated across components?

[sudhirj]

That’s how I understand it, yes. I’m not into hardware either, going by engineering side of the event. In the announcement, there some parts shot at the lab/studio, where the engineers explain the chip. Ignore the marketing people with their unlabelled graphs, the engineers explain it well.

But yes, they’re basically saying because this is “unified memory”, there’s no copying. No RAM copies between systems on the SoC, no copies between RAM and VRAM, etc. because the chips are working together, they put stuff on the RAM in formats they can all understand, and just work off that.

[andrekandre]

> because of vertical integration they can pass by reference instead of copying values internally on the hardware.

got any links about that?

[sudhirj]

Going by the engineering explanations in the announcement video. See the segments shot in the “lab” set. They’re actually pretty proud of this and are explaining the optimisations quite candidly.

[andrekandre]

interesting, thanks