Comment by teaearlgraycold
2 days ago
Eventually we'll have machines with unified memory+storage. You'll certainly have to take a bit of a performance hit in certain scenarios but also think about the load time improvements. If you store video game files in the same format they'd be needed at runtime you could be at the main menu in under a second.
At a minimum, we should be able to get everything to DRAM speeds. Beyond that you start to run into certain limitations. Achieving L1 latency is physically impossible if the storage element is more than a few inches away from the CPU.
Most new motherboards do already have the highest throughput M.2 connector very near the CPU.
The most recent desktop I built has it situated directly below the standard formfactor x16 PCI slot.
I think part of the reason why it's so close is also for signal integrity reasons.
2 replies →
> you could be at the main menu in under a second
That would be possible even on spinning harddrives as long as they're already spinning.
The fastest memory can't prevent the real reason games take so long to the menu: company logos. The Xbox can already resume a closed game within a few seconds, loading a simple main menu is trivial in comparison.
The separation into RAM and external storage (floppy disks, magnetic tapes, hard drives and later SSD etc) is the sole consequence of technology not being advanced enough at the time to store all of the data in memory.
Virtual memory subsystems in operating systems of the last 40+ years pretty much do exactly that – they essentially emulate infinite RAM that spills over onto the external storage that backs it up.
Prosumer grade laptops are already easily available, and in 2-3 years there will be ones with 256-512 Gb as well, so… it is not entirely incoceivable that in 10-20 years (maybe more, maybe less) the Optane style memory is going to make a comeback and laptops/desktops will come with just memory, and the separation into RAM and external storage will finally cease to exist.
P.S. RAM has become so cheap and has reached such large capacity that the current generation of young engineers don't event know what a swap is, and why they might want to configure it.
I have a feeling (and it's just a feeling) that many SoC-style chips of the future will abandon Von Neumann Architecture entirely.
It's not that much of a stretch to imagine ultra dense wafers that can have compute, storage, and memory all in one SoC.
First, unify compute and memory. Then, later, unify those two with persistent storage so that we have something like RAM = VRAM = Storage.
I don't think this is around the corner, but certainly possible in about 12 years.
I am also of the opinion that we are heading towards the convergence, although it is not very clear yet what the designs are going to converge on.
Pretty much every modern CPU is a hybrid design (either modified Harvard or von Neumann), and then there is SoC, as you have rightfully pointed out, which is usually modified Harvard, with heterogenuous computing, integrated SIMT (GPU), DSP's and various accelerators (e.g. NPU) all connected via high-speed interconnects. Apple has added unified memory, and there have rumours that with the advent M5 they are going to change how the memory chips are packaged (added to the SoC), which might (or might not) lay a path for the unification of RAM and storage in the future. It is going to be an interesting time.