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Comment by adastra22 | Hacker News Reader

Yeah both RAM and storage aren’t comparing apples to apples (heh) when compared as people often do. If you double the storage on your MacBook, Apple doubles the number of storage chips, with dedicated pcie lanes to each. Since it internally operates with something like RAID0, you also get double the speed.

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The NVME controller on Apple Silicon is not PCI-based, so there are no pcie lanes going to the storage chips at all.

Do we know that for sure? There are I/O lanes being allocated whatever the exact technology being used is. I just don’t see why they’d reinvent the wheel here.

Yes, the Asahi Linux reverse engineers said in their commit message for the Linux apple-nvme driver:

“Add a driver for the NVMe storage controller integrated on Apple SoCs. This NVMe controller isn't PCI based and deviates from the NVMe standard in its implementation of the command submission queue and the integration of an NVMMU that needs to be managed. This commit tweaks the core NVMe code to support the linear command submission queue implemented by this controller. But setting up the submission queue and managing the NVMMU controller is handled by implementing the driver ops that were added in an earlier commit.“

I agree for RAM, but not for flash storage. The competition usually has as-good or even better flash throughput and IOs/second.

The reason people are aggrieved by Apple’s storage upgrade prices is that you can usually buy a high-end, entire NVMe device of a given capacity for less than Apple charges just for the upgrade to that capacity, and the NVMe will be as fast or faster than Apple’s offering.

Not a very relevant point - the difference between 500 MB/s and 5 GB/s mass storage is rarely noticeable.

Depends on what you're doing. It's very noticeable for my work.

In my case, software development with C++. It's basically small files and a lot of disk cache.

I’m processing 100’s of GB of information (the whole historical bitcoin blockchain). Enough to not fit in RAM, but the computation I’m running is fast enough to not be CPU bound.

At home I have a desktop rig with multiple TB RAM and a fast server CPU. I would normally ssh into that to run tests with the chain mounted on a /dev/shm partition, which was a pain and only was accessible when I was at home. With my new MacBook Air, the upgraded internal drive is large enough to hold the full historical chain, and streams from disk fast enough to finish a run in comparable time. So now I’m mobile and can work from anywhere, with an entry point laptop replacing a dedicated server! That’s a big change for me.

I recognize not everyone’s tasks are bottlenecks the same way though.

Same here, but processing the entire history of Ethereum instead.

Absolutely. That's why in newer computers with M.2 storage I'm delighted to find the existence of SATA SSD storage in M.2 form factor. Now I don't have to pay NVMe prices any more.

Whereas with Apple, I believe the only choice is NVMe storage. What if I want more but slower SSD storage?

You mean M.2 SATA storage is available cheaper than M.2 NVMe where you live? Over here there are very few options in M.2 SATA form factor and the prices are almost double that of M.2 NVMe, which is really not that suprising given the obviously very much higher volumes of NVMe parts.

Huh I just checked prices again and you are right. I must have remembered wrong. I stand corrected.

I think this is backwards? NVMe should be faster than SATA. I don’t think Apple uses either though. They directly connect the CPU to storage on the SoC. Another commenter above is saying they don’t even use PCIe.

NVMe is faster than SATA. But for my purposes SATA is fast enough; I just hope manufacturers would make SATA SSDs cheaper than NVMe SSDs. But alas that's not the case.

>in newer computers with M.2 storage I'm delighted to find the existence of SATA SSD storage in M.2 form factor Now I don't have to pay NVMe prices any more.

In which year do you live in? New computers haven't been shipping with M2 SATA storage since like ~2018, and SATA SSDs haven't been cheaper than NVME since at least ~2020. NVME has been cheaper than SATA for many years already.

Still much worse than e.g. 2 M.2 slots..

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