The M1's memory is LPDDR4X-4266 or LPDDR5-5500 (depending on the model, I guess?) which is about double the frequency of the memory in the Intel Macs.
Apparently, this alone seems to account for a lot of the M1's perf wins — see e.g. the explanation under "Geekbench, Single-Core" here: https://www.cpu-monkey.com/en/cpu-apple_m1-1804
Bleeding-edge-clocked DRAM is a lot more costly per GB to produce than middle-of-the-pack-fast DRAM. (Which is weird, given that process shrinks should make things cheaper; but there's a DRAM cartel, so maybe they've been lazy about process shrinks.)
Apparently DRAM and NAND do not shrink as well because in addition to transistors in both cases you need to store some kind of charge in a way that is measurable later on - and the less material present, the less charge you are able to store, and the harder it is to measure.
That's a high frequency, but having two LPDDR chips means at most you have 64 bits being transmitted at a time, right? Intel macs (at least the one I checked), along with most x86 laptops and desktops, transfer 128 bits at a time.
> Apparently, this alone seems to account for a lot of the M1's perf wins — see e.g. the explanation under "Geekbench, Single-Core" here
That's a vague and general statement that site always says, so I wouldn't put much stock into it.
Am I missing something?
Mind you with 16Gb, Docker won’t be that useful.
Then again I would have expected them to have discussed it as much as the video editing.
I am guessing that they’d need a M2 type chipset for accessing more RAM for that. Or maybe they’ve got a new way to do virtualisation since that is such a key thing these days.
Edit: thanks for pointing that out though, that’s why I mentioned it
https://developer.apple.com/documentation/virtualization
https://news.ycombinator.com/item?id=23922846
And the mentioned Virtio here:
http://www.linux-kvm.org/page/Virtio
How well this fits in with current virtualisation would be interesting to find out; I guess this will be for a later version of Big Sur, with a new beefier M2 chip.
On iOS they can get away with less RAM than the rest of the market by killing apps, relaunching them fast, and having severely restricted background processes. On Mac they won't have that luxury. At least they have fast SSDs to help with big pagefiles.
With the heterogeneous memory, your 8GB computer doesn't even have its whole 8GB of main system memory.
When the touchbar MBP launched in 2016 people were already complaining that it couldn't spec up to 32GB like the competition. Four years later, and it's still capped at 16GB.
Hopefully they can grow this for next year's models.
The difference was incredible
Have you looked at Activity Monitor to see what is butchering your memory?!
Second: web browsers, which can easily grab 5-10GB by themselves or even more if RAM is available.
So in other words: everything.
For example Chrome will scale the amount of RAM it reserves based on how much you have available.
Cache is excluded from just about any tool that shows RAM use, at least on desktops. If the ram shows as in use, the default assumption should be that it's in active use and/or wasted, not cache/preloading.
> For example Chrome will scale the amount of RAM it reserves based on how much you have available.
Which features are you thinking about that reserve ram, specifically? The only thing I can think of offhand that looks at your system memory is tab killing, and that feature is very bad at letting go of memory until it's already causing problems.
I'm not a mac user but that seems ridiculous. I'd be investigating what's hogging it all.
I have chrome, Firefox, photoshop, vs code, docker and a few other things running. As a kid I had to manage RAM. As an adult, I buy enough RAM to not need to think about it.
I was committed to buying an M1 on day one. I won’t buy a machine with only 16gb of RAM.
I'm betting this is due to Thunderbolt controller and PCIe lane capacity. They couldn't do four Thunderbolt ports with the M1 SoC, so they dropped the ports. Having four USB-C ports but only two supporting Thunderbolt would be a more obvious step back from the previous MacBook Pro. This way people can just blame it on Apple doing Apple things, instead of seeing a technical limitation.
Yes, it seems crazy, yes it's a lot of ram, but I like to be able to run VMs locally and not have to boot up instances on AWS (insert provider of choice), I like to keep tabs open in my browsers, I like not to have to close apps when I'm using them and I like my computer to be snappy. 64 GB allows that 16 doesn't, 32 barely does.