Maybe motherboards should stop coming with dimms and use the apple approach to get great bandwidth and latency and come in 16, 32, and 64GB varieties by soldering LPDDR4x on the motherboard.
Cite your number please. Anandtech measured M1's memory latency at 96ns, worse than either a modern Intel or AMD CPU: "In terms of memory latency, we’re seeing a (rather expected) reduction compared to the A14, measuring 96ns at 128MB full random test depth, compared to 102ns on the A14."
https://www.anandtech.com/show/16252/mac-mini-apple-m1-teste...
vs. "In the DRAM region, we’re measuring 78.8ns on the 5950X"
https://www.anandtech.com/show/16214/amd-zen-3-ryzen-deep-di...
The reason for this is I like to separate out the cache latency to main memory and the TLB related latencies. Certainly there are workloads that are completely random (thus the term cache thrashing), but there's also many workloads that only have a few 10s of pages active. Doubly so under linux when if needed you can switch to HUGE pages if your workload is TLB thrashing.
For a description of the Anandtech graph you posted see: https://www.anandtech.com/show/14072/the-samsung-galaxy-s10p...
So the cache friendly line is the R per RV prange for the 5950X latencies is on the order of 65ns, the similar line for the M1 is dead on 30ns at around 128KB and goes up slightly in the 256-512KB range. Sadly they don't publish the raw numbers and pixel counting on log/log graphs is a pain. However I wrote my own code that produces similar numbers.
My numbers are pretty much a perfect match, if my sliding window is 64 pages (average swap distance = 32 pages) I get around 34ns. If I drop it to 32 pages I get 32ns.
So the M1, assuming a relatively TLB friendly access pattern only keeping 32-64 pages active is about half the latency of the AMD 5950.
So compare the graphs yourself and I can provide more details on my numbers if still curious.
It would be sort of interesting for Intel/AMD to do something like this where they have 16GB on the CPU and the OS has the knowledge to see it differently from external RAM.
Apple is going to have to do this for their real "Pro" side devices as getting 1TB on the Mx will be a non-starter. I would expect to see the M2 (or whatever) with a large amount of the basic on chip RAM and then an external RAM bus also.
I do wonder how many use cases actually need more then 32GB when you have a low latency NVMe flash with 5+ GB/sec of bandwidth and relatively low latencies. Especially with the special magic sauce that I've seen mentioned related to hardware acceleration for either compressing memory or maybe it was compressing swap.
In any case, I'm not expecting the top of the line for the next releases. Step 1 is low end (mba, mbp13", and mini). Step 2 is mid range, rumored to be a MBP 14.1" and 16 in first half of 2021". After that presumably the mac pro desktop and Imac's "within 2 years". Maybe step #3 will be a dual socket version of step #2 with of course double the ram.
Also from the ASIC yield view it allows for some interesting binning of chips. Let's say the M2 has 32MB on chip plus an off chip memory controller. They could use the ones that pass in the high end, then once that fail a memory test as 16MB on a laptop, etc. Part of keeping ASIC cost down is building the exact same thing and binning the chips in to devices based on yield.
Maybe editing 4K (or in the future, 8K) video might need more?
My brother does a lot of complex thermal airflow simulation, and his workstation has 192GB of RAM, but that is an extreme use case.
And it can handle 8K for 1-2 streams and starts to lag at 4+.
Apple in making the M1 Chip is using some of the Amiga IP circa 1985 that speed up the system where the CPU and GPU etc. share memory. Amiga is shattered into different companies, but if they didn't go out of business they would have made a M1 type chip for their Amiga brand.
This, right here. It also helps that the L1D is a whopping 128 kB and only 3 cycles of load-use latency.
Larger pages mean that performance on memory-mapped small files will suffer... which is a use-case that Apple doesn't normally care about in its client computers.
Larger cache lines mean that highly mulththreaded server loads could suffer from false sharing more often. Again, its a client computer so who cares?
Regarding the definition of "huge": A64FX uses 256B cache lines. Granted its a numerical computing vector machine, but still. Huge covers a lot of ground.
A good old-fashioned 2010-era gaming PC would already get down to around 50 ns levels.
It's definitely really good, but considering it's rather fast RAM (DDR4 4266 CL16) and doesn't have L3 it's not that surprising.
- for big cores, private: 128KB L1D
- for big cores, shared within a cluster: 12MB L2
- system-level cache (shared between everything, CPU clusters, GPU, neural engine...): 16MB
and then you reach RAM.
Each fast core has a L1D of 128KB.
The fast cores have a cluster with 12MB, cache misses to to main memory.
The slow cores have a 4MB L2.
The cache misses from the fast L2 can't quite saturate the main memory systems (I believe it's 8 channels of 16 bits). So when all cores are busy you keep 12MB of L2 for fast, 4MB of L2 for the slow cores, and end up getting better throughput from the memory system since you are keeping all 8 channels busy.
And yeah, it's 128-bit wide LPDDR4X-4266, pretty quick imo.
Same as you can have a storage driver and a smaller nvme.
That's basically what L3 cache is on Intel & AMD's existing CPUs. You could add an L4, but at some point the amount of caches you go through is also itself a bottleneck, along with being a bit ridiculous.
They would be contiguous, not layered.
Similarly, Optane (in dimm form) is basically slow memory, OSs seem to handle it fine. NUMA support seems pretty mature today and handle common use cases well.
With all that said, apple could just add a second CPU to double the ram and cores, seems like a great fit for a Mac Pro.
What operating systems handle NUMA memory through swapping? The only one I'm familiar with doesn't use a swapping design for NUMA systems, so I'm curious to learn more.
I prefer the upgradeability.
The market doesn't care about such niche concerns, but it'll not flip completely overnight.
I like the idea of upgradeability too, but when the trade-off is such great performance, I'm not going to give that up. It would be different if the performance numbers were not as stark.
The open question is how long this performance will be sustained. If it drops off, then concerns like upgradeability make become higher priority (and an opportunity for hardware vendors.)
I am still able to use my Lenovo Thinkpad 510T only because I could easily replace HDD with cheap, stock Samsung EVO SSD and throw more RAM.
The absurdity of Apple approach is that Mac Mini with 512 GB SSD is $200 more expensive than the one with 256 GB. 256 GB for $200 is a crazy price, so Apple basically says: hey, pay us a lot, lot more, so maybe you can use our stuff a bit longer, but, in fact, we try to actively discourage you from doing this, since we want you to buy cheaper model and in two-three years you will need to buy a new fancier model.
But Tim Cook will tell you a lot how much he cares about humanity, environment and CO2 emission. Maybe he will even fly his private jet to some conference to tell people how awful is all that oil & gas & coal industry.
Just because RAM was one of the last holdout of upgradability, does not make it inherently more suitable for upgradability.
The problem is a lack of interest in manufacturing repairable and upgradable hardware. It is simply less profitable.
I do not care all that much abut market either. When I need something it always seems to be there and I do not mind if it is not produced by the biggest guy on the block. If at some point I would not be able to find what I need I'll deal with it but so far it did not happen.
Of course for any CPU workload it's going to be harder on the memory system when you have video going on. Doubly so for a video conference (compression, decompression, updating the video frames, streaming the results, network activity, reading from the camera, etc).
Seems like the apple memory system wouldn't have received as much R&D as it did unless Apple though it was justified. Clearly the speed, performance, and price show that Apple made quite a few good decisions.
There's just nothing driving most people to have more than 8/16GB of RAM and even photo/video editing has been shown to be a breeze on the 8GB MacBook Air.
I wouldn't be surprised to see laptops move to soldered RAM and SSDs.
I beg you to look at memory consumption of those "lightweight" web apps
Why? What's the purpose of artificially limiting performance when one doesn't need the upgradability?
I've, personally, never upgraded the RAM on any system I've built or carried it to a new motherboard with a new socket. I'm absolutely the target audience for this. I would love this increased performance, as long as it wasn't some surprise. Having the extra plastic on the motherboard is literally e-waste for me. Don't touch my PCI-e slots though.
If the SSD in my Macbook/Mac Mini dies, either I can buy a new motherboard, or more likely, a new device. It is not economical nor ecological.
Also, paying 200 dollars for additional 256GB of storage? WTF.
Personally I'd rather have half the latency, more bandwidth, and 4x the memory channels instead of being able to expand ram mid life.
However I would want the option to buy 16, 32, and 64GB up front, unlike the current M1 systems that are 8 or 16GB.
Sure manufacturers might try to charge significantly more than market price for on the motherboard RAM, but it's an opportunity to increase their profit margin and ASP. Random 2x16GB dimms on newegg cost $150 per 32GB. Apparently LPDDR are easier to route to, require less power, and cost less for the same amount of ram. I'd happy pay $500 for a motherboard with 64GB of LPDDR4x-4266. Seems like Asus, Gigabyte, Tyan, Supermicro and friends would MUCH rather sell a $500 motherboard with ram than a $150 motherboard without.
In any case the apple parts are from what I can tell are:
https://www.skhynix.com/products.do?lang=eng&ct1=36&ct2=40&c...
In particular this one:
Greenpeace rated Apple the number 1 most environmentally friendly of the big technology companies.
https://www.techrepublic.com/article/the-5-greenest-tech-com...
Apple devices use a minimum of materials and have industry leading usable lifetimes.
Not buying a new MBP and throwing the old one to children in third world countries qualify as "virtue signaling" now ?
>What matters environmentally is aggregate device lifetime, so you get the most use out of the materials. Apple devices use a minimum of materials and have industry leading usable lifetimes. They are also designed to be highly recyclable.
Reuse and repair is FAR superior to recycle - which actually wastes a lot of energy, in addition to generating e-waste for the parts which are not recycled.
>Greenpeace rated Apple the number 1 most environmentally friendly of the big technology companies.
What good does it do? They are still harming the environment.
There are plenty of ways around that fact.
Preventing repair while changing nothing else generates more e-waste. But that's not what Apple does.
If you prevent repair in order to also do any or all of the following things at the same time enough, the result is less e-waste than if you didn't prevent repair:
- Use less environmentally harmful materials (e.g. on-board sockets, larger PCBs etc)
- Make the device last longer before it needs repair (reliability, longevity)
- Make the device easier to recycle
> Reuse and repair is FAR superior to recycle
It's a good goal, but it's only superior for sure if everything else is able to be kept the same to make it possible.
Some things really are better for the environment melted down and ground down and then rebuilt from scratch. I'm guessing big old servers running 24x7 are in this category: Recycling the materials into new computers takes a lot of energy, but just running the old server takes a huge amount of energy over its life compared with the newer, faster, more efficient ones you could make from the same materials. I would be surprised if not recycling was less harmful than recycling.
> What good does it do? They are still harming the environment.
When saying Apple should change they way they manufacture to be more like other manufacturers for environmental benefit, Apple being rated number 1 tells you that the advice is probably incorrect, as following it would probably cause more environmental harm not less.
If Apple makes devices that last so long, then how come Apple's own extended warranty program generates billions of dollars of revenue? Note that this doesn't include third party repair shops. To me, this indicates a large industry dedicated to repairing Apple products - hardly a niche industry. To me, this indicates that a large amount of Apple devices need repair, something that Apple is hostile to.
Also while AppleCare is easy and convenient for the customer, Apple's "geniuses" do not do board-repair, they simply replace and throw away broken logic boards (which sometimes all they might need is a simple 10 cent capacitor). If that wasn't as bad, they actively prevent other businesses from performing component level repair by blocking access to spare parts.
> I'm guessing big old servers running 24x7 are in this category: Recycling the materials into new computers takes a lot of energy, but just running the old server takes a huge amount of energy over its life compared with the newer, faster, more efficient ones you could make from the same materials. I would be surprised if not recycling was less harmful than recycling.
If that was the case, then of course, we should recycle. Maybe we should have a case-by-case approach depending on specific products? I'm totally willing to go wherever the evidence leads us. As of now pretty much every single environmental organization promotes reuse over recycling for electronics.
>When saying Apple should change they way they manufacture to be more like other manufacturers for environmental benefit, Apple being rated number 1 tells you that the advice is probably incorrect,
I merely accepted the "number one" in good faith at face value. Digging further with a cursory Google search, things seem a lot more nuanced. That being said, I have no idea what "number one" even means without context.
https://www.fastcompany.com/40561811/greenpeace-to-apple-for...
I don't want to back the idea that Apple does make reliable or long-lived devices, although I'm very happy with my 2013 MBP still. I honestly don't know how reliable they are in practice, although they do seem to keep market value for longer than similar non-Apple devices, and they have supported them with software for a long time (my 2013 is still getting updates).
And I would love to be able to add more RAM to my 2013 MBP, which has soldered-in RAM; and I would love if it were easier to replace the battery, and if the SSD were a standard fast kind that was cheap to get replacements for, and if I could have replaced the screen due to the stuck pixel it has due to a screen coating flaw. So I'm not uncritical of the limitations that come with the device.
I'm only disputing your assertion that preventing repair and reuse of parts inevitably generates more e-waste. It's more nuanced than that.
Of course wherever and in whatever ways we can find to repair, reuse and recycle we should.
But there will always be some situations, especially with high-end technology, where repair and reuse needs more extra materials, components, embodied energy and complexity (and subtle consequences like extra weight adding to shipping costs) resulting in a net loss for the environment.
An extreme example but one that's so small we don't think of it is silicon chips. There is no benefit at all in trying to make "reusable" parts of silicon chips. The whole slab is printed in one complex, dense process. As things like dense 3D printing and processes similar to silicon manufacture but for larger object components come online, we're going to find the same factors apply to those larger objects: It's cheaper (environmentally) to grind down the old object and re-print a new one, than to print a more complex but "repairable" version of the object in the first place.
2016 MBP owners will appreciated the joke !
I don't want to back the idea that Apple does make long-lived laptops, only that it's hypothetically possible they do sometimes :-)
My 2013 MBP is still going strong thankfully, I'm very happy with it still after all these years.
Though, somehow, if I trust some argument made here, it would be better for the environment to buy a whole new laptop rather than fix the existing one... Though, I'm not doing it for the environment, I'm just cheap as f*ck.
No, I don't think that argument is being made by anyone.
The argument being made is that to make the laptop more able to have replaceable components could potentially require more environmental costs up front in making that laptop.
I doubt that argument works for the power connector. I suspect that's more to do with making sure Magsafe is really solid, but it might for the battery due to the pouch design instead of extra battery casing, I'm not sure.
There's no question that if you can repair it afterwards you probably should.
By the way, literally all my other laptops either died due to the power connector failing, or I repaired the failing power connector. Sometimes I had to replace the motherboard to sort out the power connector properly, which seems like poor design.
The Apple has been the only one that hasn't failed in that way, which from my anecdote of about 5 laptops says Apple's approach has worked best from that point of view so far. Of course Apple power supply cables keep fraying and needing to be replaced, so it balances out :-)
What you are doing is picking a single marginal factor that can make a difference in rare cases, but is next to irrelevant in practice, and raising that above the total environmental impact of the whole range of devices. That’s just absurd.
I've used the same desktop for the 8 to 6 years, upgrading with STANDARDIZED components over the years, and my laptop from that era still works. Heck, I've got a 18 years old thinpad still working fine.
In the mean time, two MBP died on me. Try again...
Should I take your evaluation in thus, or trust a detailed whole enterprise evaluation by Greenpeace?
It turns out that soldering parts in place makes them less likely to break than a socket whose connections can oxidize or come loose.
The tiny number of devices that can’t be repaired because of soldered components, is dwarfed by the number of devices that never broke in the first place because of soldered components.
You've obvious never heard of MBP BGA chip solder ball cracking and rendering the whole device useless...
In any case, solder ball cracking results from process issues and is a solved problem: https://www.pcbcart.com/article/content/reasons-for-cracks-i...
Certain not something that would be improved with sockets.
https://www.theverge.com/2020/11/19/21573577/intel-nuc-m15-l...