zimmie

xp17 said:

zimmie said:

So at least we know the SSD on the Mac Pro will still be replaceable, like it is today. There wouldn't be any reason to have a non-user-accessible flash cart if they didn't plan to make a replaceable one.

I wonder if anyone has compared the pinout of the Mac Studio's flash carts to the flash carts in the iMac Pro and Mac Pro. The Mac Studio carts are shorter, so maybe the notch is moved to make them physically incompatible.

I haven't yet been able to find a report of anybody who has changed the flash carts in an iMac Pro, but I bet it's the same process as the Mac Pro. Shut down, pull the SSDs, restore the T2 using Apple Configurator. The Mac Studio and new Mac Pro will probably be the same once Apple Configurator is updated for the new Mac Pro.

You're wrong. This is not SDSD. it's just NAND memory modules. All electronics, drivers are on the motherboard. This cannot be changed

alexjenn said:

So, what happen when someone uses an old Mac stuck with an old and unpatchable OS?

programmer said:

zimmie said:
On the topic of RAM, there's nothing inherent in the M1's design which precludes off-package RAM. They have a RAM controller on the chips, and the RAM controller is shared between CPU and GPU cores, but there's no fundamental reason the RAM couldn't be in DIMMs. Apple just hasn't chosen to do that. They might do so with the Mac Pro, or they might not. I don't see them doing a tiered memory structure, though. They just went to significant lengths to do away with NUMA concerns on the M1 Ultra.
With the introduction of the Mac Studio, I wouldn't be surprised to see the Mac Pro go primarily rackmount. Very few people need more computing power than the Mac Studio offers at their desks. Almost everyone who does need more computing power is in an environment where they can rack the computer in a closet. For example, recording studios, film studios, scientific labs, and so on all have 19" rack space for other equipment, so putting specialist workstations in there isn't a stretch. That said, rackmount would mostly be relevant for a box with several full-height, full-length PCIe slots (e.g., to add hardwired audio and video inputs), and I'm not yet convinced Apple is interested in that at all. They might say the future is a rackmount interface which connects to the system via Thunderbolt. I'd be curious to know what they have seen the current rackmount Mac Pro doing.

The in-package memory has much tighter timing tolerances because the memory configuration is fixed, lower signal driver power levels, and at very short distances.  I would imagine that their memory controller takes full advantage of those facts, and cuts a lot of the complicated corners that dealing with DIMM slots creates.  So, I disagree:  I do not think their memory controller could support out-of-package memory without some serious work, and it would represent a large power increase and performance impact.

What I suggested isn't a software-visible tiered memory structure.  It is just an alternative fast backing-store for the existing virtual memory system that all software currently works with (currently backed by flash memory).  Implementing this would require no changes to the M1 architecture and very little OS change.  The Mac Pro has a very small market (especially with the Mac Studio now taking a chunk of it), so custom work to support it doesn't make a lot of sense for Apple.  That's a big reason why I think the M1 Ultra is what we will see in the Mac Pro.  And probably just one of them as going multi-chip is a lot of specialized added hardware design work that I don't think they want to do.

The M1 Ultra has a pretty amazing amount of compute, after all.  Bump the clock rate a little and you give it a small edge over the Mac Studio.

A rack mountable full-sized case (but still a desktop workstation) which can hold lots of extra drives, memory, and PCIe cards would differentiate it from the Mac Studio.  

I doubt they will do this, but one thing they could do fairly easily in such a form factor is put the M1 Ultra motherboard itself on a PCIe card so one case could hold multiple of them (the case becomes just a PCIe backplane then).  How such a machine would be used becomes more challenging though and would take them away from their preferred programming model of a single shared memory space for many CPU/GPU cores.  Without a lot of OS work such a machine would look like several Macs on a high speed network... has some uses, but gets pretty obscure and way out of the consumer space.  Then again, it is the "Mac Pro" so who knows?