Earlier quoted context omitted.
CUDA's just one example; there's a lot of hardware support on the BSDs that Apple doesn't want to inherit.
Why maint other and have baggage ?
macOS 26.2 enables fast AI clusters with RDMA over Thunderbolt
261–270 of 304 posts
Re: macOS 26.2 enables fast AI clusters with RDMA over Thunderbolt
#262dang I wish I could share md tables. Here’s a text edition: For $50k the inference hardware market forces a trade-off between capacity and throughput: * Apple M3 Ultra Cluster ($50k): Maximizes capacity (3TB). It is the only option in this price class capable of running 3T+ parameter models (e.g., Kimi k2), albeit at low speeds (~15 t/s). * NVIDIA RTX 6000 Workstation ($50k): Maximizes throughput (>80 t/s). It is sup…
what about a GB300 workstation with 784GB unified mem?
Re: macOS 26.2 enables fast AI clusters with RDMA over Thunderbolt
#263IS this... good? Why is this something that the underlying OS itself should be involved in at all?
Re: macOS 26.2 enables fast AI clusters with RDMA over Thunderbolt
#264dang I wish I could share md tables. Here’s a text edition: For $50k the inference hardware market forces a trade-off between capacity and throughput: * Apple M3 Ultra Cluster ($50k): Maximizes capacity (3TB). It is the only option in this price class capable of running 3T+ parameter models (e.g., Kimi k2), albeit at low speeds (~15 t/s). * NVIDIA RTX 6000 Workstation ($50k): Maximizes throughput (>80 t/s). It is sup…
what about a GB300 workstation with 784GB unified mem?
Re: macOS 26.2 enables fast AI clusters with RDMA over Thunderbolt
#265Earlier quoted context omitted.
what about a GB300 workstation with 784GB unified mem?
$95K
Now you need to add 8 $5K monitors to get something similarly ludicrous.
Re: macOS 26.2 enables fast AI clusters with RDMA over Thunderbolt
#266does this means an egpu might finally work with macbook-pro or studio?
Re: macOS 26.2 enables fast AI clusters with RDMA over Thunderbolt
#267dang I wish I could share md tables. Here’s a text edition: For $50k the inference hardware market forces a trade-off between capacity and throughput: * Apple M3 Ultra Cluster ($50k): Maximizes capacity (3TB). It is the only option in this price class capable of running 3T+ parameter models (e.g., Kimi k2), albeit at low speeds (~15 t/s). * NVIDIA RTX 6000 Workstation ($50k): Maximizes throughput (>80 t/s). It is sup…
15 t/s way too slow for anything but chatting, call and response, and you don't need a 3T parameter model for that Wake me up when the situation improves
Re: macOS 26.2 enables fast AI clusters with RDMA over Thunderbolt
#268Earlier quoted context omitted.
Exactly: The AI appliance market. A new kind of home or small-business server.
I’m expecting Apple to release a new Mac Pro in the next couple years who’s main marketing angle is exactly this
I think Apple is done with expansion slots, etc.
You'll likely see M5 Mac Studios fairly soon.
Re: macOS 26.2 enables fast AI clusters with RDMA over Thunderbolt
#269Earlier quoted context omitted.
to the point that I had to pull an extra circuit... but tri phase so good to go even if I would like to go bigger. I've limited power consumption to what I consider the optimum, each card will draw ~275 Watts (you can very nicely configure this on a per-card basis). The server itself also uses some for the motherboard, the whole rig is powered from 4 1600W supplies, the gpus are divided 5/5/4 and the mother board is…
What pcie version are you running? Normally I would not mention one of these, but you have already invested in all the cards, and it could free up some space if any of your lanes being used now are 3.0. If you can afford the 16 (pcie 3) lanes, you could get a PLX ("PCIe Gen3 PLX Packet switch X16 - x8x8x8x8" on ebay for like $300) and get 4 of your cards up to x8.
So that switch would probably work but I wonder how big the benefit would be: you will probably see effectively an x4 -> (x4 / x8) -> (x8 / x8) -> (x8 / x8) -> (x8 / x4) -> x4 pipeline, and then on to the next set of four boards.
It might run faster on account of the three passes that are are double the speed they are right now as long as the CPU does not need to talk to those cards and all transfers are between layers on adjacent cards (very likely), and with even more luck (due to timing and lack of overlap) it might run the two x4 passes at approaching x8 speeds as well. And then of course you need to do this a couple of times because four cards isn't enough, so you'd need four of those switches.
I have not tried having a single card with fewer lanes in the pipeline but that should be an easy test to see what the effect on throughput of such a constriction would be.
But now you have me wondering to what extent I could bundle 2 x8 into an x16 slot and then to use four of these cards inserted into a fifth! That would be an absolutely unholy assembly but it has the advantage that you will need far fewer risers, just one x16 to x8/x8 run in reverse (which I have no idea if that's even possible but I see no reason right away why it would not work unless there are more driver chips in between the slots and the CPUs, which may be the case for some of the farthest slots).
PCIe is quite amazing in terms of the topology tricks that you can pull off with it, and c-payne's stuff is extremely high quality.
Re: macOS 26.2 enables fast AI clusters with RDMA over Thunderbolt
#270Earlier quoted context omitted.
Which would almost be great, if the M3 Ultra's GPU wasn't ~3x weaker than a single 5090: https://browser.geekbench.com/opencl-benchmarks I don't think I can recommend the Mac Studio for AI inference until the M5 comes out. And even then, it remains to be seen how fast those GPUs are or if we even get an Ultra chip at all.
Again, memory bandwidth is pretty much all that matters here. During inference or training the CUDA cores of retail GPUs are like 15% utilized.