> Also, as the OP noted, this setup can support up to 4 Mac devices because each Mac must be connected to every other Mac

I do wonder where this limitation comes from, since on the M3 Ultra Mac Studios the front USB-C ports are also Thunderbolt 5, for a total of six Thunderbolt ports: https://www.apple.com/mac-studio/specs/

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kappuchino 9 hours ago | parent | next [-]

He corrected that in the comment section of the youtube video. Six is actually the maximum amount. He just didn't want to buy another one.

He also published the Benchmarks in Detail and with two/four Macs in Comparison: https://github.com/geerlingguy/beowulf-ai-cluster/issues/17

	▲	re-thc 4 hours ago \| parent [-]
		> He just didn't want to buy another one. Wasn’t it loaned ie didn’t buy any at all? Apple should have loaned enough to flex.

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QuantumNomad_ 15 hours ago | parent | prev [-]

Jeff mentioned in the video that only three of the ports can be used for RDMA. But it’s unclear where that limitation is coming from.

	▲	geerlingguy 14 hours ago \| parent \| next [-]
		From my brief discussion with Exo/Apple, it sounds like that is just a limitation of this initial rollout, but it's not a hardware limitation. Though, I am always leery to recommend any decisions be made over something that's not already proven to work, so I would say don't bet on all ports being able to be used. They very well may be able to though.
	▲	sroussey 14 hours ago \| parent \| prev [-]
		I bet there is one piece of silicon per two ports.