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Reliable 25 Gigabit Ethernet via Thunderbolt

kohlschuetter.github.io

51–60 of 133 posts

Re: Reliable 25 Gigabit Ethernet via Thunderbolt

#51

This is an outstanding blog post. Initially, the title did little to captivate me, but the blog post was so well written that I got nerd-sniped. Who knew this little adapter was so fascinating! I wonder if the manufacturer is buying the Mellanox cards used from data center tear-downs. The author claims they can be had for only 20 USD online. That seems too good to be true! Small thing: I just checked Amazon.com: http…

[deleted]

Re: Reliable 25 Gigabit Ethernet via Thunderbolt

#53

Earlier quoted context omitted.

I don't know how to measure the direct power impact on a MacBook Pro (since it's got a battery), but the typical power consumption of these cards is 9 W, not much more than Aquantia 10 GBit cards. Also, if you remember where you saw that logo, please let me know!

JFYI, for measuring power draw, you might be able to use `macmon`[0] to see the total system power consumption. The values reported by the internal current sensor seem to be quite accurate. [0] https://github.com/vladkens/macmon

Speaking of hardware, the RTL8159 (10Gbps) hit the market late last year and is said to consume only about 2–3W. It apparently runs very cool compared to older chips. (Though it would need to be bonded to reach 25Gbps ;-)

Re: Reliable 25 Gigabit Ethernet via Thunderbolt

#54

Ha! Been running these for years on both linux and windows (on lenovo x1 laptops). Using cheap chinese thunderbolt-to-nvme adapters + nvme-to-pcie boards + mellanox cx4 cards (recently got one cx5 and a solarflare x2). Pic of a previous cx3 (10 gig on tb3) setup: https://habrastorage.org/r/w780/getpro/habr/upload_files/d3c... 10gig can saturate full speed, 25G in my experience rarely reaches same 20G as the author ob…

If you don’t mind me asking, what are you using these for? Saturating these seems like it would have reasonably few workloads outside of like cdn or multi-tenant scenarios. Curious what my lack of imagination is hiding here.

Re: Reliable 25 Gigabit Ethernet via Thunderbolt

#55

This is an outstanding blog post. Initially, the title did little to captivate me, but the blog post was so well written that I got nerd-sniped. Who knew this little adapter was so fascinating! I wonder if the manufacturer is buying the Mellanox cards used from data center tear-downs. The author claims they can be had for only 20 USD online. That seems too good to be true! Small thing: I just checked Amazon.com: http…

I saw the blog post last week and immediately bought the last one on that Amazon listing for the original price... hopefully they restock soon!

I'm going to try a couple other fan assisted cooling options, as I'd like to keep the setup reasonably compact.

I just ran fiber to my desk and I have a more expensive QNAP unit that does 10G SFP+, but this will let me max out the connection to my NAS.

Re: Reliable 25 Gigabit Ethernet via Thunderbolt

#56

Earlier quoted context omitted.

I don't know how to measure the direct power impact on a MacBook Pro (since it's got a battery), but the typical power consumption of these cards is 9 W, not much more than Aquantia 10 GBit cards. Also, if you remember where you saw that logo, please let me know!

JFYI, for measuring power draw, you might be able to use `macmon`[0] to see the total system power consumption. The values reported by the internal current sensor seem to be quite accurate. [0] https://github.com/vladkens/macmon

Very nice tip, thank you!

I measure around +11W idle. While running a speed test, I read ca. +15W.

Re: Reliable 25 Gigabit Ethernet via Thunderbolt

#57

Ha! Been running these for years on both linux and windows (on lenovo x1 laptops). Using cheap chinese thunderbolt-to-nvme adapters + nvme-to-pcie boards + mellanox cx4 cards (recently got one cx5 and a solarflare x2). Pic of a previous cx3 (10 gig on tb3) setup: https://habrastorage.org/r/w780/getpro/habr/upload_files/d3c... 10gig can saturate full speed, 25G in my experience rarely reaches same 20G as the author ob…

If you don’t mind me asking, what are you using these for? Saturating these seems like it would have reasonably few workloads outside of like cdn or multi-tenant scenarios. Curious what my lack of imagination is hiding here.

I do media production, and sometimes move giant files (like ggufs) around my network, so 25 Gbps is more useful than 10 Gbps, if it's no too expensive.

Re: Reliable 25 Gigabit Ethernet via Thunderbolt

#58
post #29

Earlier quoted context omitted.

I was hoping somebody would suggest that (and eventually try it out). With TB5, and deep pockets, you might probably also benchmark it against a setup with dedicated TB5 enclosures (e.g., Mercury Helios 5S). TB5 has PCIe 4.0 x4 instead of PCIe 3.0 x4 -- that should give you 50 GbE half-duplex instead of 25 GbE. You would need a different network card though (ConnectX-5, for example). Pragmatically though, you could a…

Too bad Jeff Geerling returned his Mac Studios to Apple. Would be lovely to see how 5x faster RDMA impacts the performance.

25 Gbps isn't all that much. It would be good, but would be below the 40+ Gbps I was getting on the TB5 ring network.

I think where it would show more significant speed up is on the AMD Strix Halo cluster.

Except I haven't been able to get RDMA over Thunderbolt on there to work, so it'd be apples to oranges comparing ConnectX to Thunderbolt on Linux.

Re: Reliable 25 Gigabit Ethernet via Thunderbolt

#60

This is an outstanding blog post. Initially, the title did little to captivate me, but the blog post was so well written that I got nerd-sniped. Who knew this little adapter was so fascinating! I wonder if the manufacturer is buying the Mellanox cards used from data center tear-downs. The author claims they can be had for only 20 USD online. That seems too good to be true! Small thing: I just checked Amazon.com: http…

I believe the author is talking about the OCP (2.0) network card itself, that these adapters internally. The OCP nics are quite cheap compared to pcie - here’s 100GBE for 100! https://ebay.us/m/HMQAph
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