Thunderbolt is basically external PCIe, so this is not so surprising. High speed NICs do consume a relatively large amount of power. I have a feeling I've seen that logo on the board before.
It isn't. There is no sense in which "Thunderbolt is basically external PCIe". Thunderbolt provides a means of encapsulating PCIe over its native protocols, which puts PCIe on the same footing as other encapsulated things like DisplayPort and, for TB4 and later, USB.
I'm surprised you are only getting 20gbit/s. I did not expect PCIe to be be the limiting factor here. I've got a 100gbit cx4 card currently in a PCIe3 X4 slot (for reasons, don't judge) and it easily maxes that out. I would have expected the 25g cx4 cards to be at least able to get everything out of it. RDMA is required to achieve that in a useful way though.
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).
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!
I cannot find anything for less than 285 USD. The blog post gave a price of 174 USD. I have no reason to disbelieve the author, but a bummer to see the current price is 110 USD more!
Does this manufacturer's practice pattern of repackaging data center components (e.g. Mellanox) imply any up and coming product creation opportunities?
I used to have an SFP28 Mellanox card in my home server, but went back to a simple 2.5G Ethernet port for the LAN side. The Mellanox card ran hot and needed an extra fan near it to dissipate the heat. It was cool but there was no real benefit other than occasionally when transferring some large files.
Until motherboards include SFP ports it's probably not worth the effort at all in home setting; external adaptors like the one presented here are unreliable and add several ms of latency.
That is really cool to read. And here I am, still running my home network on a measly 1Gbit Ethernet. I considered upgrading, but the equipment power consumption even when idle makes it an expensive proposition to consider just for fun.
Any idea why ethernet stagnated in terms of speed? There was a time it was so much faster compared to usb. Now even wifi seems to be faster.
Sure one can buy nice ethernet cards and cables, but the reality is that if you grab a random laptop/desktop from best buy and a cable, you are looking at best at a 2.5Gb/s speed.
> Any idea why ethernet stagnated in terms of speed? There was a time it was so much faster compared to usb. Now even wifi seems to be faster.
wifi is not faster.
However ethernet is not as critical as it used to be, even at the office. People like the conveniency of having laptops they can move around. Unless you are working from home, having a dedicated office space is now seen as a waste of space. If the speed of the wifi is good enough when you are in a meeting room or in your kitchen, there is no reason to plug your laptop when you move back in another place, especially if most connections are to the internet and not the local network. In the workplace, most NAS have been replaced by onedrive / gdrive, at home NAS use has always been limited to a niche population: nerds/techies, photographers, music or video producers...
Ha. I got one of the 10G Thunderbolt adapters a several years ago. And eventually started having problems with Zoom calls around noon. With dropped connections and stuttering. Zoom restarts usually fixed the problem.
After it happened 3-4 times, I started debugging. It turned out that we usually get at least a bit of sunlight around noon, as it burns away the morning clouds. And my Thunderbolt box was in direct sunlight, and eventually started overheating.
And a Zoom restart made it fall back onto the Wifi connection instead of wired.
I fixed that by adding a small USB-powered fan to the Thunderbolt box as a temporary workaround. I just realized that it's been like this for the last 3 years: https://pics.ealex.net/s/overheat
> the biggest downside of the PX adapter is that it gets really hot, like not touchable hot. Sometimes, either the network connection silently disappeared or (sadly) my Mac crashed with a kernel panic in the network driver. Apple has assured me that this was not a security issue. Other than that, the PX seems to do the job.
Please forgive me for my ignorance, but are there currently any ways of being able to write data down at that speed? I see 2026 PCIe 5.0 NVMe advertising theoretical 14gb/s but not sure how feasible even that is.
I've had a lot of problems with even 10GbE via Thunderbolt 3/4. Bandwidth-wise it works fine, but latency and jitter are issues. This means that stuff like high-speed cameras that need to be synchronized over Ethernet using Precision Time Protocol (PTP) tend to simply fail with these devices.
> All other 25 GbE adapter solutions I’ve found so far ... have a spinning fan. ... the biggest downside of the PX adapter is that it gets really hot, like not touchable hot. Sometimes, either the network connection silently disappeared or (sadly) my Mac crashed with a kernel panic in the network driver. ... Other than that, the PX seems to do the job
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[ 3.0 ms ] story [ 55.7 ms ] threadhttps://support.apple.com/guide/mac-help/ip-thunderbolt-conn... etc
Edit: forgot is isn't "true" PCIe but tunneled.
I had to do a double-take when it mentioned Kelvin since That is physically impossible.
But this is a cool solution
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 observed.
Small thing: I just checked Amazon.com: https://www.amazon.com/s?k=thunderbolt+25G&crid=2RHL4ZJL96Z9...
I cannot find anything for less than 285 USD. The blog post gave a price of 174 USD. I have no reason to disbelieve the author, but a bummer to see the current price is 110 USD more!
Until motherboards include SFP ports it's probably not worth the effort at all in home setting; external adaptors like the one presented here are unreliable and add several ms of latency.
Sure one can buy nice ethernet cards and cables, but the reality is that if you grab a random laptop/desktop from best buy and a cable, you are looking at best at a 2.5Gb/s speed.
Servers had a reason to spend for the 10G, 25G and 40G cards which used 4 lanes.
There are 10 Gigabit chips that can run off of one PCI-E 4.0 lane now and the 2.5G and 5G speeds are supported(802.3bz).
wifi is not faster.
However ethernet is not as critical as it used to be, even at the office. People like the conveniency of having laptops they can move around. Unless you are working from home, having a dedicated office space is now seen as a waste of space. If the speed of the wifi is good enough when you are in a meeting room or in your kitchen, there is no reason to plug your laptop when you move back in another place, especially if most connections are to the internet and not the local network. In the workplace, most NAS have been replaced by onedrive / gdrive, at home NAS use has always been limited to a niche population: nerds/techies, photographers, music or video producers...
After it happened 3-4 times, I started debugging. It turned out that we usually get at least a bit of sunlight around noon, as it burns away the morning clouds. And my Thunderbolt box was in direct sunlight, and eventually started overheating.
And a Zoom restart made it fall back onto the Wifi connection instead of wired.
I fixed that by adding a small USB-powered fan to the Thunderbolt box as a temporary workaround. I just realized that it's been like this for the last 3 years: https://pics.ealex.net/s/overheat
Made me chuckle.
> All other 25 GbE adapter solutions I’ve found so far ... have a spinning fan. ... the biggest downside of the PX adapter is that it gets really hot, like not touchable hot. Sometimes, either the network connection silently disappeared or (sadly) my Mac crashed with a kernel panic in the network driver. ... Other than that, the PX seems to do the job