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M1 Thunderbolt ports don’t fully support USB 3.1 Gen 2

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Re: M1 Thunderbolt ports don’t fully support USB 3.1 Gen 2

#221
post #123

Earlier quoted context omitted.

> Why? To solve what exactly? In a sane world, it'd be major.minor, with nothing appended at the end. It's always important to get acquainted with a topic before succumbing to the desire to mindlessly criticize in ignorance. A quick search in Wikipedia shows that USB 3.1 specifies a brand new transfer rate, dubbed SuperSpeed+ transfer mode , " (...)which can transfer data at up to 10 Gbit/s over the existing USB3-typ…

The problem is that the version of the standard is conflated with the version of the port. Here is a better system: 1) The standard has a version number. I would have suggested semver, except that USB will always be backwards compatible within the same physical port, so there's no need for separate major/minor versions. We can just use an incrementing number 1,2,3 etc. 2) The standard gives each physical port layout…

I think you just recreated what the USB Forum is already doing?

The standard as a whole has a version number that increments with the entire standard document.

Port layouts are named A, B, C (and deprecated Micro-A, Micro-B, and Mini-A).

The transfer rates are now named: Gen 1, Gen 2, Gen 1x2, and Gen 2x2. (These names are stupid, but they are names. Gen 1 is all the transport capabilities from USB 1.0 to USB 3.0 {including the now "classic" "superspeed"} and Gen 2 is new starting with USB 3.1 and the even worse named Gen 1x2 and Gen 2x2 are new starting with USB 3.2).

> Obviously this is too long to have on the port itself, so we can stick with just the port type and transfer speed (eg. USB C T2) as the short name.

Marking the port type is redundant because USB has been good about giving every port type a very different physical silhouette. USB A ports look nothing like USB B ports look nothing like USB C ports. (Arguably there are legitimate complaints that USB Micro-A and USB Mini-A had some visual at a glance issues in practice, but you couldn't insert the wrong cable into the wrong port.)

So yeah, that just leaves finding a better way to mark the ports (and cables!) with the transfer speed. "Gen 1", "Gen 2", "Gen 1x1", and "Gen 1x2" all take up a lot of space and maybe aren't the friendliest names to mark on/near ports/cables, but are in theory potentially the only bit of information that ports need to be marked that cannot be assumed by physical port shape. (ETA: Which the USB-IF Marketing names like SuperSpeed 40 and logos like an arc around the number 40 next to the USB symbol are designed to do, though the fact that people don't recognize them and they don't seem common enough in practice that people know they exist is a marketing failure more than a technical failure of the standards.)

Re: M1 Thunderbolt ports don’t fully support USB 3.1 Gen 2

#222

Apple seems to lack the connectivity options competing chips offer, as seen with the limit on external screens on some M1 models and these USB options. It's easy to underestimate the amount of work that external connectors need the chip to do in order to work optimally. It makes sense, of course, as the M1 evolved from a mobile chip with at most one port (USB C if you're lucky) and not a lot of host traffic. I hope A…

> as seen with the limit on external screens on some M1 models (…) I hope Apple fixes these issues soon It’s only the base M1 used in the low-end devices that has limited support for external screens. A MBPro with M1 Max can drive 3x6k (DP1.4) plus 1x4k(HDMI2.0). That seems like more than enough for a laptop. Sounds to me like these issues have already been fixed.

They still don't support DP MST, so you have to use multiple TB ports or use a monitor that supports TB daisy-chaining.

Re: M1 Thunderbolt ports don’t fully support USB 3.1 Gen 2

#223

The inability of the USB standards body to stick to a versioning scheme beggars belief: what in the world could "USB 3.1 Gen 2" possibly mean? Versions are free, why not simply name it "USB 3.2" and make the next one 3.3? "Gen 2" strikes me as the "Essay FINAL (final version 2).docx" of standards revisions.

Then there's the additions made by the Mainboard manufacturers like Asus.

For example, the manual of the Pro WS X570-ACE states that:

"USB 3.2 Gen 1/Gen 2 devices can only be used as data storage only [sic]"

In any case, if you connect a keyboard, mouse or USB hub to them, they'll work.

Re: M1 Thunderbolt ports don’t fully support USB 3.1 Gen 2

#224

Apple seems to lack the connectivity options competing chips offer, as seen with the limit on external screens on some M1 models and these USB options. It's easy to underestimate the amount of work that external connectors need the chip to do in order to work optimally. It makes sense, of course, as the M1 evolved from a mobile chip with at most one port (USB C if you're lucky) and not a lot of host traffic. I hope A…

The fact that I can't connect more than one monitor to my M1-based iMac is a fucking travesty.

I'm an absolute fiend for screen real estate, and I'm not excusing this. It's a reason I didn't jump onto the M1 bandwagon myself when the first models came out.

But I don't see it as nearly reaching the level of being a "fucking travesty", in an era of affordable giant 4K monitors.

At any rate, I'm certainly glad newer models fix this.

Re: M1 Thunderbolt ports don’t fully support USB 3.1 Gen 2

#225
The block size used isn't specified, and that has a significant impact on performance. The exact model drives used aren't specified, but elsewhere in the comments someone references the Crucial X8. With 32KB block sizes, the transfer speed is ~520 MB/s. https://www.anandtech.com/show/16186/crucial-portable-ssd-x6...

Re: M1 Thunderbolt ports don’t fully support USB 3.1 Gen 2

#226
post #25

Earlier quoted context omitted.

Same thing happened with HDMI 2.1, all new features were defined as optional so everyone who only supports the 2.0 feature set can claim HDMI 2.1 compliance

There’s gotta be some lobbying or consulting firm hired by manufacturers that’s using the same strategy between the two standards. The consortiums don’t seem to realize that short-term profits are coming at their expense of their brand.

Why would it come at the expense of long-term profits? The EU has given a legal mandate to USB-IF, you literally are not legally allowed to use anyone else's connection standards. What "profit loss" could possibly occur under a literal government-mandated monopoly requirement?

Display standards aren't quite there yet but HDMI is effectively a monopoly in the living-room space and most people use them for mass-market (low-end) monitors that are the most common. Effectively it might as well be a mandate, especially when DisplayPort comes with much shorter cable lengths/etc that require equipment reconfiguration.

Re: M1 Thunderbolt ports don’t fully support USB 3.1 Gen 2

#227

I wonder whether it's a software or hardware problem? Let's say you have the thunderbolt connector, shouldn't all those supported standards (esp. the usb) then just be software problems? This does not make it easier for apples side, it might still be a huge undertaking, but then it would be upgradable in principle.

I'm wondering the same thing. I guess someone would have to run the same tests on a Mac running Asahi Linux and compare results.

Any ideas of what software to use to measure this on Linux?

Re: M1 Thunderbolt ports don’t fully support USB 3.1 Gen 2

#228

Earlier quoted context omitted.

Why can't you? I am typing this from an M1-MPB with two monitors. I just have 1 through thunderbolt and 1 through the hdmi.

I have a "MacBook Pro (13-inch, M1, 2020)" and I clearly can't have 2 external monitors. I tried everything.

I had a m1 mbp and have used three external monitors from day one. Used a startech 3x4k hub for that. It uses display link - which is sw-based rendering. Worked like a charm for dev work. You likely couldnt tell that from directly connected monitors unless you wanted to push rapidly changing content (like scrolling through logs at 60 screen-heights per second) - then compression would be indeed visible. For work, videos and occasional session of gzdoom it was a-ok.

Re: M1 Thunderbolt ports don’t fully support USB 3.1 Gen 2

#229

Earlier quoted context omitted.

Did you just compare the $700 Mini to a $140 ECS Liva or some $200 HP or Asus Chromebox?

I pretty sure you’re the only one making that comparison.

https://www.phoronix.com/scan.php?page=article&item=apple-ma...

Does a low end desktop trounce the previous generation Macbook Pro?

Re: M1 Thunderbolt ports don’t fully support USB 3.1 Gen 2

#230
post #130

Earlier quoted context omitted.

Maybe we can call it a Universal Serial Bus

I like the idea! Let's start with v1.0, and then just let our PR team decide on the next versions

Nah, we cant go with 1.0. Bad for adoption. Since we can push 10Gbps easily, and maybe up to 40Gbps if we try hard, lets call the first version usb "ultraspeed" and let the marketing guys work with that!
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