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

eclecticlight.co

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

#211

Earlier quoted context omitted.

Pretty much this. At the moment, I am trying to sort this out for my parents who bought a MacBook Air to replace a 12" MacBook and want to know if it is still possible to use a pair of 23" 1080p HP displays with it. They don't care about resolution so much, nor does my brother who tested this setup with his 2017 MacBook - bad keyboard and all. (On that front, last I heard, there was a hidden preference for non-HiDPI…

At least one person at work is using something like that to drive two displays from the M1, so I suspect it can be made to work well enough.

I have two external monitors on my M1 Air. The "main" one is connected via hdmi and runs at 120Hz, and another one is connected via DisplayLink compatible adapter which is connected via usb to the same usb hub as the first monitor. That hub is then connected with two usb type-c connectors+cables to the laptop. It works quite fine. There is a small caveat though. The monitor connected with DisplayLink has a very small input lag, but for light work it works just fine. I would not tolerate it for a main monitor (some people would I guess), but it defintely is much better than not having a monitor.

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

#212
USB-C seems to be hit & miss in general, it not only depends on the connector but also the cable and what's on the other side. I use my M1 with a Lenovo USB-C dock an theoretially it's capable of piping 4k at 60 Hz to my monitor, but in order for that to work I'd need to buy cables that cost half as much as the dock, so I just plug the HDMI cable directly into the Macbook (and am thankful they included an HDMI port at all). Also, you have to know which USB-C port to plug stuff into as they don't seem to be equal in terms of functionality, or maybe it's just the cable? In any case they're not marked differently. But yeah, first world problems.

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

#213

Quoted post unavailable.

> Even software that is directly ported has trouble because M1 tile memory cache is designed for minimal tasks, not heavy computing, and computationally heavy software has to be re-written from scratch to optimize it for the platform. Huh? I have no idea what this is supposed to mean. Tile based memory refers to the GPU, and you don't have to rewrite your GPU software from scratch, that's insane? That's what Metal is…

I think they mean that GPU applications that are not optimized for TBDR may experience reduced performance.

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

#214
post #79

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.

I think it would be fine IF the higher numbers were universal supersets of previous versions of USB. 'i don't care what this version is it's the highest" seems fair. At least the "universal" aspect applies over time. It's the apples of the world who seem to be on divergent fork with superior and inferior types of functionality that really disrespect the "universal" moniker... While also ambiguating exactly which USB…

Apple has always been 'vague' in their material about what you're getting, exactly. Often a lot of digging, and / or research needs to be done.

Don't start me on the Pro / Max / Ultra... which one is the best? Which one _should_ be the best, given the moniker of 'maximum'?

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

#215
post #111
post #60

Earlier quoted context omitted.

What sucks, however, is that you can transfer 1TB to a USB drive correctly, and then finally have a bit-error that spoils the entire transfer and might even corrupt your drive. Happened to me several times during testing on different machines and with different cables and drives (luckily no real data was lost, but USB is now sort of banned from my office for use with external harddrives). Any sane protocol would be a…

Use a filesystem that does end-to-end error detection and correction. I use ZFS on all of my USB drives (even "real" SATA and M.2 SSDs via adaptors) and it frequently finds checksum errors (and thanks to the design of ZFS, is able to completely recover without any risk of further corruption).

Isn't any filesystem that runs on top of a SSD or flash drive at risk from the SSD/flash drive controller corrupting the disk or making it inaccessible, when the volume is not cleanly unmounted?

I can remember losing a USB drive that way, even though it was using a journaling filesystem.

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

#216

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.

The USB-IF is a group consisting of implementers (IF = Implementers Forum) and obviously it's more profitable for them if they can put "USB 3.2 support" on the box, but keep using the same hardware (newer and more capable => more expensive => lower profit). So in a perverse way - the USB-IF actually has a financial incentive to keep making more confusing standards, because consumer confusion can be exploited for higher profitability.

This is why it's baffling to me that the EU wants to hand this particular forum a legal monopoly on the connector and protocol standards we all have to use in our devices, and that people actually think that's a super good idea that will work out well.

At best they're an incredibly logjammed body, the only reason Lightning exists is because USB-IF couldn't settle on a replacement for USB Micro-B and after years of debate and still no progress Apple finally just went around them (which lit a fire under them to pass USB-C finally). Kinda similar to the way VESA waffled on the Adaptive Sync draft standard for years and years until NVIDIA just finally went around them and implemented their own VRR sync standard, which finally gave the other members the incentive to shit and get off the pot.

Even still, the only thing they could agree on was a "kitchen sink" standard that's ridiculously cumbersome and expensive and complicated - USB-C cables require hand-termination and will simply always be more expensive than an equivalent machine-assembled lightning or micro-B cable [0], and most cables (and for that matter, most devices/connectors/etc) don't support the functional capabilities promised by the USB-C advocates. One cable doesn't do everything, and most devices and cables in fact won't do most of the things that USB-C is capable of delivering. The standard is in fact so complex that most cables get it wrong to a dangerous degree (devices can be destroyed by improperly-implemented cables) as one of Google's engineers discovered [1] when he started systematically testing cables for standards compliance. And the negotiation is more complex and expensive to implement as well, even if you're only doing a low-capability device. There are just fundamental problems with trying to have a standard that covers everything between 1.5 mbit HID devices and 40 gbit PCIe tunneling in the exact same standard and connector and cable (it sounds absurd to even say that).

These standards bodies often don't work very well, and handing them the keys to the kingdom basically guarantees at least some degree of slowed progress and increase in market deadweight. If we mandated that everyone adopt VESA and that HDMI would be illegal to sell in the EU - that would produce similar deadweight loss in the display connection standards as well. Etc etc. IMO while you do want standards - you want at least two standards bodies so that you don't end up in the USB-IF situation where one of them has a legal monopoly.

(not that that's a panacea - by the way - Apple also is advertising HDMI 2.1 and yet they only support 4K60 [2], they are another one of the companies who took advantage of the HDMI Consortium's new standards branding where they do the same thing as USB and HDMI 2.1 can actually be a rubberstamp reapproval of HDMI 2.0b hardware. [3])

I think a lot of people get really wrapped up in the whole "android vs apple" thing and don't really think about what exactly they're doing, they're just happy "their side" won. But in the long term it's going to be far more difficult to actually get improvements passed, because it's legally impossible to produce innovative products that exist outside USB-IF standards if you want to sell in the EU, and USB-IF just doesn't work at all.

[0] https://www.youtube.com/watch?v=Y1Tmtd51clI

[1] https://arstechnica.com/gadgets/2016/02/google-engineer-find...

[2] https://www.apple.com/apple-tv-4k/specs/ (they actually seem to have rolled back the "HDMI 2.1" advertising on a lot of devices but they missed a few! There is, technically, a footnote however.)

[3] https://www.youtube.com/watch?v=qo9Y7AMPn00

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

#217
post #170
post #60

Earlier quoted context omitted.

What sucks, however, is that you can transfer 1TB to a USB drive correctly, and then finally have a bit-error that spoils the entire transfer and might even corrupt your drive. Happened to me several times during testing on different machines and with different cables and drives (luckily no real data was lost, but USB is now sort of banned from my office for use with external harddrives). Any sane protocol would be a…

This doesnt actually happen (single bit errors getting thru). USB 3.1 data is protected with https://en.wikipedia.org/wiki/Cyclic_redundancy_check#CRC-32... , same CRC as the one used in Ethernet. https://www.rroij.com/open-access/implementation-of-link-lay... USB 3 uses CRC-16, still more than good enough for single bit flips.

Interesting. Perhaps it was more than one bit-flip then ...

Anyway, it still sucks that I couldn't find the exact reason for the error in the logs.

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

#218
post #147

Earlier quoted context omitted.

Isn't the Mac M1 mini $699?

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.

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

#219

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.

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

#220
post #219

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.

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