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TrancyGoose

macrumors 6502
Original poster
Jan 13, 2021
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So,

First of all, excuse the amateur.

Thing is, the 2 Thunderbolt ports that I have, are great. But I am very confused.

Now, I have a Netac (Slim) SSD for 1GB, that has an interface 3.2 Gen 2.

Product: https://www.amazon.co.uk/Netac-Exte...netac+ssd&qid=1617750576&s=electronics&sr=1-7

Then I have an ANKED USB C HUB, that has 2 USB-A 3.2 ports and a data port with USB-C.


However, thing is, I tested the SSD I have with the stock cable it came with, via the HUB and plugged directly in to the thunderbolt port with USB C adapter on it. And I am still only getting roughly 400MB read/write on BlackMagic.

So my question is, where are the 40 GB/s speeds plugged in directly to thunderbolt or even 5 GBS that a USB 3.1 would support?
Will anything change if I bought a thunderbolt USB-C to USB-C cable? And who are these crazy speeds for? As far as research I seen, even T7 does roughly 700/900 read-write. It's not that I need 40GBs, I'm trying to understand what would that speed be for, and it just feels that there is more marketing in it than actual necessity.
 

MBAir2010

macrumors 604
May 30, 2018
6,975
6,354
there
I was uploading files to my laptop and was getting 13 GB of music within minutes
this was from a usbC westerndigital G series spin drive (non-ssd) to one of the usbC-whatever outlets on the laptop.
as far as watching i saw 60-50 then some 40 then 60 ?ps with a green curve roller coasteering during the paste process.
i was happy and copied 100 GB of music within that hour
so yes 40GBs can be done, don know if i hit that speed sunday, i think i exceeded that.
 

chabig

macrumors G4
Sep 6, 2002
11,456
9,324
So my question is, where are the 40 GB/s speeds plugged in directly to thunderbolt or even 5 GBS that a USB 3.1 would support?
That Netac drive isn't a Thunderbolt device, so you won't get Thunderbolt speed from it. It's a USB device that supports USB 3.2 Gen 2 speeds "up to 10 Mbps". You're measured speed of about 400 MB/s is good for that device.

Also, you're confusing gigabits per second with gigabytes per second. USB 3.2 Gen 1 supports up to 5 gigabits per second. Gen 2 supports up to 10 gigabits per second. Neither of those come close to 5 gigabytes per second
 

Juicy Box

macrumors 604
Sep 23, 2014
7,580
8,920
Echoing what @chabig said, you need to make sure you are getting the speeds, and units of speeds correctly.

The USB specifications and names can be confusing, but here is a list of the popular standards:

For Thunderbolt:
TB1 Up to 10,000Mbps
TB2 Up to 20,000Mbps
TB3 Up to 40,000Mbps
TB4 Up to 40,000Mbps

USB 1.1 Up to 11Mbps
USB 2 Up to 480Mbps
USB 3.2 Gen1 Up to 5,000Mbps This is the same as USB3.0, and USB3.1 Gen1
USB 3.2 Gen2 Up to 10,000Mbps This is the same as USB3.1, and USB3.1 Gen2
USB 3.2 Gen2x2 Up to 20,000Mbps This is the same as USB3.2
USB 4 Up to 40,000Mbps

Here is FireWire just for comparison:
FW400 Up to 400Mbps
FW800 Up to 800Mbps

These are all theoretical speeds, and due to overhead and other things, real world speeds will be a little bit lower.

This isn't a scientific rule or anything, but a general guide to go by for storage is take the maximum theoretical speed of the port in bits per second, and divide by 10, and that will give you a realistic speed of what you might see for a sequential read of the drive in Bytes per second. This is also assuming that the storage interface type is capable of the maximum speed of the specification used.

For example, the device you posted is USB3.2 Gen2, meaning a max theoretical speed of 10,000Mbps, or 10Gbps. Plus, the device says it is only capable up to 500MBps, so that tells me it might be SATA based storage (6Gbps), and the 400MBps speeds you are getting realistic for USB SATA speeds, or maybe a little lower.

The TB3 port you are using is 40,000Mbps / 10 = about 4,000MBps real world maximum.
The USB3.2 Gen2 drive is 10,000Mbps / 10 = about 1,000MBps real world maximum.
The SATA Storage in the drive is 6,000Mbps / 10 = about 600MBps real world maximum.
Actual speeds observed is 400MBps.

I think your speeds might just be perfectly normal for your drive, and it could be faster, just there could be other things happening that might be slowing down the drive temporarily, such as indexing.

I would double check the link speed and see if it is linking at 10,000Mbps.

The speeds using posted by manufactures are often optimistic and also sequential reads, so keep that in mind.

'm trying to understand what would that speed be for, and it just feels that there is more marketing in it than actual necessity.
There could be all sorts of reasons for different speeds needed/wanted. A general rule is faster is better, but there are downsides with that such as added costs, equipment, heat, etc.

Uses would highly depend on what one is doing with the drive as well, primarily sequential or random reads/writes, budget, used for back up, used for boot drive, etc.

What is it that you do with your drive?
 

Juicy Box

macrumors 604
Sep 23, 2014
7,580
8,920
As far as research I seen, even T7 does roughly 700/900 read-write.
The Samsung T7 uses NVMe SSD inside of it, and is much faster than some slower SSDs such as the one in the drive you have. Being an NVMe, it is capable of saturating the USB3.2 Gen2 bus speed, unlike something slower like SATAIII.

So, with the T7, it would be 10,000Mbps / 10 = about 1,000MBps maximum speed, which is close to the 900MBps read speeds that people are reporting.
 

joevt

macrumors 604
Jun 21, 2012
6,968
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Thing is, the 2 Thunderbolt ports that I have, are great. But I am very confused.
What Mac are you using?

Now, I have a Netac (Slim) SSD for 1GB, that has an interface 3.2 Gen 2.

Product: https://www.amazon.co.uk/Netac-Exte...netac+ssd&qid=1617750576&s=electronics&sr=1-7
1GB? Do you mean 1TB? USB 3.2 gen 2 = USB 3.1 gen 2 = 10 Gbps = 1212 MB/s but usually can't get more than 1000 MB/s because of overhead.
The Netac is limited to 550 MB/s which probably means it's using a SATA III 6G SSD = 6 Gbps. They say 500 MB/s for the drive they use.

Then I have an ANKED USB C HUB, that has 2 USB-A 3.2 ports and a data port with USB-C.

This USB Hub (Anker) is also USB 3.1 gen 2 so it should be able to do 1000 MB/s also.

However, thing is, I tested the SSD I have with the stock cable it came with, via the HUB and plugged directly in to the thunderbolt port with USB C adapter on it. And I am still only getting roughly 400MB read/write on BlackMagic.
400MB/s is kind of low. There might be a problem where the USB device is connecting only at USB 3.0 speed (5 Gbps). Check System Information.app. Make sure the device is connecting at Up to 10 Gbps speed.

So my question is, where are the 40 GB/s speeds plugged in directly to thunderbolt or even 5 GBS that a USB 3.1 would support?
Thunderbolt is 40 Gbps (not 40 GB/s) but can't do much more than about 24 Gbps of data. The rest of the 40 Gbps can be used by DisplayPort if a display is connected.
USB 3.1 gen 1 (or USB 3.0) is 5 Gbps which should allow up to 450 MB/s. USB 3.1 gen 2 is 10 Gbps which should allow up to 1000 MB/s.

Will anything change if I bought a thunderbolt USB-C to USB-C cable? And who are these crazy speeds for? As far as research I seen, even T7 does roughly 700/900 read-write. It's not that I need 40GBs, I'm trying to understand what would that speed be for, and it just feels that there is more marketing in it than actual necessity.
If you're using an M1 Mac, then that's a problem. The M1 Macs have slower than normal USB speeds with its built-in USB controller. The workaround is to use an external USB controller which you can get with a Thunderbolt dock (or any Thunderbolt device with a USB port or a second Thunderbolt 3 port).
 

chabig

macrumors G4
Sep 6, 2002
11,456
9,324
It's not that I need 40GBs, I'm trying to understand what would that speed be for,...
Remember too, that these are busses. So don't limit yourself to thinking that only two devices are connected. The total bandwidth of the bus is shared by all devices, so you could theoretically run four of you Netac devices on a Thunderbolt 2 bus and none of the data transfers would be bottlenecked.
 

Boyd01

Moderator
Staff member
Feb 21, 2012
7,952
4,888
New Jersey Pine Barrens
So, with the T7, it would be 10,000Mbps / 10 = about 1,000MBps maximum speed, which is close to the 900MBps read speeds that people are reporting.

I can confirm that. :)

samsung-t7-2tb.png
 
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TrancyGoose

macrumors 6502
Original poster
Jan 13, 2021
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What is it that you do with your drive?

My main use would be storing Logic Pro Library files, and music. I do not do video editing or large photos. I am actually considering keeping the SSD for docs and family pics and getting a 4TB HDD for Logic Library and projects.


400MB/s is kind of low. There might be a problem where the USB device is connecting only at USB 3.0 speed (5 Gbps). Check System Information.app. Make sure the device is connecting at Up to 10 Gbps speed.

So here is the system info I pulled off the hub. For some reason, hub shows as 3.0 but the speed is up to 10 GB/s so appears correct, I used a different cheaper hub before, this is why maybe the report is confused. Or I am confused lol.

Screenshot 2021-04-07 at 22.19.59.png

If you're using an M1 Mac, then that's a problem. The M1 Macs have slower than normal USB speeds with its built-in USB controller. The workaround is to use an external USB controller which you can get with a Thunderbolt dock (or any Thunderbolt device with a USB port or a second Thunderbolt 3 port).

Thank you for your very detailed answer, really. But I don't think with my use, I really need to spend more cash! :)

Also thanks to everyone for the very detailed answers. What I realized is, that for a guy like me, I don't need so much speed. I threw a 1GB file on the drive and it took seconds for it to land there. Wish they didn't make the USB classifications so damn complicated to understand. Won't be buying a T7 either. I'll stick with what I have for now for my use and add a reliable 4TB HDD storage.

Been eyeing these two:



Toshiba one has USB 3.2 gen 2 and is cheaper than Lacie, so I'll probably get that. Although, Lacie does look better but with USB 3.0.

Huge thanks for you effort folks, did not expect such detailed responses.
 

joevt

macrumors 604
Jun 21, 2012
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Remember too, that these are busses. So don't limit yourself to thinking that only two devices are connected. The total bandwidth of the bus is shared by all devices, so you could theoretically run four of you Netac devices on a Thunderbolt 2 bus and none of the data transfers would be bottlenecked.
Each Netac would need to be connected to a different USB controller (or at least no more than two per 10 Gbps USB controller). The CalDigit TS3+ Thunderbolt Dock has 4 separate USB controllers (two 5 Gbps and two 10 Gbps - sort of). The CalDigit Element Hub and other Thunderbolt 4 hubs/docks have only one 10 Gbps USB controller.

So here is the system info I pulled off the hub. For some reason, hub shows as 3.0 but the speed is up to 10 GB/s so appears correct, I used a different cheaper hub before, this is why maybe the report is confused. Or I am confused lol.
You mean 10 Gb/s. b=bit. B=Byte. You need to check the parents to make sure they're all 10 Gbps. Click the parent bus to show the info for the bus and the hub and the device. You can use a low resolution mode (not HiDPI) to make screenshots that show more info.

Thank you for your very detailed answer, really. But I don't think with my use, I really need to spend more cash! :)
You didn't say what kind of Mac you have.

Been eyeing these two:

Toshiba one has USB 3.2 gen 2 and is cheaper than Lacie, so I'll probably get that. Although, Lacie does look better but with USB 3.0.

Huge thanks for you effort folks, did not expect such detailed responses.
They both are using spinning disks, so they'll both be limited to 120 MB/s or whatever. USB 3.1 gen 2 won't help much here.
 
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padams35

macrumors 6502a
Nov 10, 2016
502
348
Its worth mention that Thunderbolt bandwidth is for data+video. The data-only limits are lower.

Thunderbolt-1: Up to 10Gbps data + up to 10Gbps video out.

Thunderbolt-2: 20Gbps max combined data+video out.
Data only: 16Gbps max. (PCIe 2.0x4)
Video only: 17Gbps max. (DisplayPort 1.2)

Thunderbolt-3: 40Gbps max combined data+video out.
Data only: 22Gbps max. (PCIe 3.0x4 (32Gbps) shared between two ports, with 10Gbps minimum reserved/guaranteed to each port to match USB-C 3.2 Gen 2).
Video only: 34Gbps max. (2x DisplayPort 1.2 channels shared between two ports).


Also the OP's Netac (Slim) sounds like it is a SATA type SSD. SATA based devices max out at 6Gbps even with a faster cables.
 
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TrancyGoose

macrumors 6502
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Jan 13, 2021
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You didn't say what kind of Mac you have.
I own a A2338 M1 Macbook Pro, great machine, loving it

You mean 10 Gb/s. b=bit. B=Byte. You need to check the parents to make sure they're all 10 Gbps. Click the parent bus to show the info for the bus and the hub and the device. You can use a low resolution mode (not HiDPI) to make screenshots that show more info.

So here is what I got, it is gibberish to me, I haven't used a Mac in a while, and I am not that advanced in deep technical stuff, though, it seems some stuff there is 5GB's, and hub shows up as USB 3.1 but then splits to USB 3.0
Either way, I feel a bit cheated now by the manufacturer. Or maybe I am doing it wrong, but it will do for my user of storing DAW libraries and working on projects there. Screenshot 2021-04-08 at 21.37.36.png Screenshot 2021-04-08 at 21.37.50.png Screenshot 2021-04-08 at 21.38.03.png Screenshot 2021-04-08 at 21.38.19.png Screenshot 2021-04-08 at 21.38.35.png Screenshot 2021-04-07 at 22.19.59.png
 

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Juicy Box

macrumors 604
Sep 23, 2014
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That hub has USB3.0 5Gbps USB-C ports. Try plugging your SSD directly to your Mac and check the speed.
I just reviewed the thread again and saw this:
I tested the SSD I have with the stock cable it came with, via the HUB and plugged directly in to the thunderbolt port with USB C adapter on it. And I am still only getting roughly 400MB read/write on BlackMagic.

You can try another cable, but considering that is most likely a SATAIII SSD, you probably will not get much better than 400MBps, even if that cable provide with the hub was only USB3 5Gbps.
 

TrancyGoose

macrumors 6502
Original poster
Jan 13, 2021
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That hub has USB3.0 5Gbps USB-C ports. Try plugging your SSD directly to your Mac and check the speed.
nope, getting the same speeds! :) I guess SSD matters, thank you all for support, I have grown much smarter now.
For my use, this will be enough, no need to spend money on a T7. Thanks a lot. Screenshot 2021-04-08 at 23.37.18.png

This is plugged in, directly in to the thunderbolt port.
 
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TrancyGoose

macrumors 6502
Original poster
Jan 13, 2021
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They both are using spinning disks, so they'll both be limited to 120 MB/s or whatever. USB 3.1 gen 2 won't help much here.
Tell me, is it ok to use a spinning drive for storage? :))) Or would it be wrong to buy it? Is there anything wrong with a spinning drive? I can get 4TB for a lot less money :D
 

HDFan

Contributor
Jun 30, 2007
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Tell me, is it ok to use a spinning drive for storage? :))) Or would it be wrong to buy it? Is there anything wrong with a spinning drive? I can get 4TB for a lot less money

A spinning drive is generally best for storage, due to cost effectiveness and (sometimes) longevity. SSDs aren't yet the generic solution. They are best in certain circumstances - boot drive, poor environmental conditions, or extremely fast random access required.
 

joevt

macrumors 604
Jun 21, 2012
6,968
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That hub has USB3.0 5Gbps USB-C ports. Try plugging your SSD directly to your Mac and check the speed.
No. Look at the Anker USB C Hub, PowerExpand 8-in-1 USB C Adapter images at https://www.amazon.co.uk/gp/product/B087QZVQJX
Notice that it has 3 USB 3.1 gen 2 ports, an SD card reader, and an Ethernet port. That's 5 devices. USB 3.1 gen 2 hubs usually only have 4 ports, so the Anker includes a USB 3.0 hub for the slower devices. It's like this:

Code:
    - USB 3.1 gen 2 hub
        - USB-C
        - USB-A
        - USB-A
        - USB 3.0 hub
            - Alcorlink USB 3.0 Card Reader
            - Realtek Gigabit Ethernet
        - USB 2.0 Billboard device
I own a A2338 M1 Macbook Pro, great machine, loving it
M1 Macs are known for USB problems - slower than normal speeds for both 5 Gbps and 10 Gbps devices, and sometimes a 10 Gbps device may connect at 5 Gbps.

So here is what I got, it is gibberish to me, I haven't used a Mac in a while, and I am not that advanced in deep technical stuff, though, it seems some stuff there is 5GB's, and hub shows up as USB 3.1 but then splits to USB 3.0
Either way, I feel a bit cheated now by the manufacturer. Or maybe I am doing it wrong, but it will do for my user of storing DAW libraries and working on projects there.

I rearranged the info:
Code:
- USB 3.1 Bus: AppleT8103USBXHCI (crappy Apple M1 USB controller)
    - 10 Gbps 4-Port USB 3.0 Hub (Anker)                                - 4-Port USB 2.0 Hub (Anker)
        - 10 Gbps Netac MobileDataStar                                      -
        - 5 Gbps USB 3.1 Hub (Gensys Logic, Inc.)                           - USB 2.1 Hub (Gensys Logic, Inc.)
            - 5 Gbps Mass Storage Device (Alco Micro, Corp.)                    -      
            - 5 Gbps USB 10/100/1000 LAN (Realtek Semiconductor Corp.)          -        
        -                                                                   - Billboard Device (Realtek Semiconductor Corp.)
A USB bus or hub has a USB 2.x port for each USB 3.x port. The USB 2.0 and USB 3.x topologies are otherwise completely separate (they don't use the same wires). You can think of the USB 2.0 tree as being parallel to the USB 3.x tree (which is how I arranged it above). A USB-C hub or adapter usually includes a billboard device on the USB 2.0 tree.

Everything appears to be connected correctly - the base of the tree is 10 Gbps. It changes to 5 Gbps at the USB 3.0 hub for the SD Card Reader and the Ethernet port.

An easier, more readable or at least easier to work with, method to get the info from System Information.app is to use this command:
system_profiler SPUSBDataType

One problem with this info from System Information.app is that it doesn't show unused ports. This command will show unused ports and shows where the USB controller is:
ioreg -itrc AppleUSBHostController

Tell me, is it ok to use a spinning drive for storage? :))) Or would it be wrong to buy it? Is there anything wrong with a spinning drive? I can get 4TB for a lot less money :D
Spinning drives are fine. Just don't drop them too much.
 

Juicy Box

macrumors 604
Sep 23, 2014
7,580
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No. Look at the Anker USB C Hub, PowerExpand 8-in-1 USB C Adapter images at https://www.amazon.co.uk/gp/product/B087QZVQJX
Notice that it has 3 USB 3.1 gen 2 ports, an SD card reader, and an Ethernet port. That's 5 devices. USB 3.1 gen 2 hubs usually only have 4 ports, so the Anker includes a USB 3.0 hub for the slower devices. It's like this:

Code:
- USB 3.1 gen 2 hub
- USB-C
- USB-A
- USB-A
- USB 3.0 hub
- Alcorlink USB 3.0 Card Reader
- Realtek Gigabit Ethernet
- USB 2.0 Billboard device
I did look at the images right from the link, and there are inconsistencies, look:

USB3 1.png


and in the description:

USB3 2.png


Maybe I am looking at it wrong...
 

joevt

macrumors 604
Jun 21, 2012
6,968
4,262
I did look at the images right from the link, and there are inconsistencies, look:

View attachment 1755549

and in the description:

View attachment 1755548

Maybe I am looking at it wrong...
You're right. They are very inconsistent. The image you show is only at https://www.amazon.com/dp/B087QZVQJX
It is not in the original link at https://www.amazon.co.uk/gp/product/B087QZVQJX
but both sites mention USB 3.0.

I like this picture where it clearly shows that the speed of each USB port is marked on the product itself as 10 Gb/s:
but they ruin it with some made up numbers 10240 Mbps and 5120 Mbps. They multiplied 5 and 10 by 1024 - as if Mbps (Megabits/s) is supposed to be Mibps (Mebibits/s).
https://en.wikipedia.org/wiki/Gibibit https://en.wikipedia.org/wiki/Mebibit

USB 3.1 gen 2 transmits 10 Gbps (1000000000 bits) not 10240 Mb and not 10240 Mib. It uses 128b/132b encoding which means it takes 132 bits on the wire to transmit 128 bits so the actual data rate is 9.697 Gbps. USB 3.0 transmits 5 Gbps (5000000000 bits) using 8b/10b encoding, so the amount of data is 4 Gb/s.
 
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TrancyGoose

macrumors 6502
Original poster
Jan 13, 2021
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You're right. They are very inconsistent. The image you show is only at https://www.amazon.com/dp/B087QZVQJX
It is not in the original link at https://www.amazon.co.uk/gp/product/B087QZVQJX
but both sites mention USB 3.0.

I like this picture where it clearly shows that the speed of each USB port is marked on the product itself as 10 Gb/s:
but they ruin it with some made up numbers 10240 Mbps and 5120 Mbps. They multiplied 5 and 10 by 1024 - as if Mbps (Megabits/s) is supposed to be Mibps (Mebibits/s).
https://en.wikipedia.org/wiki/Gibibit https://en.wikipedia.org/wiki/Mebibit

USB 3.1 gen 2 transmits 10 Gbps (1000000000 bits) not 10240 Mb and not 10240 Mib. It uses 128b/132b encoding which means it takes 132 bits on the wire to transmit 128 bits so the actual data rate is 9.697 Gbps. USB 3.0 transmits 5 Gbps (5000000000 bits) using 8b/10b encoding, so the amount of data is 4 Gb/s.
Just happy to report that hub mentioned above has successfully died, and HDMI stopped working. Took a cheap spare hub, works, so that hub no good.

I also realised that for my needs, I no need to worry about 3.0 or 3.1, 3.0 is more than enough to run a small ssd i have and a spinning drive from Lacie.

Thanks all
 
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