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Manulobo22
Posts: 21
Joined: Sat Oct 05, 2019 9:28 pm

Worse USB speed on RPI 4 than RPI 3 B

Wed Nov 13, 2019 12:39 pm

Hello, i have a big problem here... I have an USB camera, and i tested the speed in my old RPI 3 model B, and i get ~20MB/s. When i tested on my RPI 4 model B, the speed was ~15MB/s.. What is happening ? Power supply are the same in both (5.25V 3A). And both have the SAME system and software.

I tried using Raspbian Buster, Ubuntu server 19.10 and DietPi.

Any help with these ? Thank you
Last edited by Manulobo22 on Wed Nov 13, 2019 2:03 pm, edited 1 time in total.
wildfire
Posts: 606
Joined: Sat Sep 03, 2016 10:39 am
Location: Dundee, Scotland

Re: Worse USB speed on RPI 4 than RPI 3 B

Wed Nov 13, 2019 1:30 pm

Manulobo22 wrote: ↑
Wed Nov 13, 2019 12:39 pm
 I tried using Raspbian Buster, Raspbian Strech, Ubuntu server 19.10 and DietPi.
No help I'm afraid but curious. How did you manage to get strech <sic> running on a 4b?
E8 85 A2 64 C9 64 81 94 64 81 95 64 89 84 89 96 A3
Still NF Shirls
Manulobo22
Posts: 21
Joined: Sat Oct 05, 2019 9:28 pm

Re: Worse USB speed on RPI 4 than RPI 3 B

Wed Nov 13, 2019 2:04 pm

wildfire wrote: ↑
Wed Nov 13, 2019 1:30 pm
Manulobo22 wrote: ↑
Wed Nov 13, 2019 12:39 pm
 I tried using Raspbian Buster, Raspbian Strech, Ubuntu server 19.10 and DietPi.
No help I'm afraid but curious. How did you manage to get strech <sic> running on a 4b?
No, sorry. Only in Buster, i edited the post
Brad Q
Posts: 95
Joined: Mon Aug 12, 2019 12:10 am

Re: Worse USB speed on RPI 4 than RPI 3 B

Thu Nov 14, 2019 10:16 pm

Not sure if it would make a difference but are you using the 2.0 us ports on the Pi4 or the 3.0 ports?
Manulobo22
Posts: 21
Joined: Sat Oct 05, 2019 9:28 pm

Re: Worse USB speed on RPI 4 than RPI 3 B

Fri Nov 15, 2019 2:16 am

Brad Q wrote: ↑
Thu Nov 14, 2019 10:16 pm
 Not sure if it would make a difference but are you using the 2.0 us ports on the Pi4 or the 3.0 ports?
Hello, i tested in both and were the same
Brad Q
Posts: 95
Joined: Mon Aug 12, 2019 12:10 am

Re: Worse USB speed on RPI 4 than RPI 3 B

Fri Nov 15, 2019 3:18 am

You might try a lsusb and look and see if there is a compatibility issue with that device.
Manulobo22
Posts: 21
Joined: Sat Oct 05, 2019 9:28 pm

Re: Worse USB speed on RPI 4 than RPI 3 B

Fri Nov 15, 2019 3:24 am

Brad Q wrote: ↑
Fri Nov 15, 2019 3:18 am
 You might try a lsusb and look and see if there is a compatibility issue with that device.
Here is my lsusb:

Code: Select all

Bus 003 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 002 Device 002: ID 2357:0115 TP-Link 802.11ac NIC
Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
[b]Bus 001 Device 007: ID 045e:02ae Microsoft Corp. Xbox NUI Camera
Bus 001 Device 006: ID 045e:02ad Microsoft Corp. Xbox NUI Audio
Bus 001 Device 004: ID 045e:02c2 Microsoft Corp. Kinect for Windows NUI Motor[/b]
Bus 001 Device 002: ID 2109:3431 VIA Labs, Inc. Hub
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub


Here is my lshw:

Code: Select all

/:  Bus 03.Port 1: Dev 1, Class=root_hub, Driver=dwc_otg/1p, 480M
/:  Bus 02.Port 1: Dev 1, Class=root_hub, Driver=xhci_hcd/4p, 5000M
    |__ Port 1: Dev 2, If 0, Class=Vendor Specific Class, Driver=rtl88x2bu, 5000M
/:  Bus 01.Port 1: Dev 1, Class=root_hub, Driver=xhci_hcd/1p, 480M
    |__ Port 1: Dev 2, If 0, Class=Hub, Driver=hub/4p, 480M
        |__ Port 4: Dev 4, If 0, Class=Hub, Driver=hub/2p, 480M
            |__ Port 1: Dev 6, If 0, Class=Vendor Specific Class, Driver=, 480M
            |__ Port 2: Dev 7, If 0, Class=Vendor Specific Class, Driver=kinect, 480M

And here my lsusb -v

Code: Select all

Bus 003 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Couldn't open device, some information will be missing
Device Descriptor:
  bLength                18
  bDescriptorType         1
  bcdUSB               2.00
  bDeviceClass            9 Hub
  bDeviceSubClass         0 
  bDeviceProtocol         1 Single TT
  bMaxPacketSize0        64
  idVendor           0x1d6b Linux Foundation
  idProduct          0x0002 2.0 root hub
  bcdDevice            5.03
  iManufacturer           3 
  iProduct                2 
  iSerial                 1 
  bNumConfigurations      1
  Configuration Descriptor:
    bLength                 9
    bDescriptorType         2
    wTotalLength       0x0019
    bNumInterfaces          1
    bConfigurationValue     1
    iConfiguration          0 
    bmAttributes         0xe0
      Self Powered
      Remote Wakeup
    MaxPower                0mA
    Interface Descriptor:
      bLength                 9
      bDescriptorType         4
      bInterfaceNumber        0
      bAlternateSetting       0
      bNumEndpoints           1
      bInterfaceClass         9 Hub
      bInterfaceSubClass      0 
      bInterfaceProtocol      0 Full speed (or root) hub
      iInterface              0 
      Endpoint Descriptor:
        bLength                 7
        bDescriptorType         5
        bEndpointAddress     0x81  EP 1 IN
        bmAttributes            3
          Transfer Type            Interrupt
          Synch Type               None
          Usage Type               Data
        wMaxPacketSize     0x0004  1x 4 bytes
        bInterval              12

Bus 002 Device 002: ID 2357:0115 TP-Link 802.11ac NIC
Couldn't open device, some information will be missing
Device Descriptor:
  bLength                18
  bDescriptorType         1
  bcdUSB               3.00
  bDeviceClass            0 
  bDeviceSubClass         0 
  bDeviceProtocol         0 
  bMaxPacketSize0         9
  idVendor           0x2357 TP-Link
  idProduct          0x0115 
  bcdDevice            3.00
  iManufacturer           1 
  iProduct                2 
  iSerial                 3 
  bNumConfigurations      1
  Configuration Descriptor:
    bLength                 9
    bDescriptorType         2
    wTotalLength       0x0053
    bNumInterfaces          1
    bConfigurationValue     1
    iConfiguration          0 
    bmAttributes         0x80
      (Bus Powered)
    MaxPower              504mA
    Interface Descriptor:
      bLength                 9
      bDescriptorType         4
      bInterfaceNumber        0
      bAlternateSetting       0
      bNumEndpoints           5
      bInterfaceClass       255 Vendor Specific Class
      bInterfaceSubClass    255 Vendor Specific Subclass
      bInterfaceProtocol    255 Vendor Specific Protocol
      iInterface              2 
      Endpoint Descriptor:
        bLength                 7
        bDescriptorType         5
        bEndpointAddress     0x84  EP 4 IN
        bmAttributes            2
          Transfer Type            Bulk
          Synch Type               None
          Usage Type               Data
        wMaxPacketSize     0x0400  1x 1024 bytes
        bInterval               0
        bMaxBurst               3
      Endpoint Descriptor:
        bLength                 7
        bDescriptorType         5
        bEndpointAddress     0x05  EP 5 OUT
        bmAttributes            2
          Transfer Type            Bulk
          Synch Type               None
          Usage Type               Data
        wMaxPacketSize     0x0400  1x 1024 bytes
        bInterval               0
        bMaxBurst               3
      Endpoint Descriptor:
        bLength                 7
        bDescriptorType         5
        bEndpointAddress     0x06  EP 6 OUT
        bmAttributes            2
          Transfer Type            Bulk
          Synch Type               None
          Usage Type               Data
        wMaxPacketSize     0x0400  1x 1024 bytes
        bInterval               0
        bMaxBurst               3
      Endpoint Descriptor:
        bLength                 7
        bDescriptorType         5
        bEndpointAddress     0x87  EP 7 IN
        bmAttributes            3
          Transfer Type            Interrupt
          Synch Type               None
          Usage Type               Data
        wMaxPacketSize     0x0040  1x 64 bytes
        bInterval               3
        bMaxBurst               0
      Endpoint Descriptor:
        bLength                 7
        bDescriptorType         5
        bEndpointAddress     0x08  EP 8 OUT
        bmAttributes            2
          Transfer Type            Bulk
          Synch Type               None
          Usage Type               Data
        wMaxPacketSize     0x0400  1x 1024 bytes
        bInterval               0
        bMaxBurst               3

Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Couldn't open device, some information will be missing
Device Descriptor:
  bLength                18
  bDescriptorType         1
  bcdUSB               3.00
  bDeviceClass            9 Hub
  bDeviceSubClass         0 
  bDeviceProtocol         3 
  bMaxPacketSize0         9
  idVendor           0x1d6b Linux Foundation
  idProduct          0x0003 3.0 root hub
  bcdDevice            5.03
  iManufacturer           3 
  iProduct                2 
  iSerial                 1 
  bNumConfigurations      1
  Configuration Descriptor:
    bLength                 9
    bDescriptorType         2
    wTotalLength       0x001f
    bNumInterfaces          1
    bConfigurationValue     1
    iConfiguration          0 
    bmAttributes         0xe0
      Self Powered
      Remote Wakeup
    MaxPower                0mA
    Interface Descriptor:
      bLength                 9
      bDescriptorType         4
      bInterfaceNumber        0
      bAlternateSetting       0
      bNumEndpoints           1
      bInterfaceClass         9 Hub
      bInterfaceSubClass      0 
      bInterfaceProtocol      0 Full speed (or root) hub
      iInterface              0 
      Endpoint Descriptor:
        bLength                 7
        bDescriptorType         5
        bEndpointAddress     0x81  EP 1 IN
        bmAttributes            3
          Transfer Type            Interrupt
          Synch Type               None
          Usage Type               Data
        wMaxPacketSize     0x0004  1x 4 bytes
        bInterval              12
        bMaxBurst               0

Bus 001 Device 007: ID 045e:02ae Microsoft Corp. Xbox NUI Camera
Device Descriptor:
  bLength                18
  bDescriptorType         1
  bcdUSB               2.00
  bDeviceClass            0 
  bDeviceSubClass         0 
  bDeviceProtocol         0 
  bMaxPacketSize0        64
  idVendor           0x045e Microsoft Corp.
  idProduct          0x02ae Xbox NUI Camera
  bcdDevice            2.05
  iManufacturer           2 Microsoft
  iProduct                1 Xbox NUI Camera
  iSerial                 3 0000000000000000
  bNumConfigurations      1
  Configuration Descriptor:
    bLength                 9
    bDescriptorType         2
    wTotalLength       0x0020
    bNumInterfaces          1
    bConfigurationValue     1
    iConfiguration          0 
    bmAttributes         0xc0
      Self Powered
    MaxPower               16mA
    Interface Descriptor:
      bLength                 9
      bDescriptorType         4
      bInterfaceNumber        0
      bAlternateSetting       0
      bNumEndpoints           2
      bInterfaceClass       255 Vendor Specific Class
      bInterfaceSubClass      0 
      bInterfaceProtocol    255 
      iInterface              0 
      Endpoint Descriptor:
        bLength                 7
        bDescriptorType         5
        bEndpointAddress     0x81  EP 1 IN
        bmAttributes            1
          Transfer Type            Isochronous
          Synch Type               None
          Usage Type               Data
        wMaxPacketSize     0x0bc0  2x 960 bytes
        bInterval               1
      Endpoint Descriptor:
        bLength                 7
        bDescriptorType         5
        bEndpointAddress     0x82  EP 2 IN
        bmAttributes            1
          Transfer Type            Isochronous
          Synch Type               None
          Usage Type               Data
        wMaxPacketSize     0x0bc0  2x 960 bytes
        bInterval               1
Device Qualifier (for other device speed):
  bLength                10
  bDescriptorType         6
  bcdUSB               2.00
  bDeviceClass            0 
  bDeviceSubClass         0 
  bDeviceProtocol         0 
  bMaxPacketSize0        64
  bNumConfigurations      1
can't get debug descriptor: Resource temporarily unavailable
Device Status:     0x0001
  Self Powered

Bus 001 Device 006: ID 045e:02ad Microsoft Corp. Xbox NUI Audio
Device Descriptor:
  bLength                18
  bDescriptorType         1
  bcdUSB               2.00
  bDeviceClass          255 Vendor Specific Class
  bDeviceSubClass         0 
  bDeviceProtocol         0 
  bMaxPacketSize0        64
  idVendor           0x045e Microsoft Corp.
  idProduct          0x02ad Xbox NUI Audio
  bcdDevice            1.00
  iManufacturer           1 Microsoft
  iProduct                2 Xbox Kinect Audio, © 2011 Microsoft Corporation. All rights reserved.
  iSerial                 3 A70776X02020240A
  bNumConfigurations      1
  Configuration Descriptor:
    bLength                 9
    bDescriptorType         2
    wTotalLength       0x002e
    bNumInterfaces          1
    bConfigurationValue     1
    iConfiguration          0 
    bmAttributes         0xc0
      Self Powered
    MaxPower                0mA
    Interface Descriptor:
      bLength                 9
      bDescriptorType         4
      bInterfaceNumber        0
      bAlternateSetting       0
      bNumEndpoints           4
      bInterfaceClass       255 Vendor Specific Class
      bInterfaceSubClass      0 
      bInterfaceProtocol      0 
      iInterface              4 Config
      Endpoint Descriptor:
        bLength                 7
        bDescriptorType         5
        bEndpointAddress     0x81  EP 1 IN
        bmAttributes            2
          Transfer Type            Bulk
          Synch Type               None
          Usage Type               Data
        wMaxPacketSize     0x0200  1x 512 bytes
        bInterval               1
      Endpoint Descriptor:
        bLength                 7
        bDescriptorType         5
        bEndpointAddress     0x01  EP 1 OUT
        bmAttributes            2
          Transfer Type            Bulk
          Synch Type               None
          Usage Type               Data
        wMaxPacketSize     0x0200  1x 512 bytes
        bInterval               1
      Endpoint Descriptor:
        bLength                 7
        bDescriptorType         5
        bEndpointAddress     0x82  EP 2 IN
        bmAttributes           13
          Transfer Type            Isochronous
          Synch Type               Synchronous
          Usage Type               Data
        wMaxPacketSize     0x020c  1x 524 bytes
        bInterval               5
      Endpoint Descriptor:
        bLength                 7
        bDescriptorType         5
        bEndpointAddress     0x02  EP 2 OUT
        bmAttributes           13
          Transfer Type            Isochronous
          Synch Type               Synchronous
          Usage Type               Data
        wMaxPacketSize     0x004c  1x 76 bytes
        bInterval               1
Device Qualifier (for other device speed):
  bLength                10
  bDescriptorType         6
  bcdUSB               2.00
  bDeviceClass          255 Vendor Specific Class
  bDeviceSubClass         0 
  bDeviceProtocol         0 
  bMaxPacketSize0        64
  bNumConfigurations      1
can't get debug descriptor: Resource temporarily unavailable
Device Status:     0x0001
  Self Powered

Bus 001 Device 004: ID 045e:02c2 Microsoft Corp. Kinect for Windows NUI Motor
Couldn't open device, some information will be missing
Device Descriptor:
  bLength                18
  bDescriptorType         1
  bcdUSB               2.00
  bDeviceClass            9 Hub
  bDeviceSubClass         0 
  bDeviceProtocol         1 Single TT
  bMaxPacketSize0        64
  idVendor           0x045e Microsoft Corp.
  idProduct          0x02c2 Kinect for Windows NUI Motor
  bcdDevice            0.01
  iManufacturer           0 
  iProduct                0 
  iSerial                 0 
  bNumConfigurations      1
  Configuration Descriptor:
    bLength                 9
    bDescriptorType         2
    wTotalLength       0x0019
    bNumInterfaces          1
    bConfigurationValue     1
    iConfiguration          0 
    bmAttributes         0xe0
      Self Powered
      Remote Wakeup
    MaxPower                2mA
    Interface Descriptor:
      bLength                 9
      bDescriptorType         4
      bInterfaceNumber        0
      bAlternateSetting       0
      bNumEndpoints           1
      bInterfaceClass         9 Hub
      bInterfaceSubClass      0 
      bInterfaceProtocol      0 Full speed (or root) hub
      iInterface              0 
      Endpoint Descriptor:
        bLength                 7
        bDescriptorType         5
        bEndpointAddress     0x81  EP 1 IN
        bmAttributes            3
          Transfer Type            Interrupt
          Synch Type               None
          Usage Type               Data
        wMaxPacketSize     0x0001  1x 1 bytes
        bInterval              12

Bus 001 Device 002: ID 2109:3431 VIA Labs, Inc. Hub
Couldn't open device, some information will be missing
Device Descriptor:
  bLength                18
  bDescriptorType         1
  bcdUSB               2.10
  bDeviceClass            9 Hub
  bDeviceSubClass         0 
  bDeviceProtocol         1 Single TT
  bMaxPacketSize0        64
  idVendor           0x2109 VIA Labs, Inc.
  idProduct          0x3431 Hub
  bcdDevice            4.20
  iManufacturer           0 
  iProduct                1 
  iSerial                 0 
  bNumConfigurations      1
  Configuration Descriptor:
    bLength                 9
    bDescriptorType         2
    wTotalLength       0x0019
    bNumInterfaces          1
    bConfigurationValue     1
    iConfiguration          0 
    bmAttributes         0xe0
      Self Powered
      Remote Wakeup
    MaxPower              100mA
    Interface Descriptor:
      bLength                 9
      bDescriptorType         4
      bInterfaceNumber        0
      bAlternateSetting       0
      bNumEndpoints           1
      bInterfaceClass         9 Hub
      bInterfaceSubClass      0 
      bInterfaceProtocol      0 Full speed (or root) hub
      iInterface              0 
      Endpoint Descriptor:
        bLength                 7
        bDescriptorType         5
        bEndpointAddress     0x81  EP 1 IN
        bmAttributes            3
          Transfer Type            Interrupt
          Synch Type               None
          Usage Type               Data
        wMaxPacketSize     0x0001  1x 1 bytes
        bInterval              12

Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Couldn't open device, some information will be missing
Device Descriptor:
  bLength                18
  bDescriptorType         1
  bcdUSB               2.00
  bDeviceClass            9 Hub
  bDeviceSubClass         0 
  bDeviceProtocol         1 Single TT
  bMaxPacketSize0        64
  idVendor           0x1d6b Linux Foundation
  idProduct          0x0002 2.0 root hub
  bcdDevice            5.03
  iManufacturer           3 
  iProduct                2 
  iSerial                 1 
  bNumConfigurations      1
  Configuration Descriptor:
    bLength                 9
    bDescriptorType         2
    wTotalLength       0x0019
    bNumInterfaces          1
    bConfigurationValue     1
    iConfiguration          0 
    bmAttributes         0xe0
      Self Powered
      Remote Wakeup
    MaxPower                0mA
    Interface Descriptor:
      bLength                 9
      bDescriptorType         4
      bInterfaceNumber        0
      bAlternateSetting       0
      bNumEndpoints           1
      bInterfaceClass         9 Hub
      bInterfaceSubClass      0 
      bInterfaceProtocol      0 Full speed (or root) hub
      iInterface              0 
      Endpoint Descriptor:
        bLength                 7
        bDescriptorType         5
        bEndpointAddress     0x81  EP 1 IN
        bmAttributes            3
          Transfer Type            Interrupt
          Synch Type               None
          Usage Type               Data
        wMaxPacketSize     0x0004  1x 4 bytes
        bInterval              12
Thank you
Brad Q
Posts: 95
Joined: Mon Aug 12, 2019 12:10 am

Re: Worse USB speed on RPI 4 than RPI 3 B

Fri Nov 15, 2019 3:37 am

First, that is a LOT of devices to be running off the Pi all at once. There are a couple of potential problems there, power and bandwidth. IF I remember correctly the USB total bandwidth for the Pi4 is 350MBps(MB not Mb), so you could be running into an issue there. Second the power draw of the Pi4 itself is quite a bit higher than the Pi3 series, so you cold be running into power issues. Try removing as much stuff off the USB as possible and rerun your tests. IF it does make a difference you might look at a powered USB hub to drop the load off of the Pi. IF it is a bandwidth issue, you may need to look at other options (split the project into two separate Pis?). It could also still be that there is some sort of conflict issue between the Pi4 and your camera or between your camera and one of the other devices.
Manulobo22
Posts: 21
Joined: Sat Oct 05, 2019 9:28 pm

Re: Worse USB speed on RPI 4 than RPI 3 B

Fri Nov 15, 2019 3:45 am

Brad Q wrote: ↑
Fri Nov 15, 2019 3:37 am
 First, that is a LOT of devices to be running off the Pi all at once. There are a couple of potential problems there, power and bandwidth. IF I remember correctly the USB total bandwidth for the Pi4 is 350MBps(MB not Mb), so you could be running into an issue there. Second the power draw of the Pi4 itself is quite a bit higher than the Pi3 series, so you cold be running into power issues. Try removing as much stuff off the USB as possible and rerun your tests. IF it does make a difference you might look at a powered USB hub to drop the load off of the Pi. IF it is a bandwidth issue, you may need to look at other options (split the project into two separate Pis?). It could also still be that there is some sort of conflict issue between the Pi4 and your camera or between your camera and one of the other devices.
Currently I only have the kinect and a TPLINK wifi connected. When the kinect is connected, lsusb shows three different devices, but it's only one.

I tried using an USB-Y cable, so i powered the USB with an external adapter supply, but it didn't have any improve.

Why did you say 350MBps at maximum ? I believed that RPI4 had a lot of more bandwidth, because of the USB 3.0.. So if the total bandwidth is 350MBps, why the RPI4 has USB 3.0 ?

Although 350MB is a lot for me, but only i could get 15MB/s in my RPI4 and 20MB/s in my RPI3.

Thank you !
Brad Q
Posts: 95
Joined: Mon Aug 12, 2019 12:10 am

Re: Worse USB speed on RPI 4 than RPI 3 B

Fri Nov 15, 2019 4:22 am

First just to make sure: you understand that MBps is Megabytes per second and Mbps is Megabits per second? For instance gigabit Ethernet is 1000Mbps but only 125MBps(theoretically).

The limitation came about in discussing the SD card reader vs a USB device (40MBps vs 350MBps). I took a quick look around and could not find any documentation to actually back either statement up. But that could just be my Google Fu failing on me.

I am not sure about using a Y cable on USB. As wifi stuff are known to be the biggest common power hogs I would try without it. What speed is the camera supposed to be capable of?
Manulobo22
Posts: 21
Joined: Sat Oct 05, 2019 9:28 pm

Re: Worse USB speed on RPI 4 than RPI 3 B

Fri Nov 15, 2019 10:12 am

Brad Q wrote: ↑
Fri Nov 15, 2019 4:22 am
 First just to make sure: you understand that MBps is Megabytes per second and Mbps is Megabits per second? For instance gigabit Ethernet is 1000Mbps but only 125MBps(theoretically).

The limitation came about in discussing the SD card reader vs a USB device (40MBps vs 350MBps). I took a quick look around and could not find any documentation to actually back either statement up. But that could just be my Google Fu failing on me.

I am not sure about using a Y cable on USB. As wifi stuff are known to be the biggest common power hogs I would try without it. What speed is the camera supposed to be capable of?
Yes, the camera in my PC runs at 26
Megabytes/s. I tried in the RPIs without wifi but i got the same results.

What i don't understand is why in the RPI3 i get 20 Megabytes/s and in the RPI4 15 Megabytes/s, usign the same power supply.

I have an originam Sandik ultra 16gb up to 80MB/s.

Just for adding information, when i'am using the wifi TPlink T4U (USB 3.0), and i test iperf3 -c IP -f M, i get 60 Megabytes/s, so the wifi works correctly.
Brad Q
Posts: 95
Joined: Mon Aug 12, 2019 12:10 am

Re: Worse USB speed on RPI 4 than RPI 3 B

Fri Nov 15, 2019 10:26 am

Your PC getting 26, pi3 getting 20, and pi4 getting 15 is pointing to something going on. I would expect the PC to have the most excess power, followed by running the PI3 with an oversized power supply (3A vs 2.5A), followed by the Pi4 running the standard sized power supply for it(3A). The reason I say power is that is the most common problem with USB devices (at least ones that function at all). As I thought I made clear above the Pi 4 (all by itself)draws a LOT more power than the Pi3 series. It is a little odd that you have been running a 3A power supply on your Pi3, the standard for those was only 2.5A. Can you look up what the power draw specs are for that camera? As well as the speed it is supposed to run at (not what it is actually running at). IF it is supposed to be running at 50MB/s (or whatever) and is running slower, it could be pointing to an issue with the camera itself.
Manulobo22
Posts: 21
Joined: Sat Oct 05, 2019 9:28 pm

Re: Worse USB speed on RPI 4 than RPI 3 B

Fri Nov 15, 2019 10:51 pm

Brad Q wrote: ↑
Fri Nov 15, 2019 10:26 am
 Your PC getting 26, pi3 getting 20, and pi4 getting 15 is pointing to something going on. I would expect the PC to have the most excess power, followed by running the PI3 with an oversized power supply (3A vs 2.5A), followed by the Pi4 running the standard sized power supply for it(3A). The reason I say power is that is the most common problem with USB devices (at least ones that function at all). As I thought I made clear above the Pi 4 (all by itself)draws a LOT more power than the Pi3 series. It is a little odd that you have been running a 3A power supply on your Pi3, the standard for those was only 2.5A. Can you look up what the power draw specs are for that camera? As well as the speed it is supposed to run at (not what it is actually running at). IF it is supposed to be running at 50MB/s (or whatever) and is running slower, it could be pointing to an issue with the camera itself.
Hello, I've just been able to connect to the forum.

The Kinect camera needs an external power supply 12V 1.08A, but currently I'm powering it using the official adapter, so there is not a problem. Then Kinect has a common USB 2.0 that you insert to your PC and runs like other device.

I made a battery pack using batteries with 3.7V 1.5A. I made two sub-packs with 3 batteries in parallel, and those sub-packs are connected in series, and then with a stepper down i reduce to 5.25V. I've done this before, and always it works perfectly. So i think that power it isn't a problem, because in addition to what i said, I made an USB-Y, and I gave extra power to the USB-Kinect only, and it all worked the same way.

So if it is an incompatibility issue with the Kinect and the RPI bus, how could i know for sure?
dustnbone
Posts: 259
Joined: Tue Nov 05, 2019 2:49 am

Re: Worse USB speed on RPI 4 than RPI 3 B

Sat Nov 16, 2019 1:28 am

Unplug it and see if the problem goes away?
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