RandyOo
Posts: 34
Joined: Sat Mar 12, 2016 8:16 am

USB 3.0 hubs unreliable on Pi4

Mon Dec 02, 2019 12:56 am

I've had a pretty frustrating experience thus far, in my attempts to set up a reliable Network Attached Storage server on my new Pi4. I've connected two self-powered 12TB WD Easystore external HDDs via a USB 3.0 hub, and have been plagued with intermittent USB disconnects/resets, causing data corruption. I've tested with 3 different hubs, and only one of them has been reliable.

The errors manifest in dmesg:

Code: Select all

Nov 30 00:22:12 rpi4 kernel: [214989.685792] usb 2-1.1.2: reset SuperSpeed Gen 1 USB device number 11 using xhci_hcd
Nov 30 00:22:12 rpi4 kernel: [214989.709485] sd 2:0:0:0: [sdc] tag#0 UNKNOWN(0x2003) Result: hostbyte=0x07 driverbyte=0x00
Nov 30 00:22:12 rpi4 kernel: [214989.709496] sd 2:0:0:0: [sdc] tag#0 CDB: opcode=0x88 88 00 00 00 00 00 40 dc b8 30 00 00 08 00 00 00
Nov 30 00:22:12 rpi4 kernel: [214989.709516] zio pool=pool vdev=/dev/sdc1 error=5 type=1 offset=557160882176 size=1048576 flags=40080cb0
Nov 30 07:41:13 rpi4 kernel: [241330.541219] usb 2-1.1.1: USB disconnect, device number 10
Nov 30 07:41:13 rpi4 kernel: [241330.541721] sd 1:0:0:0: [sdb] tag#0 UNKNOWN(0x2003) Result: hostbyte=0x07 driverbyte=0x00
Nov 30 07:41:13 rpi4 kernel: [241330.541729] sd 1:0:0:0: [sdb] tag#0 CDB: opcode=0x88 88 00 00 00 00 04 12 f8 11 18 00 00 08 00 00 00
Nov 30 07:41:13 rpi4 kernel: [241330.541746] zio pool=pool vdev=/dev/sdb1 error=5 type=1 offset=8959034535936 size=1048576 flags=40080cb0
*snip*
Nov 30 07:41:13 rpi4 kernel: [241330.542174] zio pool=pool vdev=/dev/sdb1 error=5 type=1 offset=8959040827392 size=1048576 flags=40080cb0
Nov 30 07:41:16 rpi4 kernel: [241333.757171] usb 2-1.1.1: new SuperSpeed Gen 1 USB device number 12 using xhci_hcd
A zpool scrub comes up with both read and checksum errors.

I should probably point out that it's running the 64-bit kernel:

Code: Select all

root@rpi4:/home/pi# uname -a
Linux rpi4 4.19.83-v8+ #1277 SMP PREEMPT Mon Nov 11 16:53:30 GMT 2019 aarch64 GNU/Linux
Thus far, I've tried out 3 different hubs:
  • Anker A7516 (unpowered) Bus 002 ID 0bda:0411/Bus 001 ID 0bda:5411 Realtek Semiconductor Corp.
    error-free for about 36 hours/4TB transferred, then errors as above
  • atolla 207 (powered) Bus 002 Device 008: ID 045b:0210/Bus 001 ID 045b:0209 Hitachi, Ltd
    error-free for only 3 hours, then errors as above
  • Anker (unpowered) with Via Labs VL812 chipset Bus 002 ID 2109:0812/Bus 001 ID 2109:2812 VIA Labs, Inc. VL812 Hub
    error-free for >7 days thus far, >30TB transferred
Since the reliable one isn't a powered hub, and one of the unreliable ones is, it seems pretty clear that power isn't the underlying issue. I did read this sticky, but the symptoms and error messages don't line up at all, so I doubt UAS is the cause, but I haven't yet enabled the "usb-storage.quirks" option to verify.

I'm mainly sharing this information in the hopes that it will help others, either in finding themselves a usable USB hub, or in resolving whatever the underlying issue is. Now that I've found what appears to be a reliable hub, I'll likely purchase a powered hub that shares the same VL812 chipset.

I'd be interested in learning others' experiences with USB hubs. I did find this page, but it doesn't seem to be updated for the Pi4/USB 3.0.

andrum99
Posts: 1207
Joined: Fri Jul 20, 2012 2:41 pm

Re: USB 3.0 hubs unreliable on Pi4

Mon Dec 02, 2019 9:45 pm

I've also seen occasional problems when using ZFS on a Dlink DUB-1340 power USB 3.0 hub - vid:pid is 05e3:0617

ZFS copes fine with the UAS errors I'm seeing - there is just a delay shown in 'zpool events'. In my case the errors are UAS errors, not USB.

RandyOo
Posts: 34
Joined: Sat Mar 12, 2016 8:16 am

Re: USB 3.0 hubs unreliable on Pi4

Tue Dec 03, 2019 11:21 pm

A quick update: I've pumped another 30TB of data through the USB port using the USB hub with the VL812 chipset, with no issues. Powered hubs based on the VL812 seem pretty spendy, but I found an affordable hub that has the option of being powered through a micro USB port and is based on the VL817, which appears to be the current replacement for the VL812. It just arrived, so I'll test it out for a few days and see what happens. VID/PID is 2109:0817.

andersdk
Posts: 28
Joined: Sun Feb 03, 2019 8:29 pm

Re: USB 3.0 hubs unreliable on Pi4

Tue Dec 03, 2019 11:28 pm

It should be possible to power any USB hub via a USB male A to male A from a standard USB supply.
These cables are available from AliExpress, Ebay etc.
This will of course take up that one hub port used only for power connection.

If you are handy with a soldering iron, you can always open the hub and solder in an extra cable used only for USB power.

RandyOo
Posts: 34
Joined: Sat Mar 12, 2016 8:16 am

Re: USB 3.0 hubs unreliable on Pi4

Tue Dec 03, 2019 11:40 pm

andersdk wrote:
Tue Dec 03, 2019 11:28 pm
It should be possible to power any USB hub via a USB male A to male A from a standard USB supply.
These cables are available from AliExpress, Ebay etc.
This will of course take up that one hub port used only for power connection.

If you are handy with a soldering iron, you can always open the hub and solder in an extra cable used only for USB power.
Yep! A gender-changing adapter would be another option. But it's my understanding that backfeeding the host port can be problematic, and so I was glad to see a reviewer had already tested and confirmed that isn't an issue with this particular model. I'll be very glad if this device proves to work as reliably as the VL812-based hub did.

andersdk
Posts: 28
Joined: Sun Feb 03, 2019 8:29 pm

Re: USB 3.0 hubs unreliable on Pi4

Wed Dec 04, 2019 12:15 am

I do not (yet) have a Pi4.
On my Pi's (zero, 1B, 1B+ ,2B, 3B) its not a problem backfeeding power via the USB to my experience
Provided your PSU this way in has enough umph, you can run the Pi off this power.

Its best to use the dedicated OTG power port to avoid any sudden power loss if you need to alter the USB connections

RandyOo
Posts: 34
Joined: Sat Mar 12, 2016 8:16 am

Re: USB 3.0 hubs unreliable on Pi4

Thu Dec 12, 2019 4:07 am

andersdk wrote:
Wed Dec 04, 2019 12:15 am
I do not (yet) have a Pi4.
On my Pi's (zero, 1B, 1B+ ,2B, 3B) its not a problem backfeeding power via the USB to my experience
Provided your PSU this way in has enough umph, you can run the Pi off this power.

Its best to use the dedicated OTG power port to avoid any sudden power loss if you need to alter the USB connections
I've just purchased a cheap USB hub that backfeeds power, and my experience confirms that it prevents the Pi from rebooting, right up until I remove the power source from the hub. I intent to block or snip the 5v on the cable between the Pi and the hub to solve this issue.

Meanwhile, there is a bigger problem: every single USB hub I've tried thus far has been unreliable, causing USB device resets and corresponding I/O errors on the connected disks. This issue has persisted intermittently across three different disks, and four different hubs (including the VL817 I previously alluded to, and a VL813 mentioned below). Disks are self-powered, but providing an external power source to the hub doesn't seem to matter, regardless.

The hub that worked flawlessly eventually generated a device reset after about 5 days of cumulative service. The newest hub was supposed to be based on the VL812, but turned out to be a VL813. After about 1.5 days and 20TB transferred, another reset (and I/O error) happened.

At this point, I'm beginning to wonder if my Pi has a hardware fault, or if there is an issue with the USB driver on the 64-bit kernel. I've now enabled the "USB storage quirks" to disable UAS, and will see if it makes a difference.

jamesh
Raspberry Pi Engineer & Forum Moderator
Raspberry Pi Engineer & Forum Moderator
Posts: 26447
Joined: Sat Jul 30, 2011 7:41 pm

Re: USB 3.0 hubs unreliable on Pi4

Fri Dec 13, 2019 11:18 am

RandyOo wrote:
Thu Dec 12, 2019 4:07 am
andersdk wrote:
Wed Dec 04, 2019 12:15 am
I do not (yet) have a Pi4.
On my Pi's (zero, 1B, 1B+ ,2B, 3B) its not a problem backfeeding power via the USB to my experience
Provided your PSU this way in has enough umph, you can run the Pi off this power.

Its best to use the dedicated OTG power port to avoid any sudden power loss if you need to alter the USB connections
I've just purchased a cheap USB hub that backfeeds power, and my experience confirms that it prevents the Pi from rebooting, right up until I remove the power source from the hub. I intent to block or snip the 5v on the cable between the Pi and the hub to solve this issue.

Meanwhile, there is a bigger problem: every single USB hub I've tried thus far has been unreliable, causing USB device resets and corresponding I/O errors on the connected disks. This issue has persisted intermittently across three different disks, and four different hubs (including the VL817 I previously alluded to, and a VL813 mentioned below). Disks are self-powered, but providing an external power source to the hub doesn't seem to matter, regardless.

The hub that worked flawlessly eventually generated a device reset after about 5 days of cumulative service. The newest hub was supposed to be based on the VL812, but turned out to be a VL813. After about 1.5 days and 20TB transferred, another reset (and I/O error) happened.

At this point, I'm beginning to wonder if my Pi has a hardware fault, or if there is an issue with the USB driver on the 64-bit kernel. I've now enabled the "USB storage quirks" to disable UAS, and will see if it makes a difference.
The 64 bit kernel is still beta, so would be interested to know if you see the same problems with the 32bit kernel. Meanwhile, I'm trying to locate similar hubs so we can do some internal testing.
Principal Software Engineer at Raspberry Pi (Trading) Ltd.
Contrary to popular belief, humorous signatures are allowed.
I've been saying "Mucho" to my Spanish friend a lot more lately. It means a lot to him.

RandyOo
Posts: 34
Joined: Sat Mar 12, 2016 8:16 am

Re: USB 3.0 hubs unreliable on Pi4

Fri Dec 13, 2019 3:30 pm

jamesh wrote:
Fri Dec 13, 2019 11:18 am
The 64 bit kernel is still beta, so would be interested to know if you see the same problems with the 32bit kernel. Meanwhile, I'm trying to locate similar hubs so we can do some internal testing.
Well, firstly, I've seen the issue with UAS disabled/USB storage quirks enabled, so that can also be ruled out.

It has been incredibly frustrating trying to troubleshoot this issue, owing to the intermittent nature of the issue, and how it can sometimes take days to show up.

I'm not yet able to say this with confidence (hard to prove a negative), but I think I may have found the trigger: smartmontools. I'm not really sure how the hubs come into the picture--they may have just been a distraction. I've not done much testing of directly-connected drives, since I need multiple drives for this project. Also didn't spend much time on the 32 bit kernel, since I was having those Out-of-Memory errors, and ZFS is better off with a 64 bit kernel anyway. Nor have I tested a great variety of different controllers. It may just be the unique combination of these controllers with smartmontools.

I'll continue testing, and see if I can get the issue to surface with smartmontools uninstalled, and report back here.

RandyOo
Posts: 34
Joined: Sat Mar 12, 2016 8:16 am

Re: USB 3.0 hubs unreliable on Pi4

Fri Dec 20, 2019 10:01 pm

RandyOo wrote:
Fri Dec 13, 2019 3:30 pm
I'll continue testing, and see if I can get the issue to surface with smartmontools uninstalled, and report back here.
I've replicated the issue both with and without smartmontools, so that theory can be discarded. I've also seen it happen on the 32 bit kernel. usbquirks didn't help, either.

I'm willing to try to capture debug data, but I'm not really sure how to go about it...

xr8RGBNj
Posts: 2
Joined: Thu Jan 23, 2020 6:16 pm

Re: USB 3.0 hubs unreliable on Pi4

Thu Jan 23, 2020 6:20 pm

Has anyone made some headway on this issue? I'm also experiencing issues with an Amazon Basics USB 3.0 Powered hub.

Original configuration was as follows
RPi 4 / 4GB -> USB HUB
USB HUB -> Disk1
USB HUB -> Disk2

Changed to this configuration
RPi 4 / 4GB -> USB HUB
RPi 4 / 4GB -> Disk1
USB HUB -> Disk2 // This disk began to have Faults

Changed to this configuration
RPi 4 / 4GB -> USB HUB
RPi 4 / 4GB -> Disk2 // Disk no longer had faults
USB HUB -> Disk1 // This disk began to have Faults

RandyOo
Posts: 34
Joined: Sat Mar 12, 2016 8:16 am

Re: USB 3.0 hubs unreliable on Pi4

Thu Jan 23, 2020 6:40 pm

xr8RGBNj wrote:
Thu Jan 23, 2020 6:20 pm
Has anyone made some headway on this issue? I'm also experiencing issues with an Amazon Basics USB 3.0 Powered hub.

Original configuration was as follows
RPi 4 / 4GB -> USB HUB
USB HUB -> Disk1
USB HUB -> Disk2
I assume you had faults in the original config? Are you getting the same faults I had, ie "USB disconnect"? Not knowing how to debug the issue, and with jamesh stating they'd be doing their own testing, I've given up, for now. ZFS is able to handle the disconnect (and ensuing corruption), and it's only happened once since I've placed the drives into normal service, and stopped stress testing them and the USB interface.

I'd put my money on a rare/intermittent issue on the ARM Linux kernel USB driver that only surfaces when the interface is pushed to a sustained 100% usage, but the difficulty in replicating it will make it hard bug to squash. Also: it would be nice to know what the chipset of your hub is (obtainable with the "lsusb" command).

mcmanuf
Posts: 44
Joined: Wed Aug 22, 2012 12:29 am

Re: USB 3.0 hubs unreliable on Pi4

Mon Jan 27, 2020 5:24 pm

I for one, is very saddened, that as of now, there does not exist 1x single powered usb3.0 hub, that agreed upon, that actually works flawlessly with the RPI4.

Will monitor this thread closely.

I have asked in amazon qa for the anker powered hub, but not sure people understand correctly.
https://www.amazon.de/dp/B0192W3HX8/ref ... 69ab0086b2

smoyth
Posts: 1
Joined: Mon Feb 03, 2020 4:29 pm

Re: USB 3.0 hubs unreliable on Pi4

Mon Feb 03, 2020 5:07 pm

I think I am seeing the same issue but with a USB3 NVMe enclosure instead of a hub. Similar errors in dmesg, intermittent failures after long periods.

I notice that it tends to drop when I interact with it after a long period. Specifically when I hit the web app I'm serving whose files are located on the disk.

I'm continuing to experiment. Some things I've tried:

* Several different enclosures (with one, the disk would disappear entirely)
* Different cables

More things I'll try:

* Updating firmware (just did this)
* USB 2 port instead of USB 3 (this would not be an acceptable long term solution, but I'm curious)
* Not touching the disk at all (I tend to touch it gently to see how hot it is when I first come into my office, maybe this is causing an issue; again, would not be acceptable but I'm curious)

RandyOo
Posts: 34
Joined: Sat Mar 12, 2016 8:16 am

Re: USB 3.0 hubs unreliable on Pi4

Mon Feb 03, 2020 6:56 pm

smoyth wrote:
Mon Feb 03, 2020 5:07 pm
I think I am seeing the same issue but with a USB3 NVMe enclosure instead of a hub. Similar errors in dmesg, intermittent failures after long periods.
Did you happen to try disabling UAS, as suggested in the sticky that I referenced in my first post in this thread? What specific errors did you see in dmesg?

ejolson
Posts: 5205
Joined: Tue Mar 18, 2014 11:47 am

Re: USB 3.0 hubs unreliable on Pi4

Mon Feb 03, 2020 7:26 pm

RandyOo wrote:
Mon Feb 03, 2020 6:56 pm
smoyth wrote:
Mon Feb 03, 2020 5:07 pm
I think I am seeing the same issue but with a USB3 NVMe enclosure instead of a hub. Similar errors in dmesg, intermittent failures after long periods.
Did you happen to try disabling UAS, as suggested in the sticky that I referenced in my first post in this thread? What specific errors did you see in dmesg?
I suspect the unexpected disconnect and reconnect reported in

https://www.raspberrypi.org/forums/view ... 6&t=263618

is another example of the same problem discussed here.

Could there be noise on the USB cables? Are they shielded? Maybe they pick up RF interference that leads to a disconnect.

Since the SBCs from a competitor seem delayed due to a certain non-computer related virus, I was contemplating some Pi 4Bs with USB-attached SSD drives for setting up a quieter NFS file server than what is currently running in my office.

It is good to know when not stressed that the system appears stable. At the same time, since the noisy PC-based solution is running on hardware well-tested over the last 10 years, it is tempting to put up with the noise a little longer until the bathtub is completely empty.

emma1997
Posts: 774
Joined: Sun Nov 08, 2015 7:00 pm
Location: New England (not that old one)

Re: USB 3.0 hubs unreliable on Pi4

Mon Feb 03, 2020 9:06 pm

smoyth wrote:
Mon Feb 03, 2020 5:07 pm
* USB 2 port instead of USB 3 (this would not be an acceptable long term solution, but I'm curious)
That is what I am currently forced to do as a long term solution since learning the Pi4 USB3 does not work reliably with the most common low cost SATA interfaces (fine on USB2 or other Pi and PCs). In fact lost a years worth of media but blame only myself for failure to back up and relying on an untested platform. Hopefully this is not a Pi4 hardware defect and is fixable in software.

In this situation it would serve as a very easy but important diagnostic tool.

andrum99
Posts: 1207
Joined: Fri Jul 20, 2012 2:41 pm

Re: USB 3.0 hubs unreliable on Pi4

Mon Feb 03, 2020 11:07 pm

emma1997 wrote:
Mon Feb 03, 2020 9:06 pm
smoyth wrote:
Mon Feb 03, 2020 5:07 pm
* USB 2 port instead of USB 3 (this would not be an acceptable long term solution, but I'm curious)
That is what I am currently forced to do as a long term solution since learning the Pi4 USB3 does not work reliably with the most common low cost SATA interfaces (fine on USB2 or other Pi and PCs).
Have you tried using different / better adaptors? Not sure what sort of drives you are attaching, but I've got startech.com USB 3.0 hard disk enclosures, both 2.5" and 3.5", and they work fine with spinning rust - I would certainly recommend them for that. I've not tried them with SSDs. The 2.5" enclosure is the S2510BMU33, 3.5" is S3510BMU33. They're not the cheapest, but they've been rock solid reliable for me so far with the PI 4B. They also work fine on the Pi 3B and 3B+, although they're obviously limited to USB 2.0 on those older Pis.

emma1997
Posts: 774
Joined: Sun Nov 08, 2015 7:00 pm
Location: New England (not that old one)

Re: USB 3.0 hubs unreliable on Pi4

Tue Feb 04, 2020 12:27 am

andrum99 wrote:
Mon Feb 03, 2020 11:07 pm
Have you tried using different / better adaptors?
Different, yes. Out of quite a large number units (mine/friends/family) representing half dozen chipsets only 2 passed. Some DOA, some failed after few minutes. All working on USB2 or PC. Of course, bargain hunter that I am, there were finds that didn't work on anything but those didn't count (didn't have to pay for them either, thank you Ebay).

Enclosure vs cable adapters didn't factor. A couple different HD and several models SSD models didn't matter either. As already hinted here it's the SATA IC, not drive or case.

Recently deciding to backup all my drives (some 60 terabytes!) gave me a chance to run these tests. For now it's USB2 for SATA, USB3 for kbd/mouse dongle and/or portable HDDs. It's why I characterize my Pi4 as having only 2 1/2 or 3 ports at best. Still a bargain and my favorite SBC. Quite happy considering.

BTW I have two Pi4-4g and three Pi4-1g now so not mfg defect. Maybe updating again will help. IDK. Anyway I have faith the Pi team will eventually get to the bottom of this if not already.

RandyOo
Posts: 34
Joined: Sat Mar 12, 2016 8:16 am

Re: USB 3.0 hubs unreliable on Pi4

Tue Feb 04, 2020 3:41 am

emma1997 wrote:
Tue Feb 04, 2020 12:27 am
andrum99 wrote:
Mon Feb 03, 2020 11:07 pm
Have you tried using different / better adaptors?
Different, yes. Out of quite a large number units (mine/friends/family) representing half dozen chipsets only 2 passed. Some DOA, some failed after few minutes. All working on USB2 or PC. Of course, bargain hunter that I am, there were finds that didn't work on anything but those didn't count (didn't have to pay for them either, thank you Ebay).

Enclosure vs cable adapters didn't factor. A couple different HD and several models SSD models didn't matter either. As already hinted here it's the SATA IC, not drive or case.
For what it's worth, this one has been working fine on USB 3.0, running my system root off an SSD:
174c:55aa ASMedia Technology Inc. Name: ASM1051E SATA 6Gb/s bridge

I seem to remember it being fairly cheap, and have had exactly zero issues with it, when directly connected. Same goes for several WD external drives. They only seem to cause trouble when they're connected through a hub, otherwise seemed to be perfectly reliable when connected directly to the Pi.

ejolson
Posts: 5205
Joined: Tue Mar 18, 2014 11:47 am

Re: USB 3.0 hubs unreliable on Pi4

Tue Feb 04, 2020 4:42 am

RandyOo wrote:
Thu Jan 23, 2020 6:40 pm
I assume you had faults in the original config? Are you getting the same faults I had, ie "USB disconnect"? Not knowing how to debug the issue, and with jamesh stating they'd be doing their own testing, I've given up, for now. ZFS is able to handle the disconnect (and ensuing corruption), and it's only happened once since I've placed the drives into normal service, and stopped stress testing them and the USB interface.

I'd put my money on a rare/intermittent issue on the ARM Linux kernel USB driver that only surfaces when the interface is pushed to a sustained 100% usage, but the difficulty in replicating it will make it hard bug to squash. Also: it would be nice to know what the chipset of your hub is (obtainable with the "lsusb" command).
I wonder if the disconnect could be an overheating problem with the VLI chip on the Pi which manages the USB. Have you tried cooling (maybe by placing the Pi vertically with a fan blowing on it) to see if all the problems just go away?

Maybe the power-saving changes in the most recent firmware are to blame. Is there any way to downgrade to the old firmware to check?

By the way, are you coping the 60TB of data from one pool to another all over USB or is the data being copied from another computer using Ethernet?

RandyOo
Posts: 34
Joined: Sat Mar 12, 2016 8:16 am

Re: USB 3.0 hubs unreliable on Pi4

Tue Feb 04, 2020 5:25 am

ejolson wrote:
Tue Feb 04, 2020 4:42 am
I wonder if the disconnect could be an overheating problem with the VLI chip on the Pi which manages the USB. Have you tried cooling (maybe by placing the Pi vertically with a fan blowing on it) to see if all the problems just go away?

Maybe the power-saving changes in the most recent firmware are to blame. Is there any way to downgrade to the old firmware to check?

By the way, are you coping the 60TB of data from one pool to another all over USB or is the data being copied from another computer using Ethernet?
I've not tried active cooling, but the Pi is in one of those metal cases, and I applied thermal paste where it makes contact with the SoC (and another IC that I haven't identified). It seems to do a good job of cooling. I actually shared your previously posted theory about noise... Just not sure how I could go about testing it (or mitigating it)?

At present, I don't really have lots of time to spend experimenting, and it really is quite difficult to duplicate. It's been stable ever since I've quit "stress-testing", and finished implementation of my project. If there was a simple way to switch to another firmware, I'd be willing to give it a try. I really hate to attempt to intentionally induce failures now the file server is in active use, though.

I was mostly testing by running a zpool scrub, which causes the entire contents of all the ZFS member drives to be read, and parity checksum calculated and checked, so it's intensive use of the USB interface and CPU. I've had it happen just by "copying" the contents of the drives to /dev/null, though, so I doubt the CPU usage is a factor.

andrum99
Posts: 1207
Joined: Fri Jul 20, 2012 2:41 pm

Re: USB 3.0 hubs unreliable on Pi4

Tue Feb 04, 2020 5:10 pm

emma1997 wrote:
Tue Feb 04, 2020 12:27 am
andrum99 wrote:
Mon Feb 03, 2020 11:07 pm
Have you tried using different / better adaptors?
Different, yes. Out of quite a large number units (mine/friends/family) representing half dozen chipsets only 2 passed.
I would be interested to know which 2 chipsets passed. I'm assuming by "passed" you mean "works reliably"?

ejolson
Posts: 5205
Joined: Tue Mar 18, 2014 11:47 am

Re: USB 3.0 hubs unreliable on Pi4

Tue Feb 04, 2020 5:29 pm

andrum99 wrote:
Tue Feb 04, 2020 5:10 pm
emma1997 wrote:
Tue Feb 04, 2020 12:27 am
andrum99 wrote:
Mon Feb 03, 2020 11:07 pm
Have you tried using different / better adaptors?
Different, yes. Out of quite a large number units (mine/friends/family) representing half dozen chipsets only 2 passed.
I would be interested to know which 2 chipsets passed. I'm assuming by "passed" you mean "works reliably"?
My understanding of USB is that the link layer automatically tries three times if a bad CRC is obtained when trying to send a packet before giving up. What to do next appears user defined and in the present case plausibly results in disconnecting the device.

Could there be a parameter that tells the Linux device driver to keep trying for a bit longer in the presence of more than three CRC errors?

More information on bit errors is in

https://www.raspberrypi.org/forums/view ... 3#p1606283

It is also possible that the big heat sink which so effectively cools the SOC and RAM is restricting air flow around the VLI chip used for the USB and causing it to fail under high loads.

sismindi
Posts: 4
Joined: Mon Feb 10, 2020 2:37 pm

Re: USB 3.0 hubs unreliable on Pi4

Mon Feb 10, 2020 2:40 pm

Hi. Same problem with a hub usb simpolar and 2 hdd and 2 ssd.

News?

Return to “Troubleshooting”