with my canvio basics 2TB USB 3 disk I can get write speeds up to 15MB/s on the ROCK PI 4 with debian 9. Using the USB 2 connector it is 11 MB/s. The power supply should be sufficient, as it is a USB PD supply.
The drive works at expected performance when I connect it to my Notebook.
Does anyone else have problems with USB hdds and low speed?
Do you see anything in dmesg? Also, paste here the output of lsusb and lsusb -t command. I suppose there is issue with uas driver and the chipset in your enclosure.
dmesg shows no errors. Earlier I had power issues (external hdd seems to draw a bit too much for the USB PD supply). Now that I connected the Lenovo USB-C supply of my notebook, the power issue is resolved but the low speed remains.
lsusb -t:
/: Bus 08.Port 1: Dev 1, Class=root_hub, Driver=xhci-hcd/1p, 5000M
/: Bus 07.Port 1: Dev 1, Class=root_hub, Driver=xhci-hcd/1p, 480M
/: Bus 06.Port 1: Dev 1, Class=root_hub, Driver=xhci-hcd/1p, 5000M
|__ Port 1: Dev 2, If 0, Class=Mass Storage, Driver=usb-storage, 5000M
/: Bus 05.Port 1: Dev 1, Class=root_hub, Driver=xhci-hcd/1p, 480M
/: Bus 04.Port 1: Dev 1, Class=root_hub, Driver=ohci-platform/1p, 12M
/: Bus 03.Port 1: Dev 1, Class=root_hub, Driver=ohci-platform/1p, 12M
/: Bus 02.Port 1: Dev 1, Class=root_hub, Driver=ehci-platform/1p, 480M
/: Bus 01.Port 1: Dev 1, Class=root_hub, Driver=ehci-platform/1p, 480M
lsusb:
Bus 006 Device 002: ID 0480:0900 Toshiba America Inc
Bus 006 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 005 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 008 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 007 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 004 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 003 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Well the driver is already the fail-safe option (usb-storage instead of uas). If there is indeed no error messages, it has to be some low-level hardware issue that does not report errors but prohibits proper performance.
I found out about the issue by copying a file over SSH and wondering about the slow speed (GBit LAN). Then I tried copying from sd card to external HDD and found out that that’s the bottleneck. It got more precise with a “dd bs=1M count=1000” from sd to HDD.
Probably the SD card is the limiting factor then… It’s a Samsung Evo 32GB
I am going to use my Rock Pi mainly to receive Backups from LAN and store them on the USB HDD. Is the speed really limited by the SD write performance?
I am going to use my Rock Pi mainly to receive Backups from LAN and store them on the USB HDD. Is the speed really limited by the SD write performance?
The SD card speed should not affect the network to USB speed. What’s the output of
Network speed is not the issue.
My problem is that dd if=/dev/zero of=/home/-user-/tempfile bs=1M count=1000 results in 40MB/s. No network involved, no USB HDD involved.
When writing to the USB 3.0 HDD (Toshiba Canvio Basic) write speed is ~10MB/s.
Measurements with 1GB file:
/dev/zero->SD: 40MB/s
/dev/zero-> USB HDD: 13.6MB/s
SD->/dev/null: 1.4GB/s
USB HDD -> /dev/null: 1.1GB/s
So I just bought a USB Y- cable (2x USB A <-> HDD USB) to check if the issue is due to a single USB port not being able to supply enough current. There was no change however. The USB HDD write speed remains to be around 14 MB/s.