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PythonEater

Member

From: Kentucky, USA

Registered: 2010-08-19

Posts: 34

USB Read/Write Speed is Incredibly Slow

I started a thread in the hardware section on the Ubuntu Forums, but I've narrowed it down to being a software issue. The guys over on the Ubuntu forum weren't all that helpful, and I'm hoping you guys can help me out.

The problem is that all USB storage devices are written to at about 1MB/s, and is read at an equally slow speed.

After testing my computer on an older Ubuntu release (8.04 32bit), I verified it wasn't a hardware issue, because the read and write speeds were like they were supposed to be. Then, I downloaded the 32bit release of the Ubuntu version I'm currently using (an up-to-date version of Natty) and booted the live cd of it. It was equally slow there as well.

The read/write speeds are also bad on openSUSE and Arch (I installed Ubuntu to try out Unity), so I don't think that it's an issue with Ubuntu, as much as it seems like a kernel issue.

At this point, I don't know where to go. Maybe a bug report to the kernel devs? I'm not sure. Any help would be great!

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"You can just deny pain… until infection leads to amputation. Then it’s really gone."
    --Craig Benzine

Inxsible

Forum Fellow

From: Chicago

Registered: 2008-06-09

Posts: 9,183

Re: USB Read/Write Speed is Incredibly Slow

It'd be mighty difficult to see what the problem is void of any sort of information.

Is the usb 2.x or 1.x? What DE or WM are you using? Are you using the same in all distros that you have tried?

Since you think it is a kernel issue-- what version of the kernel are you using in the distros? the same across all of them I assume.

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PythonEater

Member

From: Kentucky, USA

Registered: 2010-08-19

Posts: 34

Re: USB Read/Write Speed is Incredibly Slow

Sorry, I posted this earlier, so I forgot.

Anyway, it's

1) USB 2.0
2) I've tested this in KDE, GNOME, and from the command line
3) I've tried all 3 of the previous methods in all distros I've tried
4) I've used 2.6.37 and 2.6.38, and experienced the same speed in all of them.

In case you're wondering, I've tested the speeds on 2 SanDisk cruzer flash drives, an HP flash drive, and a Western Digital external hard drive.

---

"You can just deny pain… until infection leads to amputation. Then it’s really gone."
    --Craig Benzine

Inxsible

Forum Fellow

From: Chicago

Registered: 2008-06-09

Posts: 9,183

Re: USB Read/Write Speed is Incredibly Slow

me thinks that this has probably nothing to do with the kernel because otherwise there would be a lot of people complaining about this. I use the 2.6.38 kernel without issues.

having said that, I would say try to move a big file to and from the usb and check htop or any system monitor to see if the cpu cycles are being whittled away by any particular process. I am afraid, most of this will have to be trial and error until a culprit is found across the various distros that you use.

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PythonEater

Member

From: Kentucky, USA

Registered: 2010-08-19

Posts: 34

Re: USB Read/Write Speed is Incredibly Slow

Alright, I'll post any updates if I find a culprit. Thanks.

---

"You can just deny pain… until infection leads to amputation. Then it’s really gone."
    --Craig Benzine

PythonEater

Member

From: Kentucky, USA

Registered: 2010-08-19

Posts: 34

Re: USB Read/Write Speed is Incredibly Slow

Okay, I'm not sure what most of the output in dmesg is, but is this a problem?

[ 4245.461623] sd 6:0:0:0: [sdc] 7897087 512-byte logical blocks: (4.04 GB/3.76 GiB)
[ 4245.468519] sd 6:0:0:0: [sdc] Write Protect is off
[ 4245.468527] sd 6:0:0:0: [sdc] Mode Sense: 00 00 00 00
[ 4245.475522] sd 6:0:0:0: [sdc] Asking for cache data failed
[ 4245.475529] sd 6:0:0:0: [sdc] Assuming drive cache: write through
[ 4245.511616] sd 6:0:0:0: [sdc] Asking for cache data failed
[ 4245.511627] sd 6:0:0:0: [sdc] Assuming drive cache: write through
[ 4245.610590]  sdc: sdc1
[ 4245.807550] sd 6:0:0:0: [sdc] Asking for cache data failed
[ 4245.807561] sd 6:0:0:0: [sdc] Assuming drive cache: write through
[ 4245.807569] sd 6:0:0:0: [sdc] Attached SCSI removable disk

There's a lot of the word failed there

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"You can just deny pain… until infection leads to amputation. Then it’s really gone."
    --Craig Benzine

brebs

Member

Registered: 2007-04-03

Posts: 3,742

Re: USB Read/Write Speed is Incredibly Slow

What are the mount options? Run "mount" to see, while the drive is mounted.

"sync" is bad, but "flush" is good.

PythonEater

Member

From: Kentucky, USA

Registered: 2010-08-19

Posts: 34

Re: USB Read/Write Speed is Incredibly Slow

The options are

/dev/sdc1 on /media/B463-99DF_ type vfat (rw,nosuid,nodev,uhelper=udisks,uid=1000,gid=1000,shortname=mixed,dmask=0077,utf8=1,showexec,flush)

so that seems to be fine.

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"You can just deny pain… until infection leads to amputation. Then it’s really gone."
    --Craig Benzine

premier

Member

Registered: 2006-12-07

Posts: 16

Re: USB Read/Write Speed is Incredibly Slow

Something is wrong with your USB high speed.  1 MB/sec is the fastest throughput you can get at USB full speed.

A quick test I was able to run:

System info

$ lsusb
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 002 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 003 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 004 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 001 Device 002: ID 0409:005a NEC Corp. HighSpeed Hub
Bus 003 Device 002: ID 046d:c044 Logitech, Inc. LX3 Optical Mouse
Bus 001 Device 004: ID 0a5c:4500 Broadcom Corp. BCM2046B1 USB 2.0 Hub (part of BCM2046 Bluetooth)
Bus 001 Device 005: ID 0a5c:4502 Broadcom Corp. Keyboard (Boot Interface Subclass)
Bus 001 Device 006: ID 0a5c:4503 Broadcom Corp. Mouse (Boot Interface Subclass)
Bus 001 Device 007: ID 0a5c:2148 Broadcom Corp. BCM92046DG-CL1ROM Bluetooth 2.1 Adapter
Bus 001 Device 009: ID 0781:5151 SanDisk Corp. Cruzer Micro Flash Drive

$  uname -a
Linux chocolate 2.6.37-ARCH #1 SMP PREEMPT Fri Mar 25 14:35:13 UTC 2011 i686 Intel(R) Pentium(R) 4 CPU 3.06GHz GenuineIntel GNU/Linux

The test

$  sudo hdparm -t /dev/sdb2

/dev/sdb2:
 Timing buffered disk reads:  50 MB in  3.10 seconds =  16.15 MB/sec

Disabling USB high speed controller

$ sudo modprobe -r ehci_hcd

Again:

$  sudo hdparm -t /dev/sdb2

/dev/sdb2:
 Timing buffered disk reads:   4 MB in  4.52 seconds = 905.44 kB/sec

PythonEater

Member

From: Kentucky, USA

Registered: 2010-08-19

Posts: 34

Re: USB Read/Write Speed is Incredibly Slow

That seems like what the problem is. Running lsmod, there is no mention of ehci_hcd (or when greping through it, no mention of hcd at all. I would think that the module would be named the same in Ubuntu.), and running the command that you did, i get

$ sudo hdparm -t /dev/sdc1

/dev/sdc1:
 Timing buffered disk reads:   4 MB in  4.22 seconds = 970.67 kB/sec

While this is a result, modprobing ehci_hcd does nothing (I didn't expect it to), so I still am lost as to how to fix this. If it matters, the output of lsusb:

$ lsusb
Bus 004 Device 010: ID 03f0:2a07 Hewlett-Packard 
Bus 004 Device 009: ID 0461:4d20 Primax Electronics, Ltd 
Bus 004 Device 003: ID 04f2:b091 Chicony Electronics Co., Ltd Webcam
Bus 004 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 003 Device 002: ID 0bda:0158 Realtek Semiconductor Corp. USB 2.0 multicard reader
Bus 003 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 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub

UPDATE:
Just decided to grep through dmesg with "usb" and got the following:

$ dmesg | grep usb
[    0.482758] usbcore: registered new interface driver usbfs
[    0.482772] usbcore: registered new interface driver hub
[    0.482816] usbcore: registered new device driver usb
[    1.760058] usb 3-1: new full speed USB device using ohci_hcd and address 2
[    1.975307] usb 3-1: not running at top speed; connect to a high speed hub
[    2.016334] usbcore: registered new interface driver uas
[    2.023098] scsi2 : usb-storage 3-1:1.0
[    2.023239] usbcore: registered new interface driver usb-storage
[    2.190036] usb 4-1: new low speed USB device using ohci_hcd and address 2
[    2.584406] input: USB Optical Mouse as /devices/pci0000:00/0000:00:04.0/usb4/4-1/4-1:1.0/input/input5
[    2.584561] generic-usb 0003:0461:4D20.0001: input,hidraw0: USB HID v1.11 Mouse [USB Optical Mouse] on usb-0000:00:04.0-1/input0
[    2.584593] usbcore: registered new interface driver usbhid
[    2.584596] usbhid: USB HID core driver
[    2.590050] usb 4-2: new full speed USB device using ohci_hcd and address 3
[    2.805066] usb 4-2: not running at top speed; connect to a high speed hub
[   21.184791] input: CNF7047 as /devices/pci0000:00/0000:00:04.0/usb4/4-2/4-2:1.0/input/input8
[   21.185871] usbcore: registered new interface driver uvcvideo
[  806.040480] usb 4-4: new full speed USB device using ohci_hcd and address 4
[  806.258218] usb 4-4: not running at top speed; connect to a high speed hub
[  806.287630] scsi5 : usb-storage 4-4:1.0
[ 1558.481866] usb 4-4: USB disconnect, address 4
[ 1566.400374] usb 4-4: new full speed USB device using ohci_hcd and address 5
[ 1566.618376] usb 4-4: not running at top speed; connect to a high speed hub
[ 1566.645809] scsi6 : usb-storage 4-4:1.0
[ 3110.312541] usb 4-4: USB disconnect, address 5
[ 5640.650628] usb 4-4: new full speed USB device using ohci_hcd and address 6
[ 5640.864384] usb 4-4: not running at top speed; connect to a high speed hub
[ 5640.887872] scsi7 : usb-storage 4-4:1.0
[12733.623200] usb 4-4: USB disconnect, address 6
[12737.157305] usb 4-1: USB disconnect, address 2
[12739.550272] usb 4-1: new full speed USB device using ohci_hcd and address 7
[12739.765365] usb 4-1: not running at top speed; connect to a high speed hub
[12739.789798] scsi8 : usb-storage 4-1:1.0
[12773.025821] usb 4-1: USB disconnect, address 7
[12775.780199] usb 4-3: new full speed USB device using ohci_hcd and address 8
[12775.995428] usb 4-3: not running at top speed; connect to a high speed hub
[12776.018766] scsi9 : usb-storage 4-3:1.0
[12777.960147] usb 4-1: new low speed USB device using ohci_hcd and address 9
[12778.203149] input: USB Optical Mouse as /devices/pci0000:00/0000:00:04.0/usb4/4-1/4-1:1.0/input/input13
[12778.203565] generic-usb 0003:0461:4D20.0002: input,hidraw0: USB HID v1.11 Mouse [USB Optical Mouse] on usb-0000:00:04.0-1/input0
[12859.043531] usb 4-3: USB disconnect, address 8
[12860.510052] usb 4-3: new full speed USB device using ohci_hcd and address 10
[12860.724409] usb 4-3: not running at top speed; connect to a high speed hub
[12860.760026] scsi10 : usb-storage 4-3:1.0
[13476.285262] usb 4-3: USB disconnect, address 10

The face that it says that it's not connected to a high speed hub bothers me. The computer is modern(ish), and all the ports are usb 2 compatible.

More UPDATE:
lspci does show the usb 2 devices

00:02.0 USB Controller: nVidia Corporation MCP78S [GeForce 8200] OHCI USB 1.1 Controller (rev a1)
00:02.1 USB Controller: nVidia Corporation MCP78S [GeForce 8200] EHCI USB 2.0 Controller (rev a1)
00:04.0 USB Controller: nVidia Corporation MCP78S [GeForce 8200] OHCI USB 1.1 Controller (rev a1)
00:04.1 USB Controller: nVidia Corporation MCP78S [GeForce 8200] EHCI USB 2.0 Controller (rev a1)

Last edited by PythonEater (2011-04-15 01:37:06)

---

"You can just deny pain… until infection leads to amputation. Then it’s really gone."
    --Craig Benzine

premier

Member

Registered: 2006-12-07

Posts: 16

Re: USB Read/Write Speed is Incredibly Slow

Your device (I'm assuming is the HP device on bus 004) is connected to a USB 1.1 hub.  USB 1.1 doesn't support high speed.  Try a different USB port.

$ lsusb
Bus 004 Device 010: ID 03f0:2a07 Hewlett-Packard
Bus 004 Device 009: ID 0461:4d20 Primax Electronics, Ltd
Bus 004 Device 003: ID 04f2:b091 Chicony Electronics Co., Ltd Webcam
Bus 004 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 003 Device 002: ID 0bda:0158 Realtek Semiconductor Corp. USB 2.0 multicard reader
Bus 003 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 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub

Try running 'lspci -v'

00:1d.0 USB Controller: Intel Corporation 82801DB/DBL/DBM (ICH4/ICH4-L/ICH4-M) USB UHCI Controller #1 (rev 02) (prog-if 00 [UHCI])
        Subsystem: ASUSTeK Computer Inc. P4B533
        Flags: bus master, medium devsel, latency 0, IRQ 16
        I/O ports at b800 [size=32]
        Kernel driver in use: uhci_hcd
        Kernel modules: uhci-hcd

00:1d.1 USB Controller: Intel Corporation 82801DB/DBL/DBM (ICH4/ICH4-L/ICH4-M) USB UHCI Controller #2 (rev 02) (prog-if 00 [UHCI])
        Subsystem: ASUSTeK Computer Inc. P4B533
        Flags: bus master, medium devsel, latency 0, IRQ 19
        I/O ports at b400 [size=32]
        Kernel driver in use: uhci_hcd
        Kernel modules: uhci-hcd

00:1d.2 USB Controller: Intel Corporation 82801DB/DBL/DBM (ICH4/ICH4-L/ICH4-M) USB UHCI Controller #3 (rev 02) (prog-if 00 [UHCI])
        Subsystem: ASUSTeK Computer Inc. P4B533
        Flags: bus master, medium devsel, latency 0, IRQ 18
        I/O ports at b000 [size=32]
        Kernel driver in use: uhci_hcd
        Kernel modules: uhci-hcd

00:1d.7 USB Controller: Intel Corporation 82801DB/DBM (ICH4/ICH4-M) USB2 EHCI Controller (rev 02) (prog-if 20 [EHCI])
        Subsystem: ASUSTeK Computer Inc. P4B533
        Flags: bus master, medium devsel, latency 0, IRQ 23
        Memory at ce800000 (32-bit, non-prefetchable) [size=1K]
        Capabilities: <access denied>
        Kernel driver in use: ehci_hcd
        Kernel modules: ehci-hcd

PythonEater

Member

From: Kentucky, USA

Registered: 2010-08-19

Posts: 34

Re: USB Read/Write Speed is Incredibly Slow

The device is indeed the HP one.
I've tried all the usb ports, and I get the same speed. All the ports should support usb 2; I've never had a problem with them before.

lspci -v

00:02.0 USB Controller: nVidia Corporation MCP78S [GeForce 8200] OHCI USB 1.1 Controller (rev a1) (prog-if 10 [OHCI])
    Subsystem: Hewlett-Packard Company Device 360a
    Flags: bus master, 66MHz, fast devsel, latency 0, IRQ 17
    Memory at c0006000 (32-bit, non-prefetchable) [size=4K]
    Capabilities: [44] Power Management version 2
    Kernel driver in use: ohci_hcd

00:02.1 USB Controller: nVidia Corporation MCP78S [GeForce 8200] EHCI USB 2.0 Controller (rev a1) (prog-if 20 [EHCI])
    Subsystem: Hewlett-Packard Company Device 360a
    Flags: bus master, 66MHz, fast devsel, latency 0, IRQ 17
    Memory at c0007000 (32-bit, non-prefetchable) [size=256]
    Capabilities: [44] Debug port: BAR=1 offset=00a0
    Capabilities: [80] Power Management version 2
    Kernel driver in use: ehci_hcd

00:04.0 USB Controller: nVidia Corporation MCP78S [GeForce 8200] OHCI USB 1.1 Controller (rev a1) (prog-if 10 [OHCI])
    Subsystem: Hewlett-Packard Company Device 360a
    Flags: bus master, 66MHz, fast devsel, latency 0, IRQ 16
    Memory at c0008000 (32-bit, non-prefetchable) [size=4K]
    Capabilities: [44] Power Management version 2
    Kernel driver in use: ohci_hcd

00:04.1 USB Controller: nVidia Corporation MCP78S [GeForce 8200] EHCI USB 2.0 Controller (rev a1) (prog-if 20 [EHCI])
    Subsystem: Hewlett-Packard Company Device 360a
    Flags: bus master, 66MHz, fast devsel, latency 0, IRQ 16
    Memory at c0007400 (32-bit, non-prefetchable) [size=256]
    Capabilities: [44] Debug port: BAR=1 offset=00a0
    Capabilities: [80] Power Management version 2
    Kernel driver in use: ehci_hcd

---

"You can just deny pain… until infection leads to amputation. Then it’s really gone."
    --Craig Benzine

ewaller

Administrator

From: Pasadena, CA

Registered: 2009-07-13

Posts: 20,177

Re: USB Read/Write Speed is Incredibly Slow

Are you using a cable or does the device connect directly?
If you've a cable, How long is it?
Have you tried a shorter or higher quality cable?

If the impedance is wrong or if there is significant group delay on the cable, the device bus negotiation may be picking the lower speed.

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PythonEater

Member

From: Kentucky, USA

Registered: 2010-08-19

Posts: 34

Re: USB Read/Write Speed is Incredibly Slow

Unfortunately, the device is plugged directly into the port. No other devices are attached via usb besides a mouse.

---

"You can just deny pain… until infection leads to amputation. Then it’s really gone."
    --Craig Benzine

sirocco

Member

Registered: 2008-03-10

Posts: 149

Re: USB Read/Write Speed is Incredibly Slow

del.

Last edited by sirocco (2011-04-15 04:38:09)

premier

Member

Registered: 2006-12-07

Posts: 16

Re: USB Read/Write Speed is Incredibly Slow

The ehci_hcd module is getting loaded so it looks to be an issue with the driver for nVidia Corporation MCP78S usb controller.

You can try modifying some of the USB BIOS settings to see if that has any affect.  Could be a BIOS-kernel interaction, suspend, or power management issue.

Some google search returned some issues with that USB controller but they don't look like the problem your having.

https://bugs.launchpad.net/ubuntu/+sour … bug/455660
http://www.nvnews.net/vbulletin/archive … 35022.html

Enabling more USB debug may help troubleshoot

http://www.linux-usb.org/FAQ.html#ts7

PythonEater

Member

From: Kentucky, USA

Registered: 2010-08-19

Posts: 34

Re: USB Read/Write Speed is Incredibly Slow

Unfortunately, the CMOS settings on this computer are probably the most limited settings I have ever seen. All I can do is turn the fan "Always On" or "Always Off", and change the boot order. So that's out. I keep going back to the fact that it works flawlessly on older kernel releases. I'll file a bug report over on kernel.org and see how that goes.

---

"You can just deny pain… until infection leads to amputation. Then it’s really gone."
    --Craig Benzine

king.flasher.dave

Member

From: Berlin

Registered: 2008-11-25

Posts: 140

Website

Re: USB Read/Write Speed is Incredibly Slow

I'll be happy to vote for that bug. Experiencing the same issues with ntfs partitions on usb pen drives (not usb harddrives though) sometimes.
It's a really annoying issue and I've never found a downright straight answer for why it's happening

I'm on gnome and latest kernel (2.6.38). This problem has been around for me for much longer than 2.6.37 though.

lspci:

00:00.0 Host bridge: nVidia Corporation MCP79 Host Bridge (rev b1)
00:00.1 RAM memory: nVidia Corporation MCP79 Memory Controller (rev b1)
00:03.0 ISA bridge: nVidia Corporation MCP79 LPC Bridge (rev b2)
00:03.1 RAM memory: nVidia Corporation MCP79 Memory Controller (rev b1)
00:03.2 SMBus: nVidia Corporation MCP79 SMBus (rev b1)
00:03.3 RAM memory: nVidia Corporation MCP79 Memory Controller (rev b1)
00:03.5 Co-processor: nVidia Corporation MCP79 Co-processor (rev b1)
00:04.0 USB Controller: nVidia Corporation MCP79 OHCI USB 1.1 Controller (rev b1)
00:04.1 USB Controller: nVidia Corporation MCP79 EHCI USB 2.0 Controller (rev b1)
00:06.0 USB Controller: nVidia Corporation MCP79 OHCI USB 1.1 Controller (rev b1)
00:06.1 USB Controller: nVidia Corporation MCP79 EHCI USB 2.0 Controller (rev b1)
00:08.0 Audio device: nVidia Corporation MCP79 High Definition Audio (rev b1)
00:09.0 PCI bridge: nVidia Corporation MCP79 PCI Bridge (rev b1)
00:0a.0 Ethernet controller: nVidia Corporation MCP79 Ethernet (rev b1)
00:0b.0 SATA controller: nVidia Corporation MCP79 AHCI Controller (rev b1)
00:0c.0 PCI bridge: nVidia Corporation MCP79 PCI Express Bridge (rev b1)
00:10.0 PCI bridge: nVidia Corporation MCP79 PCI Express Bridge (rev b1)
00:15.0 PCI bridge: nVidia Corporation MCP79 PCI Express Bridge (rev b1)
00:16.0 PCI bridge: nVidia Corporation MCP79 PCI Express Bridge (rev b1)
00:17.0 PCI bridge: nVidia Corporation MCP79 PCI Express Bridge (rev b1)
00:18.0 PCI bridge: nVidia Corporation MCP79 PCI Express Bridge (rev b1)
01:07.0 FireWire (IEEE 1394): Ricoh Co Ltd R5C832 IEEE 1394 Controller (rev 05)
01:07.1 SD Host controller: Ricoh Co Ltd R5C822 SD/SDIO/MMC/MS/MSPro Host Adapter (rev 22)
01:07.2 System peripheral: Ricoh Co Ltd R5C592 Memory Stick Bus Host Adapter (rev 12)
01:07.3 System peripheral: Ricoh Co Ltd xD-Picture Card Controller (rev 12)
02:00.0 VGA compatible controller: nVidia Corporation G98 [GeForce 9200M GS] (rev a1)
03:00.0 VGA compatible controller: nVidia Corporation C79 [GeForce 9400M G] (rev b1)
06:00.0 Network controller: Atheros Communications Inc. AR928X Wireless Network Adapter (PCI-Express) (rev 01)

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premier

Member

Registered: 2006-12-07

Posts: 16

Re: USB Read/Write Speed is Incredibly Slow

Throughput issues with Flash devices can occur for many reasons (which USB pen drives always are nowadays).  In this case, the 1 MB/sec max throughput points to a specific problem with USB high speed.  More details are needed from the USB EHCI driver to troubleshoot this issue further.   

When EHCI doesn't work, then USB should fall back to full speed (OHCI or UHCI).  If you have a high speed usb controller (most modern computers have this) and a high speed device, but the 'lsusb' command shows that it is being handled by non high speed root hub then something is wrong.

PythonEater

Member

From: Kentucky, USA

Registered: 2010-08-19

Posts: 34

Re: USB Read/Write Speed is Incredibly Slow

Useful info to include in the bug report. Thanks premier.

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"You can just deny pain… until infection leads to amputation. Then it’s really gone."
    --Craig Benzine