USB2 Drives

IDE drives connected through a USB2/IDE translator may have problems. I have been using IDE hotswap with a customized 2.4.22 linux kernel. IDE hotswap is no longer in the kernel, so I have been experimenting with USB2 hotswap on a 2.6.18 kernel (Scientific Linux 5, an RHEL5 clone).

My experiment does multiple passes of filling and emptying a 432GB ext3 partition on a 500GB Seagate Barracuda 7200.9 PATA-100 drive. I wrote a little C program to write 100MB files, which sits in a shell script that does this 4300 times, reporting timing.

The computer is a 1.7!GHz P4 with 1GB of RAM, using a no-name-chinese 3 port USB controller with a VIA Technologies VT6202 (date code 0301) USB2 interface chip. An ADS-Tech USBX-2000 USB controller with an NEC D720101GJ chipset appears to be about the same speed.

I tried a bunch of different USB2 to IDE translators. Here are the results, from awful to OK:

0) "Control" - direct IDE connection to Promise !Ultra133TX2

PCI controller with PDC20269 controller (date code 0409). Results: Wrote 430GB at 30.6MB/sec (4 hrs), as fast as it gets.

1) No-name-chinese, USB to IDE smart cable. 2005 swap meet.

Claimed Linux compatability. Genesys GL811E bridge chip . Results: Doesn't even register with "lsusb". Doorstop, probably a defective individual unit.

2) Vantec, USB to IDE smart cable (also SATA). 2007 purch.

JMicron 20337 chip, 0643 date code. Results: Registers with "lsusb" but does not mount, though there may be some data needed in a table somewhere that will fix this. Unlike other devices with an "!Interface" of 0, this device has an value of "6 MSC Bulk-Only Transfer", whatever that means.

3) !SanMax/inClose USB2DOCK swap cage . 2003 Fry's Electronics.

Cypress C768013 chip, 0304 date code. With a 2.4.22 kernel this locked up after an hour or so. 2.6.18 Results: locks up immediately

4) No-name-chinese, USB to IDE smart cable. May 2007 PCCLUB.

Looks like the picture of a SABRENT device at Tiger Direct. Cypress AT2LP Demo RC17 chip according to lsusb -v . Results: Worked for a while, moved 60GB in about an hour (16.7MB/s), then hung and locked up the kernel.

5) ViPower VP-1028LSF swap cage. 2003.03.17 design. 2004 purch.

Genesys GL811USB chip, there are multiple versions Results: Wrote 233GB at 11.0MB/sec (6 hrs), slow.

6) Vantec CB-IUSB20 USB to IDE smart cable, May 2007 Fry's.

Genesys chipset according to lsusb -v. Results: Wrote 430GB at 14.6MB/sec (8 hrs), slow.

7) UltraSum TZ350B2 external enclosure. 2004 Local computer store.

Myson Century CS88136-103 chip, 0410 date code. Bypassed wimpy power supply. Results: Wrote 430GB at 17.0MB/sec (7 hrs), tolerable.

8) ViPower VP-1028LSF swap cage. 2003.07.04 design. 2006 purch.

Cypress C768300A chip 0404, there are multiple versions Results: Wrote 430GB at 19.6MB/sec (6 hrs), tolerable.

As you can see, a random sampling of USB2 drives and enclosures revealed scattered results, from broken to flaky to slow to tolerable. All of the drives are slow, compared to the 48MB/sec one might expect for a 480MB USB2 bus or the 30MB/sec of a direct IDE connection. Perhaps handshaking and such slows USB to IDE connections down a lot.

Feel free to add to this. I am especially interested in USB2 to IDE smart cables, cheap/fast/good .

RussellSenior's working device (afaict)

I haven't run your test, but I've been using an ADS Technologies USB2 to IDE external enclosure without apparent errors. ID [=06e1:d185]

 Bus 005 Device 002: ID 06e1:d185 ADS Technologies, Inc.
 Device Descriptor:
  bLength                18
  bDescriptorType         1
  bcdUSB               2.00
  bDeviceClass            0 (Defined at Interface level)
  bDeviceSubClass         0 
  bDeviceProtocol         0 
  bMaxPacketSize0        64
  idVendor           0x06e1 ADS Technologies, Inc.
  idProduct          0xd185 
  bcdDevice            0.01
  iManufacturer          56 
  iProduct               78 
  iSerial               100 
  bNumConfigurations      1
  Configuration Descriptor:
    bLength                 9
    bDescriptorType         2
    wTotalLength           32
    bNumInterfaces          1
    bConfigurationValue     1
    iConfiguration          0 
    bmAttributes         0xc0
      Self Powered
    MaxPower                0mA
    Interface Descriptor:
      bLength                 9
      bDescriptorType         4
      bInterfaceNumber        0
      bAlternateSetting       0
      bNumEndpoints           2
      bInterfaceClass         8 Mass Storage
      bInterfaceSubClass      6 SCSI
      bInterfaceProtocol     80 Bulk (Zip)
      iInterface              0 
      Endpoint Descriptor:
        bLength                 7
        bDescriptorType         5
        bEndpointAddress     0x02  EP 2 OUT
        bmAttributes            2
          Transfer Type            Bulk
          Synch Type               None
          Usage Type               Data
        wMaxPacketSize     0x0200  1x 512 bytes
        bInterval               0
      Endpoint Descriptor:
        bLength                 7
        bDescriptorType         5
        bEndpointAddress     0x88  EP 8 IN
        bmAttributes            2
          Transfer Type            Bulk
          Synch Type               None
          Usage Type               Data
        wMaxPacketSize     0x0200  1x 512 bytes
        bInterval               0