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[Bug 1582759] Re: Unexpected low write rate with Lexar JumpDrive P20 64GB flash drives


This issue appears to be an upstream bug, since you tested the latest
upstream kernel. Would it be possible for you to open an upstream bug
report[0]? That will allow the upstream Developers to examine the issue,
and may provide a quicker resolution to the bug.

Please follow the instructions on the wiki page[0]. The first step is to
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bug may be opened on bugzilla.kernel.org.

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[0] https://wiki.ubuntu.com/Bugs/Upstream/kernel

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  Unexpected low write rate with Lexar JumpDrive P20 64GB flash drives

Status in linux package in Ubuntu:

Bug description:
  We are hitting an unexpected low write rate with Lexar JumpDrive P20
  64GB flash drives connected via USB 3.0 on multiple machines and
  across multiple kernels (3.13, 4.4). Expected is a write rate of 270
  MB/s and we only get 45 MB/s. Under Mac OS X and Windows we get the
  expected write rate of 270 MB/s. The read rate is as expected at 400
  MB/s on all operating systems.

  Lexar JumpDrive P20 details:

  Tested machines:
  * HP Z440
  * Lenovo ThinkPad X250

  Tested kernels:
  * 3.13 (Trusty)
  * 4.4 (Xenial)

  lsusb details:

  $ lsusb -t
  /:  Bus 03.Port 1: Dev 1, Class=root_hub, Driver=xhci_hcd/4p, 5000M
      |__ Port 2: Dev 2, If 0, Class=Mass Storage, Driver=usb-storage, 5000M  <-- USB 3.0
  /:  Bus 02.Port 1: Dev 1, Class=root_hub, Driver=xhci_hcd/11p, 480M
      |__ Port 1: Dev 2, If 0, Class=Vendor Specific Class, Driver=, 12M
      |__ Port 8: Dev 4, If 0, Class=Video, Driver=uvcvideo, 480M
      |__ Port 8: Dev 4, If 1, Class=Video, Driver=uvcvideo, 480M
  /:  Bus 01.Port 1: Dev 1, Class=root_hub, Driver=ehci-pci/3p, 480M
      |__ Port 1: Dev 2, If 0, Class=Hub, Driver=hub/8p, 480M

  $ sudo lsusb -d 05dc:a212 -vvv

  Bus 003 Device 002: ID 05dc:a212 Lexar Media, Inc. 
  Device Descriptor:
    bLength                18
    bDescriptorType         1
    bcdUSB               3.00
    bDeviceClass            0 (Defined at Interface level)
    bDeviceSubClass         0 
    bDeviceProtocol         0 
    bMaxPacketSize0         9
    idVendor           0x05dc Lexar Media, Inc.
    idProduct          0xa212 
    bcdDevice            1.00
    iManufacturer           1 Lexar
    iProduct                2 USB Flash Drive
    iSerial                 3 0C5E8B182D1D474C
    bNumConfigurations      1
    Configuration Descriptor:
      bLength                 9
      bDescriptorType         2
      wTotalLength           44
      bNumInterfaces          1
      bConfigurationValue     1
      iConfiguration          0 
      bmAttributes         0x80
        (Bus Powered)
      MaxPower              224mA
      Interface Descriptor:
        bLength                 9
        bDescriptorType         4
        bInterfaceNumber        0
        bAlternateSetting       0
        bNumEndpoints           2
        bInterfaceClass         8 Mass Storage
        bInterfaceSubClass      6 SCSI
        bInterfaceProtocol     80 Bulk-Only
        iInterface              0 
        Endpoint Descriptor:
          bLength                 7
          bDescriptorType         5
          bEndpointAddress     0x81  EP 1 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     0x02  EP 2 OUT
          bmAttributes            2
            Transfer Type            Bulk
            Synch Type               None
            Usage Type               Data
          wMaxPacketSize     0x0400  1x 1024 bytes
          bInterval               0
          bMaxBurst               3
  Binary Object Store Descriptor:
    bLength                 5
    bDescriptorType        15
    wTotalLength           22
    bNumDeviceCaps          2
    USB 2.0 Extension Device Capability:
      bLength                 7
      bDescriptorType        16
      bDevCapabilityType      2
      bmAttributes   0x00000006
        Link Power Management (LPM) Supported
    SuperSpeed USB Device Capability:
      bLength                10
      bDescriptorType        16
      bDevCapabilityType      3
      bmAttributes         0x00
      wSpeedsSupported   0x000e
        Device can operate at Full Speed (12Mbps)
        Device can operate at High Speed (480Mbps)
        Device can operate at SuperSpeed (5Gbps)
      bFunctionalitySupport   2
        Lowest fully-functional device speed is High Speed (480Mbps)
      bU1DevExitLat          10 micro seconds
      bU2DevExitLat        2047 micro seconds
  Device Status:     0x000c
    (Bus Powered)
    U1 Enabled
    U2 Enabled

  Write speed with kernel 4.4:

  $ sudo dd if=/dev/zero of=/dev/sdb bs=1M count=256
  256+0 records in
  256+0 records out
  268435456 bytes (268 MB) copied, 5.98705 s, 44.8 MB/s

  Write speed under Mac OS X:

  $ sudo dd if=/dev/zero of=/dev/rdisk2 bs=1048576 count=256
  256+0 records in
  256+0 records out
  268435456 bytes transferred in 0.941998 secs (284963933 bytes/sec)
  ApportVersion: 2.20.1-0ubuntu2
  Architecture: amd64
   /dev/snd/controlC0:  test       1249 F.... pulseaudio
   /dev/snd/controlC1:  test       1249 F.... pulseaudio
  CurrentDesktop: Unity
  DistroRelease: Ubuntu 16.04
  HibernationDevice: RESUME=UUID=78c6220a-1695-4cce-bea4-54c32e2568ed
  InstallationDate: Installed on 2016-05-18 (0 days ago)
  InstallationMedia: Ubuntu 16.04 LTS "Xenial Xerus" - Release amd64 (20160420.1)
  MachineType: Hewlett-Packard HP EliteBook 840 G1
  Package: linux (not installed)
  ProcFB: 0 inteldrmfb
  ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-4.4.0-22-generic root=UUID=81dd7ff9-ab0b-42f5-87f4-10ebb94e99f6 ro quiet splash vt.handoff=7
  ProcVersionSignature: Ubuntu 4.4.0-22.40-generic 4.4.8
   linux-restricted-modules-4.4.0-22-generic N/A
   linux-backports-modules-4.4.0-22-generic  N/A
   linux-firmware                            1.157
  Tags:  xenial
  Uname: Linux 4.4.0-22-generic x86_64
  UpgradeStatus: No upgrade log present (probably fresh install)
  UserGroups: adm cdrom dip lpadmin plugdev sambashare sudo
  _MarkForUpload: True
  dmi.bios.date: 03/25/2014
  dmi.bios.vendor: Hewlett-Packard
  dmi.bios.version: L71 Ver. 01.10
  dmi.board.name: 198F
  dmi.board.vendor: Hewlett-Packard
  dmi.board.version: KBC Version 15.54
  dmi.chassis.asset.tag: 1300144
  dmi.chassis.type: 10
  dmi.chassis.vendor: Hewlett-Packard
  dmi.modalias: dmi:bvnHewlett-Packard:bvrL71Ver.01.10:bd03/25/2014:svnHewlett-Packard:pnHPEliteBook840G1:pvrA3008CD10003:rvnHewlett-Packard:rn198F:rvrKBCVersion15.54:cvnHewlett-Packard:ct10:cvr:
  dmi.product.name: HP EliteBook 840 G1
  dmi.product.version: A3008CD10003
  dmi.sys.vendor: Hewlett-Packard

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