Arch Linux

Andromea

Member

Registered: 2005-03-19

Posts: 25

USB Speed

When I transfer files over USB to my mp3 player the speed is very unstable, sometimes even stopping.
Is this normal behaviour?

The reason I ask is that when I delete a mp3 on the player and copy another to it, the new and old mp3 get mixed up. I hear parts of the old mp3 in between the one new one.
It's like my computer stops sending but the mp3 player doesn't stop writing (but with nothing to write).

lanrat

Member

From: Poland

Registered: 2003-10-28

Posts: 1,274

Re: USB Speed

One reason that comes to my mind is an usb extension cable. If you're using one of course. Does dmesg show any erros during transfers ?

Another reason might be a second usb 1.1 device connected to the same usb hub.

kth5

Member

Registered: 2004-04-29

Posts: 657

Website

Re: USB Speed

linux is caching write transfers to storage devices to cut down on time needed to complete a transfer user wise. it will only flush the cache when the cache is full, the computer is unused to some extend or the drive is unmounted, as i understood if.

in any case, deleting a file is not an operation that is being cached so this is a real problem. run fsck on that mp3 player of yours or start the fs from scratch. it might be corrupted.
oh, never hot-unplug a usb-storage device before unmounting the fs on it, never ever!

---

I recognize that while theory and practice are, in theory, the same, they are, in practice, different. -Mark Mitchell

Andromea

Member

Registered: 2005-03-19

Posts: 25

Re: USB Speed

dmesg shows no errors while transferring. This is what dmesg shows on attaching and mounting:

usb 1-2: new full speed USB device using ohci_hcd and address 7
scsi5 : SCSI emulation for USB Mass Storage devices
usb-storage: device found at 7
usb-storage: waiting for device to settle before scanning
  Vendor: COWON     Model: iAUDIO 5          Rev: 0100
  Type:   Direct-Access                      ANSI SCSI revision: 04
SCSI device sda: 2032128 512-byte hdwr sectors (1040 MB)
sda: Write Protect is off
sda: Mode Sense: 38 00 00 00
sda: assuming drive cache: write through
SCSI device sda: 2032128 512-byte hdwr sectors (1040 MB)
sda: Write Protect is off
sda: Mode Sense: 38 00 00 00
sda: assuming drive cache: write through
 sda: sda1
sd 5:0:0:0: Attached scsi removable disk sda
usb-storage: device scan complete
UDF-fs: No partition found (1)
Unable to identify CD-ROM format.

What does 'UDF-fs: No partition found' mean? Couldn't find anything useful with google.

I ran fsck on it, this is what it said:

[root@andromea andromea]# fsck /dev/sda1
fsck 1.38 (30-Jun-2005)
dosfsck 2.11, 12 Mar 2005, FAT32, LFN
/RECORDS/..
  Start (2) does not point to .. (0)
Reclaimed 1 unused cluster (4096 bytes).
Free cluster summary wrong (131878 vs. really 131879)
1) Correct
2) Don't correct
? 1
Leaving file system unchanged.
/dev/sda1: 33 files, 121629/253508 clusters

So I choose 1 to correct it, but it's still leaving the filesystem unchanged?

lanrat

Member

From: Poland

Registered: 2003-10-28

Posts: 1,274

Re: USB Speed

Maybe you should delete and reformat this partition.