2006-09-20 18:58:31

by CIJOML

Subject: Very slow write on flash drive in sync mode???

Hi,

I use SanDisk cruzer Titanium 2 GB mounted as sync in fstab

usb 4-2: new high speed USB device using ehci_hcd and address 5
usb 4-2: configuration #1 chosen from 1 choice
scsi1 : SCSI emulation for USB Mass Storage devices
usb-storage: device found at 5
usb-storage: waiting for device to settle before scanning
Vendor: SanDisk Model: U3 Titanium Rev: 2.16
Type: Direct-Access ANSI SCSI revision: 02
SCSI device sda: 4001425 512-byte hdwr sectors (2049 MB)
sda: Write Protect is off
sda: Mode Sense: 03 00 00 00
sda: assuming drive cache: write through
SCSI device sda: 4001425 512-byte hdwr sectors (2049 MB)
sda: Write Protect is off
sda: Mode Sense: 03 00 00 00
sda: assuming drive cache: write through
sda: sda1
sd 1:0:0:0: Attached scsi removable disk sda
sd 1:0:0:0: Attached scsi generic sg0 type 0
Vendor: SanDisk Model: U3 Titanium Rev: 2.16
Type: CD-ROM ANSI SCSI revision: 02
sr0: scsi3-mmc drive: 8x/40x writer xa/form2 cdda tray
sr 1:0:0:1: Attached scsi CD-ROM sr0
sr 1:0:0:1: Attached scsi generic sg1 type 5
usb-storage: device scan complete

/dev/sda1 /mnt/cruzer_sync vfat user,noauto,sync
0 0
/dev/sda1 /mnt/cruzer auto user,noauto 0 0


When I use flash drive in sync mode, it writes on it only 64kB/s. When I
umount it and mount it in not sync mode but do sync manually after it writes
into memory, kernel writes on flash drive 11 MB/s!!! What is wrong in my
configuration?

Kernel 2.6.18, Debian testing

Thanks for help

Michal

2006-09-20 19:13:51

by Tomasz Torcz

Subject: Re: Very slow write on flash drive in sync mode???

On Wed, Sep 20, 2006 at 08:58:05PM +0200, CIJOML wrote:
> Hi,
>
> I use SanDisk cruzer Titanium 2 GB mounted as sync in fstab
> /dev/sda1 /mnt/cruzer_sync vfat user,noauto,sync
>
> When I use flash drive in sync mode, it writes on it only 64kB/s. When I
> umount it and mount it in not sync mode but do sync manually after it writes
> into memory, kernel writes on flash drive 11 MB/s!!! What is wrong in my
> configuration?

That's expected with sync vfat mount. Use other filesystem or async.

--
Tomasz Torcz "Funeral in the morning, IDE hacking
[email protected] in the afternoon and evening." - Alan Cox