Hi,
I have an external USB ext3 disk drive. Everything is working fine, I plug it in an an icon appears on my (KDE) desktop, which I can use to mount and unmount the device.
However, I have noticed that writing to the device the behaviour is rather different to my main system disks. It appears not much caching is going on - On the main system when creating a large file, the writes a done in big bulks every now and then, whereas on this disk it is continuous low level activity.
I'm wondering if this is normal for a USB disk, or are there options I can teak somewhere to get better mounting ?
jonesc@localhost ~ > mount /dev/hda7 on / type ext3 (rw) proc on /proc type proc (rw) sysfs on /sys type sysfs (rw) devpts on /dev/pts type devpts (rw,gid=5,mode=620) /dev/hda5 on /boot type ext3 (rw) /dev/hda10 on /data type ext3 (rw) /dev/hda6 on /data2 type ext3 (rw) tmpfs on /dev/shm type tmpfs (rw) /dev/hda8 on /home type ext3 (rw) /dev/hda2 on /winxp type ntfs (ro,noexec,nosuid,nodev,umask=000) none on /proc/sys/fs/binfmt_misc type binfmt_misc (rw) sunrpc on /var/lib/nfs/rpc_pipefs type rpc_pipefs (rw) AFS on /afs type afs (rw) /dev/sda1 on /media/MassStorage type ext3 (rw,noexec,nosuid,nodev,sync,data=ordered)
The last one is the USB disk, mounted via HAL. Is this optimal ?
cheers Chris
Chris Jones wrote:
Hi,
I have an external USB ext3 disk drive. Everything is working fine, I plug it in an an icon appears on my (KDE) desktop, which I can use to mount and unmount the device.
However, I have noticed that writing to the device the behaviour is rather different to my main system disks. It appears not much caching is going on - On the main system when creating a large file, the writes a done in big bulks every now and then, whereas on this disk it is continuous low level activity.
I'm wondering if this is normal for a USB disk, or are there options I can teak somewhere to get better mounting ?
By default, USB hard drives are mounted using the sync option. This turns off write caching when writing to the drive. I believe that this is done to limit data loss in case the drive gets unplugged. The delay whey you go to unmount the drive without this option can be long enough that people think there is a problem, and do not wait long enough before unplugging the drive.
If you normally have the drive connected, you can create a ftab entry for the drive and use your own options. You could also write a special HAL rule for this drive.
Mikkel
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Chris Jones -
Mikkel