RE: USB Devices not working
From: Fritz Whittington [mailto:f.whittington@att.net]
Sent: Sunday, February 01, 2004 10:46 AM
>> Also, once you are have troubleshooted your issue, always manually
>> unmount
>> your device before unplugging it, especially if you are
performing write
>> operations to it.
>>
How very important! If you don't believe that delayed-write is
working, try mounting a USB fs (one that uses a solid-state
memory, like
Compact Flash or Smart Media), copying several MB of files
from it to a
hdd, and note how slow it is. Then delete all the files on the USB
device, and copy all the files back. The copy is done almost in an
instant! But then, when you unmount it, you can see it take several
seconds to actually write the files from cache. So if you
yanked it out
without unmounting it, you wouldn't really have anything.
It would be nice if usb devices such as this could be forced to write their
data ASAP instead of waiting for a umount (despite a performance lag). It
is so tempting for many people that I know to just go ahead and unplug. I
am going to do some research on this.