FC5: High system load when copying data to slow USB media

[Boris Glawe]

Hi,

I have a problem with my 2GB Memory Stick Pro Duo Card. The card itself 
is an orginal MemoryStick PRO Duo from Sony.

I am using this card in my cell phone. The phone is a Sony Ericsson 
W810i, which is capable to appear as an usb mass storage device. I also 
have an USB 2.0 card reader. The problem described below happens with 
both the card reader and the cell phone.

My problem is, that copying large amounts of data (a few hundred MBs, 
for example) to that device causes the system load to increase to almost 
100% and, under certain circumstances, to lock my desktop from time to 
time during the copying process. It is normal that copying takes very 
long, as the card itself is very slow in writing, but the high system 
load in combination with the lack of responsiveness of the whole system 
seems to be a bug!?

In addition to this problem, copying data to such a device is very opaque:
A copy command on either the terminal or the nautilus gui, immediately 
terminates successfully, though the data has not really been written to 
the card, yet. This asynchronous behaviour is ok for performance issues, 
but one doesn't know when the card can be unmountet. I actually know 
what to do: I run the command sync and as soon as this commands 
terminates, I know that the cache is written to the card. Problem with 
this: When sync executes, the system load increases even more and the 
desktop is much more often locked, then it would be without having 
executed the sync command. The system stabilizes, as soon as the cache 
is written to the card.

Unounting the card with the Gnome gui make things even stranger. Gnome 
obviously seems to unmount the card though the cache has not been 
written yet (the symbol disappears from the desktop), but comes back 
after about 30-60 seconds with an error message, that the card cannot be 
unmountet (One usually uses this time to remove the card from the 
reader) This unmount command triggers a sync, of course, which again 
results in the same behaviour as described in the paragraph above, when 
running sync manually.
A "df -ah" on the terminal results in a "/media/disk not found" message, 
then.
This is one of the reasons why it would be very nice to at least know, 
when the device can be unmountet.

Can you confirm the problem with the high system load and the lack of 
responsiveness when copying large amount of data to a slow USB mass 
storage device, like my 2GB memory stick pro duo?

Thanks for any hint and comment

greets Boris