Re: Preventing delayed USB writes

[pedxing <pedxing@gmail.com>]

On May 18, 12:30 pm, pedxing <pedx...@gmail.com> wrote:
> On May 17, 11:00 pm, Douglas Allan Tutty <dtu...@porchlight.ca> wrote:
>
>
>
> > On Tue, May 15, 2007 at 10:55:18PM -0600, Paul E Condon wrote:
> > > > On 05/15/07 20:37, H.S. wrote:
> > > > > pedxing wrote:
>
> > > > >> When I write to a USB device (stick or mp3 player), I notice that
> > > > >> the writes appear to happen quickly, but actually take a long time to
> > > > >> complete.  I assume there is some form of caching going on.
>
> > > > >> To be safe, I issue a sync command from a terminal and wait for it
> > > > >> (up to 15 minutes!) to complete before unmounting the drive.
>
[snip]
>
> > fstab, noatime
>
> I am going to give sync,noatime in fstab a try, using a scratch stick.
>
> It definitely makes KDE behave correctly: it gives you a more accurate
> transfer rate (true 1MB/sec vs. the untrue 6-7MB/sec), when it says
> finished copying, it is finished copying and the safely remove works
> every time.
[snip]

I guess I spoke too soon.  With some devices (iRiver, Hama 2GB stick)
this works fine, but with my wife's mp3 player (DNT 4GB flash), the
noatime causes a problem that prevents writing (konqueror says "can't
copy" cp says "I/O error").  I don't think I want to use the sync
option without noatime.

So, back to using konq to copy and running sync from a terminal to
know when the copy is truly finished.

Thanks for all of the suggestions regarding how to manage removable
storage in the main DE's, but I already knew about them.

Just for clarification, the problem is that right after using
konqueror to copy a lot of files to a USB device, the media manager's
"safely remove" option times out and gives an error message (ps dump)
when trying to unmount.  Eventually the sync completes, but the user
doesn't get any indication that it's waiting for the sync, or how long
the sync is expected to take.

Oh, well, yet another Linux annoyance.

One nice thing about Linux annoyances, at least there is some kind of
workaround...

-Ped