writing data to disk message... when safely remove USB drive

[Colin Law]

On 5 May 2013 10:54, Jkhatri <khatri.jatin at gmail.com> wrote:
> Dear ALL
>
> I'm facing one strange issue, whenever I copy some data to USB thumb drive (
> some big files, say 2GB .avi or something) its displays progress bar on
> screen that data is being copied to disk and finally it finished but strange
> this starts when I safely remove that USB drive, a safely remove drive
> window opens with message " writing data to disk " and it takes long time.
> If I remove device before that message goes, nothing is written to disk
> ..!!!!!
>
> so it means no data is copied when I use Ctrl+c and Ctrl+v to thumb drive,
> but data start copying when I safely remove USB drive.
>
> why like that ???

Because of the way data is written to flash memory the copy can appear
to finish before the writing to flash is complete.  The stick contains
internal buffers that can be written to quickly, but you must keep the
power on till it has finished writing it to flash.  If you leave it
several minutes after the copy before attempting to eject you should
find it then ejects immediately (as the write is complete).  If it
becomes very slow on a particular stick that probably means that it is
failing as it takes longer to write as the flash wears out.

Colin