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

[pete smout]

On 05/05/13 13:17, Basil Chupin wrote:
> On 05/05/13 20:10, Jkhatri wrote:
>> On Sunday 05 May 2013 03:31 PM, Colin Law wrote:
>>> 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
>>>>
>>>>
>>>> why like that ???
>>>>
>>>> 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
>>>>
>> Thanks for your quick reply, colin
>>
>> but same drive works fine with M$ windows, on same PC ( dual boot ).
>> it copies same file quickly, and I'm able to eject it as soon as copy
>> process completed. But it takes long time in Ubuntu it takes dual
>> time, like  copy time + safely remove message progress bar time
>>
>> both windows and Ubuntu are 64bit version and installed on same laptop
>> ( dual boot )
>>
>> Thanks
>
> You get fast copying in M$ because the stick is formatted in msdos.
>
> Writing from Linux to a msdos formatted drive, such as your USB stick,
> takes "for ever". There is a very complicated explanation for this but
> believe me it is true (something to do with the kernel).

<Snip>

Hi,

I know nothing of the complicated kernel reasons, but I can back this up 
through personal experience!
I have an external HDD formatted to 'EXT4' for backing up important 
files from my '*buntu' box and a 16gb flash stick for moving files 
around to other systems which is formatted to 'VFAT'.

Copying the same file (my CV) to the stick takes a whole 10 sec longer 
than to my ext HDD, this is only a text file so I would imagine that 
larger files (videos etc) would see this difference increase!

I am not surprised by this as UNIX file systems carry more info 
(permissions, groups, owners etc.) than is available on VFAT, and I'm 
guessing here that some complicated algorithms are needed to process 
this additional info.

Please feel free to correct me if any of my assumptions are wrong!

Regards

Pete