Re: Transfer Speed Problem with IN Bulk Transfers at Certain Computers

[Xiaofan C. <xia...@gm...>]

On Sat, Jan 12, 2013 at 2:12 AM, jakubon2 <ond...@ns...> wrote:
> Definitely, the problem appears at one of the tablets we use with USB 2.0
> (not 3.0), it's Durabook t7m ( http://www.durabook.com/en/product.php?no=62#
> <http://www.durabook.com/en/product.php?no=62#>  ). But, when we try to copy
> from a flash, the speed reaches 20MBps or more easily.

I see. That is an Atom and it does point to a lower performance system here.

Another guess, have you profiled your application in the failed
system? Specifically I am thinking the file dumping process
may be slow and may block your 2nd thread.

> the second thread:
> -waiting on conditional variable from the first thread
> -if signalled, the counter of the received packets is compared to the
> counter of the packets dumped to the file
> -the remaining packets are dumped to the file

What if you disable the above two dumping process?
Or you reduce the number of file dumping by doing it
differently (less file dumping)? Again I am just guessing
here since your Atom computer has an 1.8inch HDD.

> -the count of the written packets is incremented
> -the thread loops back to the conditional variable

-- 
Xiaofan