Update:

In one of my previous post, I've said that I've not reached the USB transfer speed (is 23MB/s to copy a 700MB file located on a SFS partition, into RAM:).

I've supposed that was my code and I've tried to profile it.
After analysing profile data, I've not found major issues in my code that could increase more than 1 or 2 % the speed.

But yesterday I've found that I've forget to setup an important bus parameter: the GapCount.
I'm not going to enter in technical explanations about this value, but just saying that the default value is the max, so the bus is in the most secure mode to handle data.

Most secure = less speed rate.

By descreasing this value to a suitable one using manual operations, I've finally reached a 30MB/s speed using default Ambient copy and even 36MB/s (!!!) by tweaking it using the copy shell command and 1MB per SCSI cmd.

Now I need to make this value setup more automatic.

[ Edited by Yomgui on 2010/10/15 11:32 ]