Windows 7 64-bit unresponsive during nowind data transfers

[GoogleCodeExporter]

What steps will reproduce the problem?
1. nwhostapp -i <disk> on   Windows 7 64-bit 
2. run any game 
3.

When transfers are in progress, windows seems to become unresponsive for 
periods of time (sometimes a few seconds), alt-tab or clicks in other windows 
have no effect. 

When the tranfer is done, all seems normal.
Part of the problem might be 'heavy' retry traffic.
If this is a timing problem and blocks start failing, retries occur, and
they can also fails, snowballing the problem.

Original issue reported on code.google.com by janwilm...@gmail.com on 6 Nov 2011 at 10:48

[GoogleCodeExporter]

This has also been seen during flashing, which will cause flashing to fail 
since it has no error correction. It can however be worked around easely, by 
just flashing again.
(restarting the nwhostapp -f nowind.rom command while still in the red-screen 
will work as many times as needed.

Original comment by janwilm...@gmail.com on 7 Nov 2011 at 9:01

[GoogleCodeExporter]

Windows 7 crashes, without any messages, just a black screen and heavy CPU 
usage (noticeable by the spinning up of the fan) occurs. It seems to be 
reproducible regularly when when both heavy Ethernet + heavy USB traffic 
occurs. It appears to be a USB or Ethernet driver problem. I have only one PC 
on which this happens.

Original comment by janwilm...@gmail.com on 26 Jan 2012 at 9:19

[GoogleCodeExporter]

This issue has been seen only on certain USB3.0 ports and only on windows 7, 
for now, we will call it an USB hardware quirk, not anything we can fix. A 
workaround is to just plug nowind into another non-USB 3.0 port.

Original comment by janwilm...@gmail.com on 30 Jan 2013 at 2:53

• Changed state: Done

[GoogleCodeExporter]

The controller that has this problem is a "NEC Electronics USB 3.0 Host 
controller" on a HP8740w laptop using a Driver version 1.0.18.0 dated 20-11-2009

Driver Node Strong Name: 
oem22.inf:NECEL.NTamd64:NUSB3XHC:1.0.18.0:pci\ven_1033&dev_0194

Original comment by janwilm...@gmail.com on 30 Jan 2013 at 3:09

[GoogleCodeExporter]

Just opening the device and setting FT_SetLatencyTimer = 1 seems to cause 
massive CPU load (+50% in the 'System' process) when the FT245 is connected to 
the USB3.0 port. FT_SetLatencyTimer = 16 (the default) still causes 3-4%, it 
looks like either a USB hardware specific issue, a USB kernel driver issue or a 
FT245r+USB3.0 issue.

Original comment by janwilm...@gmail.com on 30 Jan 2013 at 4:09