I have a problem with inadequate throughput when submitting bulk urbs with transfer buffers greater than about 128kB. ...
The system looks like this: kernel 2.6.0 with the uhci-hcd module driving a Via controller
Try using a non-UHCI controller. UHCI needs one DMA descriptor (TD) per packet, so you may be hitting a limitation there: the descriptors aren't very much smaller than those (64 byte) packets, and they're all pre-allocated.
Any limitation would show up at submit time. Either it will work or it won't work. If it fails, it's most likely a memory allocation problem.
Another way to show up at submit time would be waiting for memory to free up ... although UHCI does allocations at GFP_ATOMIC, so that particular graceful degradation doesn't exist; submit would just fail.
- Dave
------------------------------------------------------- This SF.net email is sponsored by: IBM Linux Tutorials. Become an expert in LINUX or just sharpen your skills. Sign up for IBM's Free Linux Tutorials. Learn everything from the bash shell to sys admin. Click now! http://ads.osdn.com/?ad_id=1278&alloc_id=3371&op=click _______________________________________________ [EMAIL PROTECTED] To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-devel
