On Thursday 17 May 2007 23:04, Alan Stern wrote: > On Thu, 17 May 2007, Laurent Pinchart wrote: > > A user of the Linux UVC driver unfortunately reported such a failure. The > > driver allocates 5 bulk URBs, and the device asked for a 2.7MB buffer. > > The system had been used for quite some time, and the user reported that > > allocating such an amount of contiguous memory made the box swap out and > > become very slow. > > Obviously the driver should be smart enough not to try and get such a > large buffer. It should allocate several smaller buffers instead.
Isn't that the job of "usb_buffer_alloc()", to allocate memory in blocks of PAGE_SIZE bytes? Is it right understood that the Linux USB stack does currently not use scatter and gathering? To me it seems like that, hence in the URB Linux only has a single DMA address value. --HPS ------------------------------------------------------------------------- This SF.net email is sponsored by DB2 Express Download DB2 Express C - the FREE version of DB2 express and take control of your XML. No limits. Just data. Click to get it now. http://sourceforge.net/powerbar/db2/ _______________________________________________ linux-usb-devel@lists.sourceforge.net To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-devel
