On Tue, 10 Nov 2015, Steinar H. Gunderson wrote: > On Mon, Nov 02, 2015 at 11:48:36AM -0500, Alan Stern wrote: > > Order 7? Maybe you're trying to put too much data into a single > > transfer and encountering problems with memory fragmentation. Try > > using more frequent, smaller transfers. > > I tried going down to 128 kB; it still happens (and if I go even further > down, I can't seem to keep up the data stream reliably, even with realtime > priority on my USB thread -- perhaps not so strange, since that's ~1000 > submits per second already). You could try getting a "zerocopy" patch to work. See this thread: http://marc.info/?l=linux-usb&m=140431709523840&w=2 Alan Stern -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
