On Mon, Jun 10, 2013 at 5:31 PM, Oliver Neukum <oliver@xxxxxxxxxx> wrote: > On Monday 10 June 2013 17:23:46 Ming Lei wrote: >> On Mon, Jun 10, 2013 at 4:43 PM, Oliver Neukum <oliver@xxxxxxxxxx> wrote: >> > On Sunday 09 June 2013 23:18:28 Ming Lei wrote: >> >> 2), the biggest change is the situation in which usb_submit_urb() is called >> >> in complete() callback, so the introduced tasklet schedule delay might be a >> >> con, but it shouldn't be a big deal: >> >> >> >> - control/bulk asynchronous transfer isn't sensitive to schedule >> >> delay >> > >> > That is debatable.Missing a frame boundary is expensive because the increased >> > latency then translates into lower throughput. >> >> Suppose so, considered that bulk transfer will do large data block transfer, and >> the extra frame or uFrame doesn't matter over the whole transfer time. > > That is not true for all use cases. Networking looks vulnerable. > That is debatable.Missing a frame boundary is expensive because the increased > latency then translates into lower throughput. Missing uframe/frame boundary doesn't cause lower throughput since network devices use bulk transfer, which is scheduled in hw aync queue and there should always have pending transfers in the queue when submitting bulk URB to the queue. Thanks, -- Ming Lei -- 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
