On Sunday 08 October 2006 8:16 pm, Alan Stern wrote: > On Sun, 8 Oct 2006, Christopher "Monty" Montgomery wrote: > > > > I don't know what this "low-latency" thing is you're referring to. But > > > it sounds like it's trying to be _too_ low. > > > > Professional audio applications generally specify 2-5ms turnaround. > > That's from sample to playback. More than about 5ms you can't do > > digital monitor, realtime effects or a host of other useful things > > sound engineers have come to expect. > > Okay. Then there's nothing to stop you from putting 1 or 2 ms worth of > data in each URB and keeping 2 URBs in the queue at all times. Except > that you run a high risk of loss-of-sync owing to kernel latency. But > that will always be true in a low-latency application.
Right ... Monty, remember that a millisecond of IRQ latency is very possible, and is enough to cause an underrun if you don't have an urb with a millisecond's worth of data running while the system hits delays (like, another IRQ handler) before processing the previous URB. ------------------------------------------------------------------------- Take Surveys. Earn Cash. Influence the Future of IT Join SourceForge.net's Techsay panel and you'll get the chance to share your opinions on IT & business topics through brief surveys -- and earn cash http://www.techsay.com/default.php?page=join.php&p=sourceforge&CID=DEVDEV _______________________________________________ linux-usb-devel@lists.sourceforge.net To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-devel
