Atte Andr? Jensen <atte@xxxxxxxxxxxxxx> writes: > It seems that I get quite stable performance by starting jack like > this on my P4 2.4Ghz laptop with onboard i810: > > > jackstart -R -v -d alsa -n 3 -p 256 -zt > > But what exactly does this translate to in terms of latency? Divide frame counts by (frames/second) to get seconds. Your input latency is 256/48000, 5.333 milliseconds. The output latency is three times that because of -n3, 16 msec. This is the latency due to buffering between the device and JACK. Clients may introduce additional latency depending on the processing they perform. Well-behaved clients should report this extra latency for each of their output ports. There will also be some small but unknown hardware latency due to the A/D and D/A converters. > Should I expect more? I don't know. Depends on many system-level hardware and software performance and configuration options. > I get almost the same performance under 2.4.23 with Andrew Morton's > low-latency patched and 2.6.2 with or without the mm-patch. That's probably pretty good then, though there are other things to tune besides the kernel. -- joq
