Levi Burton <donburton@xxxxxxxxxxxxx> writes: > I looked at jackd options, maybe someone could explain what they do for me: > > 1. -p,--period <n> frames per period (default: 1024) > 2. -n,--nperiods <n> number of periods in hardware buffer (default: 2) > 3. -H,--hwmon use hardware monitoring, if available (default: no) > 4. -s,--softmode soft-mode, no xrun handling (default: off) I'll try. Someone please correct me if I get any of this wrong. -p sets the number of frames between JACK process() calls. This must be a power of two (IIRC). -n is the number of such periods in the buffer. P*N*4 is the size of the JACK buffer in bytes. Larger buffers yield higher latency, but fewer xruns. If you need low latency, set -p and -n as low as you can without xrun problems. Reasonably well-tuned current-generation systems with a decent sound card and JACK running --realtime on a low-latency kernel can handle -p 128 -n 3 reliably. Some can do better. Tuning a system for low latency is challenging. If you don't need low latency, set -p and -n higher to insulate yourself from xruns. -H tells JACK that your sound card provides capture input monitoring. -s tells JACK's ignore xruns reported by the ALSA driver. This makes JACK less likely to disconnect ports when running without --realtime. -- Jack O'Quin Austin, Texas, USA
