On Die, 2018-01-30 at 16:38 +0100, Dan Wilcox wrote:
Is it running with the *same* OS and settings?
As far as I can tell: yes. Same OS (Ubuntu 16.04), same Kernel (4.13.0- 32-lowlatency), both tuned so that "realtimeconfigquickscan" doesn't complain anymore. This includes configuring /etc/security/limits.conf, adding user to audio group, making high-precision timer /dev/hpet und realtime clock /dev/rtc readable by members of audio group, etc. I get stable performance with Ardour with the same qjackctl settings, with built-in soundcard, but also with external USB sound interface on BOTH machines.
It might be a scheduling issue with the kernel, realtime settings, crappy networking driver, etc.
I thought about that, too. But why does it affect only Pd? On the "troubled" machine - where everything else runs supersmooth - this setup suffers a couple of glitches per second (jack routing):
mpv -> Pd running [adc~]-[dac~] -> system output
The probable causes you mentioned would affect other audio softwares, too, wouldn't they?
The Pd version doesn't seem to make a difference...
Anyway, thanks for your thoughts.
Roman
On Jan 30, 2018, at 12:00 PM, pd-list-request@lists.iem.at wrote:
From: Roman Haefeli reduzent@gmail.com To: "pd-list@lists.iem.at" pd-list@lists.iem.at Subject: Re: [PD] glitches when streaming UDP Message-ID: 1517306864.2068.8.camel@gmail.com Content-Type: text/plain; charset="utf-8"
On Mon, 2018-01-29 at 10:25 +0100, Roman Haefeli wrote:
I'm working on a patch that transmits audio through UDP. The patch runs totally smooth on macOS (10.10 and 10.11) with Pd 0.48-1 and JACK as back-end. On the Linux machines I tested (all Ubuntu 16.04) with the same version of Pd I get a lot of glitches, although I'm using very similar Jack settings (128 frames/period, 3 periods).
Update: My personal, somewhat outdated laptop from 2007 has absolutely stable performance with same patch, same Pd version, same OS, same kernel. To be clear: It's only Pd that performs well on one computer and not so well on others. I get glitch-free audio with Ardour on all tested computers. So I wonder what circumstances affect specifically Pd. It's a pity the most powerful computer I have access to is in its current state not suitable for Pd projects :-(
Roman
Dan Wilcox @danomatika danomatika.com robotcowboy.com