July 2018 - Arch-proaudio - lists.archlinux.org

[arch-proaudio] 'proaudio-settings' package
by bill-auger 01 Aug '18

01 Aug '18

aside from the new 'realtime' package, i would like to propose an audio-specific optimizations package of the sort that other av-centric distros commonly have - a package that contains goodies such as the 'realTimeConfigQuickScan' and 'rtirq' scripts that will inform the user how best to optimize their hardware IRQ and PCI latency and such; and other suggestions from the linuxaudio wiki[1] that can be automated, such as selectively disabling and re-enabling unnecessary services (screensaver, printing, *ehem* pulse), a .jackdrc with smaller buffers than the default config, etc i did a side-by-side comparison with the analogous proaudio-settings optimization packages from each of parabola, kxstudio, and ubuntustudio - they are all nearly identical in what they accomplish; but AFAIK currently arch does not have an analogous package - here are some examples of what they do: -------- using 'parabola-proaudio-settings'[2] as a reference: # custom kernel parameters to sysctl.d folder /etc/sysctl.d/99-sysctl.conf # By default, swap frequency defined by "swappiness" is set to 60. By reducing this number to 10, the system will wait much longer before trying to write to disk vm.swappiness = 10 # inotify watches for changes to files and reports them to applications requesting this information. When working with lots of audio data, a lot of watches will need to be kept track of, so they will need to be increased. fs.inotify.max_user_watches = 524288 -------- # ensure the ALSA MIDI driver is loaded /etc/modules-load.d//alsamidi.conf # If you want to use any MIDI hardware you need to ensure the ALSA MIDI driver is loaded snd_seq_midi -------- # recommended initial settings for jack /etc/jackdrc /usr/bin/jackd -P89 -t2000 -dalsa -dhw:0 -r44100 -p256 -n2 -Xseq -------- # systemd service # increase the highest requested RTC interrupt frequency (default is 64 Hz) /etc/systemd/system/parabola-proaudio-settings.service /etc/parabola-proaudio-settings.sh #!/bin/sh echo 2048 > /sys/class/rtc/rtc0/max_user_freq echo 2048 > /proc/sys/dev/hpet/max-user-freq cpupower frequency-set -g performance echo noop > /sys/block/sda/queue/scheduler -------- # extra virtual midi ports /etc/modprobe.d/snd-seq-dummy_16.conf #Creates extra virtual midi ports options snd-seq-dummy ports=8 -------- kxstudio 'kxstudio-default-settings'[3] has the following also: /etc/sysctl.d/10-kxstudio-sysctl-rules.conf dev.hpet.max-user-freq = 2048 -------- ubuntustudio 'ubuntustudio-default-settings'[4] suggests that 3072 is a better value for dev.hpet.max-user-freq (although they have it commented out) #dev.hpet.max-user-freq=3072 -------- both kxstudio and ubuntustudio have the following also (this is the only concern that is specified in the new 'realtime' package): /lib/udev/rules.d/99-kxstudio-udev.rules /lib/udev/rules.d/40-timer-permissions.rules KERNEL=="rtc0", GROUP="audio" KERNEL=="hpet", GROUP="audio" -------- [1]: https://wiki.linuxaudio.org/wiki/system_configuration [2]: https://git.parabola.nu/abslibre.git/tree/pcr/parabola-proaudio-settings?id… [3]: https://github.com/KXStudio/KXStudio/tree/master/default-settings [4]: https://git.launchpad.net/ubuntustudio-default-settings/tree/

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[arch-proaudio] Introducing: dedicated realtime group (not only for jack/jack2)
by David Runge 30 Jul '18

30 Jul '18

Hi all, I've created the package realtime-privileges [1], that is now an optional dependency to jack2 [2]. I have removed the realtime privileges bound to the audio group (that are redundantly packaged in jack and jack2). For now this is going to be in [community-testing], until a developer rebuilds jack [3], which will also make it depend optionally on the realtime-privilege package. Afterwards these changes will be rolled out to [community] and [extra]. To sum up, the following will change afterwards: Instead of using the audio group to acquire realtime privileges, you will have to use the dedicated group 'realtime' to which you can add your user. Being part of the audio group is only required to access certain audio hardware from then on! Thanks to Joakim Hernberg (who maintains linux-rt [4] in the AUR), I've now also added access to /dev/cpu_dma_latency, which grants applications the possibility to prevent CPU idle states on demand. If you spot anything that should be changed, let me know! Best, David [1] https://www.archlinux.org/packages/community-testing/any/realtime-privilege… [2] https://www.archlinux.org/packages/community-testing/x86_64/jack2/ [3] https://pkgbuild.com/~dvzrv/extra/jack/PKGBUILD [4] https://aur.archlinux.org/packages/linux-rt/ -- https://sleepmap.de

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[arch-proaudio] Audio packages moved from AUR to community
by SpotlightKid 28 Jul '18

28 Jul '18

Hi Dave, when you move packages from AUR to community and use my PKGBUILD files as a basis, I would appreciate it, if you acknowledged my work by putting an appropriate "Maintainer:" line in the PKGBUILD. Also, why did you drop the python2 variant from python-jack-client? Chris

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