Jack-Alsa performance?

[norbury brook]

Ok so I've got Manjaro working and also Yabridge and Wine.

I'm trying to set up an HP i7 laptop as a live keyboard rig.

So NO recording Just live VI playback at the lowest latency.

OK using ALSA thangs are great untill the RT cpu meter hits 80% then audio just quits..no warning of crackles or anything , just stops and I hjave to togle the audio driver to get it back...not good live.

Jack; even though this is supposed to run on top of ALSA so in theory should be inferior , has the same performance but instead of dropping the audio out it will start to crackle and distort so at least I know I'm hitting the limits and cab back off on the notes/sustain pedal.


Anyone got any suggestions as to ow to stop ASLA from stopping '80% and instead keep going like jack as its easier NOT to have to open jack first?


I'm running Pianoteq 7 and Spitfire audio cinematic pads and epic strings. The Pads is a
real CPU hog.


also any suggestions for reaper settings regarding thread priority or aggressive behaviour etc to optimise for live low latency playing...NOT recording /mixing.

M

[The Kid]

Run qjackctl, search for the sweet spot where no xrun happen, take note and apply those settings to ALSA.

[norbury brook]

Originally Posted by The Kid

Run qjackctl, search for the sweet spot where no xrun happen, take note and apply those settings to ALSA.

thanks, are you talking just buffer size though? I'm not sure what there is to alter in the ASLA settings other than this. I don't mind if things occasionally crackle I just don't wat it to shut off.


M

[The Kid]

Originally Posted by norbury brook

thanks, are you talking just buffer size though? I'm not sure what there is to alter in the ASLA settings other than this. I don't mind if things occasionally crackle I just don't wat it to shut off.


M

yeah, the minimum latency you can get away with.

[norbury brook]

Originally Posted by The Kid

yeah, the minimum latency you can get away with.

they're both about the same but jack starts to crackle when pushed ASLA stops though.. I want to use ASLA as it's simpler I just don't want it to stop, I want the crackles like Jack when it's having under runs



M

[The Kid]

ah you can change periods too. I had to use 3

[The Kid]

just make sure you run qjackctl for a long time, tweaking all the settings, until you have rock solid performance.
Maybe you'll be a little disappointed with the latency you achieve lol
I had like 10 ms, for me that's normal, I used this live for a long time, even 15 ms.
YMMV
but those settings should give you good ALSA performance and stability.
Unless something's wrong with Manjaro.
I run Mint, which is older software.

[Glennbo]

Originally Posted by The Kid

ah you can change periods too. I had to use 3

I use three periods as well, which I'm pretty sure is what the Windows version has but you can't change it there. Essentially it double buffers the output. This is how I run my 16 input UMC1820 in ALSA. 64 samples was as low as I could run it in Windows, and running it 48k @ 64 samples in REAPER is rock solid with no artifacts even when playing 24+ tracks with 100 FX including a bunch of instances of Kontakt.

[norbury brook]

Originally Posted by Glennbo

I use three periods as well, which I'm pretty sure is what the Windows version has but you can't change it there. Essentially it double buffers the output. This is how I run my 16 input UMC1820 in ALSA. 64 samples was as low as I could run it in Windows, and running it 48k @ 64 samples in REAPER is rock solid with no artifacts even when playing 24+ tracks with 100 FX including a bunch of instances of Kontakt.

@Glenn, yes I can playback large projects no problem but having 2 or 3 tracks record armed playing CPU hungry VSTi's with large polyphony is a whole different ball game however

I can feel 5ms latency when playing so want to keep it below that. Using the Pianoteq v7 I'm fine @64 samples it's the spitfire audio instruments that cause X runs at that when I use a lot of voices and RT cpu gets above 80%. I'd hoped to get nearer 90% before x runs though.

Thinking about this, is there a more efficient way of hosting VI's on linux, I'm sure I've seen a few things.

perhaps I'll have a play with sone other hosts just for fun.

with jack I can route anything anywhere so might be fun to experiment with things.

I like being able to control levels though with my Korg Nanao control which works great with Reaper/Linux..


M

[Glennbo]

Originally Posted by norbury brook

@Glenn, yes I can playback large projects no problem but having 2 or 3 tracks record armed playing CPU hungry VSTi's with large polyphony is a whole different ball game however

I can feel 5ms latency when playing so want to keep it below that. Using the Pianoteq v7 I'm fine @64 samples it's the spitfire audio instruments that cause X runs at that when I use a lot of voices and RT cpu gets above 80%. I'd hoped to get nearer 90% before x runs though.

Thinking about this, is there a more efficient way of hosting VI's on linux, I'm sure I've seen a few things.

perhaps I'll have a play with sone other hosts just for fun.

with jack I can route anything anywhere so might be fun to experiment with things.

I like being able to control levels though with my Korg Nanao control which works great with Reaper/Linux..


M

Have you set the realtime priority on the audio panel to 50, and also have you modified the file,

/etc/security/limits.conf

to give yourself unlimited memory access and realtime priority capability?

I simply added my user name to the end of the limits file with these two entries.

@glennbo - rtprio 98
@glennbo - memlock unlimited

You can verify that it worked by issuing the command,

ulimit -a

which will come back with a bunch of lines. These two in particular are the ones that will change.

max locked memory (kbytes, -l) unlimited
real-time priority (-r) 98

[Soli Deo Gloria]

Originally Posted by Glennbo

Have you set the realtime priority on the audio panel to 50

Glennbo, one question : why 50 and not 90 or any higher value?

[Glennbo]

Originally Posted by Soli Deo Gloria

Glennbo, one question : why 50 and not 90 or any higher value?

Mostly because it claims to be the "hardware default" and because I never experience any pops, clicks or droupouts with it set like that.

[Soli Deo Gloria]

Right, so, a higher value should allow a better performance if necessary; isn't it?

[norbury brook]

Originally Posted by Glennbo

Have you set the realtime priority on the audio panel to 50, and also have you modified the file,

/etc/security/limits.conf

to give yourself unlimited memory access and realtime priority capability?

I simply added my user name to the end of the limits file with these two entries.

@glennbo - rtprio 98
@glennbo - memlock unlimited

You can verify that it worked by issuing the command,

ulimit -a

which will come back with a bunch of lines. These two in particular are the ones that will change.

max locked memory (kbytes, -l) unlimited
real-time priority (-r) 98

I'm pretty sure i did as I followed the Manjiro install thread here and I remember doing things like that n the terminal


M

[Mcgiver69]

For the Manjarists out there, I think all of you will benefit by watching this video by Unfa. He is a youtuber who's been making a living as a sound designer and musician using Manjaro (previously using Debian) and Ardour. In this video he shows how he sets up Manjaro for audio production.

https://www.youtube.com/watch?v=vgrqMv3Lzfk

[s wave]

I like running a 'syslog' while using any program and 'start'boot up...' iI can just scrolls through and see xruns or problems... (like running a program from terminal - BUT keeping that terminal box open)