Linux: is the lowlatency kernel still necessary?

[publicradio]

I have been recording on and off, in Linux, for over a decade. I am using native Linux Reaper now, and before that LinReaper. For a long time, you had to have a lowlatency kernel to reduce buffering to anything reasonable, and before that, the realtime kernel.

I don't hear people talking about these kernels in the Reaper forums, anymore. I also noticed that when I start Cadence, it doesn't warn me anymore when I'm on the generic kernel. Does this mean the lowlatency kernel is outdated?

[GaryG]

Some distros (manjaro?) now have the low latency kernel as standard could it be you're using one of those?

I get the impression a lot of people are perfectly happy with the generic kernal nowadays but for those who want the best performance (maybe realtime guitar effects etc) then low-latency is still the way to go.

[Artie Fichelle]

I am using the Liquroix kernel, that is said to be one of the best low latency kernels. Easy to install for example check linuxcapable.com

[glokraw]

Hi, and happy weekend! I remember reading about various timing improvements being included in kernels used as defaults, so I expect various improvements occur throughout the year. I have an old i7 3.4gigahurts quadcore, 8 thread cpu with 8 gig of ram, and for years have been happy with the RT kernels in Puppy linux and AVLinux, the one most often used now is

6.0.0-9.1-liquorix-amd64 #1 ZEN SMP PREEMPT_DYNAMIC liquorix 6.0-5~mx21+1 (2022-11-18) x86_64 GNU/Linux (say that 5 times real fast )

I'm happy with the results, and will look for a used but better computer after the taxes get paid and some roof repairs get manhandled
Cheers

[FranklyFlawless]

Does this mean the lowlatency kernel is outdated?

I cannot answer for Cadence, but I have never needed any low-latency kernel, including Liqourix, as necessary for my music production work.

[pljones]

I wouldn't expect latency on any platform to be an issue with "in the box" production work. It's generally where you're doing real time processing (i.e. Audio or MIDI input through to Audio or MIDI output -- generally audio taking up more CPU cycles, of course) and expecting a minimal time delay (i.e. latency).

[audiojunkie]

I have been recording on and off, in Linux, for over a decade. I am using native Linux Reaper now, and before that LinReaper. For a long time, you had to have a lowlatency kernel to reduce buffering to anything reasonable, and before that, the realtime kernel.

I don't hear people talking about these kernels in the Reaper forums, anymore. I also noticed that when I start Cadence, it doesn't warn me anymore when I'm on the generic kernel. Does this mean the lowlatency kernel is outdated?

The main thing to be aware of, is that there has been on-going work to mainline the real time patches into the generic kernel. While the work is not yet complete, most of the patches are now there, and with the right configuration settings, the generic kernel does nearly as well as a custom compiled low-latency kernel. This is a big deal, and more and more people are finding that they don't necessarily need a low-latency kernel anymore.

The main linux kernel boot parameters you need to be aware of are /preempt=full and /threadirqs

By putting these parameters into your GRUB, you are effecting switching your generic kernel to run like a low latency kernel. There have been recent developments and additional kernel parameters that have been found useful as well. So much so, in fact, that Ubuntu is planning on slowly moving away from using a custom compiled low latency kernel, and plan on using a generic kernel with these parameters. So, to answer your question, low latency is still needed, but a custom compiled kernel is not necessarily needed for most users.

To see more information on the additional kernel boot parameters that help a generic kernel run like a low-latency kernel, read the following post:

https://linuxmusicians.com/viewtopic.php?t=27089

Personally, I think this is great news!!

[uOpt]

It is hard to imagine that this still matters for audio. But only testing will tell and I don't think anybody has done so lately.

So you tell us on Monday

[glokraw]

It's also important to know what software you need that will dominate your cpu, and learn to deal with it. Some famous software still works best in single-core mode, with preferences panels to select that. Some daws and plugins are better at multi-core xyz than others. Some samplers have good disk streaming, some might not. Kernels provide a workspace, but it's on the users to fill the space wisely, and know how things work and interract.
Know what products to avoid, and which ones you can rely on. Kernels won't stop a trainwreck. But having one stable system you don't mess around with, and a second one for experiments, will save a lot of problems from getting off the ground.
Cheers