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I am new to this world, and I want to make and record music with my new Linux installation, as I have found marvellous applications. I have seen some youtubers recomending to install the linux-lowlatency package.

Is it going to somehow delete my normal kernel? Or just add to it? Also, do I really need it? What does it do? What would I loose from my standard kernel?

Somehow I think I've heard something about the normal kernel being good enough already. Might be hallucinating.


I have followed instructions for configuring my Linux for using JACK here:

How do I configure my linux system to allow JACK to use realtime scheduling?

Is this enough? They do not talk about needing any kernel. Should I still go and install a different kernel?

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Is it going to somehow delete my normal kernel? Or just add to it?

Depends on your Distribution. From your package syntax i presume you are using some Ubuntu Derivate. They don't delete your default kernel unless you explicitly ask for it. So yes, they add a new kernel you can choose to boot from.

Also, do I really need it?

Depends on what you need and want to do

What does it do?

Ubuntu themselves explains it like this:

These are some simple guidelines provided to help you understand which kernel, and in which order, you should test to fit your use case.

  • If you do not require low latency for your system then please use the -generic kernel.
  • If you need a low latency system (e.g. for recording audio) then please use the -preempt kernel as a first choice. This reduces latency but doesn't sacrifice power saving features. It is available only for 64 bit systems (also called amd64).
  • If the -preempt kernel does not provide enough low latency for your needs (or you have an 32 bit system) then you should try the -lowlatency kernel.
  • If the -lowlatency kernel isn't enough then you should try the -rt kernel
  • If the -rt kernel isn't enough stable for you then you should try the -realtime kernel

Ubuntu makes it really easy for you to try those kernels. Just install them and experiment a little which ones fit you most.

What would I loose from my standard kernel?

Mostly Power Saving features.

Somehow I think I've heard something about the normal kernel being good enough already.

For most end user situations that's true. But if you need professional latency for let's say video editing where every single frame is essential, then you should try the other kernels.

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  • Thank you for your information! I have added a little more info to my question about some configuration I already did for real-time stuff with JACK. What do you think?
    – ivanovitx
    Mar 19, 2020 at 11:05
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https://kernel-recipes.org/en/2016/talks/understanding-a-real-time-system-more-than-just-a-kernel/

your question got me interested in reading about real-time kernel and what it actually is.

Came across the video (see link) and watch/listen at 17:30 into video he mentions JACK not needing a real-time kernel. I think this video is based on Redhat Enterprise Linux (RHEL), and I know with RHEL there is tuned power profiles which I think would be of interest to you. Look up RHEL performance tuning.

How other linux distributions deal with all this, i don't know, but would think that is a significant aspect pertaining to your question... so you would want to be specific about which linux (who's kernel) you are running... rhel, suse, ubuntu, debian, they're all different.

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  • fwiw... RHEL costs money, but CENTOS is the free version of RHEL... since you are new to this world. Anything you read regarding RHEL, applies to CENTOS. centos.org
    – ron
    Aug 19, 2020 at 18:29
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    who needs real-time operating system (not you) : youtube.com/…
    – ron
    Aug 19, 2020 at 18:52
  • ^^^ 09:10 in on video !
    – ron
    Aug 19, 2020 at 19:01

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