Installing a Realtime Kernel
- Inicie sesión ou rexístrese para enviar comentarios
Hello, I am interested in install a real-time kernel in Trisquel. I have been using audio engineering software and have been experiencing audio-dropouts and latency issues and I heard the real-time kernel helps with this. Would anyone out there know how I can approach installing this in a painless way? I also wonder if this real-time kernel is Libre. Any help with this is very appreciated.
David
There was one GNU-compatible real-time kernel released under the GPLv2-
RTLinux. However, the website's been down for some time now. I think the
project's been abandoned. There is an FTP repository from which you can
download the source for RTLinux (here: ftp://ftp.rtlinux-gpl.org/pub/rtlinux),
but it requires a username and password. And I have no idea how to go about
getting one. The repository hasn't even been updated since 2001, so I wouldn't
recommend even trying this with a modern system. The world of GNU/Linux has
changed a lot since 1998 (when RTLinux was written). The mailing list archives
no longer exist, as do the people who once hosted the list, who have been taken
over by spammers.
Basically, the project is dead. If you want a newer version of Linux-libre,
then you can use jxself's repository. There are instructions on how to do this
here: https://trisquel.info/en/wiki/update-linux-libre-kernel under 'Using
jxself's repository'.
Kia ora David
I'm also interested in getting better performance out of GNU/Linux for audio/video editing purposes. My technical experience here is limited but here are some things worth considering:
* firstly, is software really the bottleneck? Is your hardware really up to the task? Do you have enough processor power, RAM etc?
* is your hardware well supported by libre firmware/ drivers? Annoyingly this is not an either/or (ie it works or it doesn't). Fully libre GNU/Linux often supports some of the functions of your hardware and not others. The secrecy of hardware vendors is at fault here, not GNU/Linux developers, but for now its something we have to be aware of.
* is your machine sufficiently cooled? Because I use laptops, and repurpose older PCs, I have seen what a difference it makes when a PC has sufficient fans, heatsinks, ventilation etc to keep it cool when it's working hard.
* is your OS as minimal as possible while still allowing you to do your work? Some graphical applications on GNU/Linux including desktop managers like GNOME have become as bloated and resource hungry as Windows. Have you tried using Trisquel Mini, or another more lightweight desktop like XFCE or LXDE? Have you tried Musix?
http://distrowatch.com/table.php?distribution=musix
* Do you have a decent graphics card? I've heard there are ways to use the graphics card to do some of the heavy-lifting in audio processing too (no idea how though).
* do you have a second computer that you could run as a headless system (no graphical desktop) for your audio processing, while operating it remotely from your main computer?
Again, these are all just things to think about. Sorry I can't give any specific advice for successful experience, but from everything I've read, doing audio/video work on GNU/Linux is a pretty bleeding edge area all round.
Thank you kindly for the trouble shooting ideas. My laptop is very new and in good condition, sufficiently cooled, etc. I haven't tried Musix yet and am curious about trying Ubuntu Studio, but I think I want to stick it out as much as I can with the Libre philosophy. I was poking around and it seems that rcconf may have helped me:
http://www.webupd8.org/2009/10/how-to-disable-disable-cpu-frequency.html
I guess you could patch Linux-libre with this
https://rt.wiki.kernel.org/index.php/CONFIG_PREEMPT_RT_Patch
Here's how to compile it then
https://trisquel.info/en/wiki/compiling-gnu-linux-libre-kernel
This just may be what I need. Hrm. Intimidating. I'll look into this some more. Thanks!
Using a Trisquel's low latency kernel doesn't help?
How do I know if I am usign a low latency kernel? By the way your icon makes me think of the logo for that password manager software, Dashlane. Kind of an amusing coincidence:
As far as I understand (and as vita_cell wrote), computer-assisted music requires low latency. Trisquel has such kernels in its repository. In fact a low latency 3.13 kernel even become the default with Trisquel 7. There is a good chance you are using it if you installed Trisquel 7 from scratch (not sure about the update from Trisquel 6).
The following command (to be executed in a terminal) will tell you what version of the kernel you are currently using:
$ uname -r
If that version does not end with "-lowlatency", then install a low latency kernel from the package manager (e.g., using the "Synaptic package manager" in the "System settings"). The package is named "linux-image-lowlatency" for the default 3.13 version. But more recent versions are available as well. For instance, choosing the package named "linux-image-lowlatency-lts-utopic", you would install a 3.16 version.
Thanks! I'm using: 3.13.0-66-lowlatency
I guess the issues I had, were something else.
So, I'm not sure if this did the trick but for now I just used "rrconf" to disable cpu frequency scaling:
http://www.webupd8.org/2009/10/how-to-disable-disable-cpu-frequency.html
Seems to work. I haven't noticed any issues.
- Inicie sesión ou rexístrese para enviar comentarios