Cadence and KDE activities

Unofficial support for the KXStudio Linux distribution and applications.
More info at http://kxstudio.linuxaudio.org/

Moderators: MattKingUSA, khz

Post Reply
paul
Established Member
Posts: 226
Joined: Wed May 07, 2014 9:50 pm
Location: UK
Has thanked: 1 time
Been thanked: 1 time

Cadence and KDE activities

Post by paul »

One of the KDE tools that I use most is "activities".
I have for example an activity "Desktop", to use my laptop normally (checking email, etc) with power saving settings.
The activity "Audio" has instead maximum CPU performance and related settings.

It would be very nice to have the following thing: whenever I switch to "Audio", Cadence selects my external (USB) interface instead of the default sound card (iff it is plugged in), and loads a pre-built patchbay.

The KDE activity manager allows to run a script whenever you load an activity. This is probably the only way to link Cadence and activities without hacking KDE itself. But...is there a way to send instructions to Cadence via a script? Does it take command line input? In particular, I would like to send the instruction in italic above.

Any suggestions?
Keep on rocking in the free world!
paul
Established Member
Posts: 226
Joined: Wed May 07, 2014 9:50 pm
Location: UK
Has thanked: 1 time
Been thanked: 1 time

Re: Cadence and KDE activities

Post by paul »

Ok, thank you.
I'll post the final script as soon as I get something useful and working!
Keep on rocking in the free world!
Snap
Established Member
Posts: 159
Joined: Mon Jan 07, 2013 7:27 am

Re: Cadence and KDE activities

Post by Snap »

I have for example an activity "Desktop", to use my laptop normally (checking email, etc) with power saving settings.
The activity "Audio" has instead maximum CPU performance and related settings.
How you do that? I've been experimenting with activities and indicator-cpufreq settings and cannot make it work that way. If set ondemand, for example, it remains on demand for all the activities when switching between them. Switching to Audio activity doesn't push it back to Perfromance if it was changed in other activity before. It would be just perfect if different CPU states would be associated to different activities.
paul
Established Member
Posts: 226
Joined: Wed May 07, 2014 9:50 pm
Location: UK
Has thanked: 1 time
Been thanked: 1 time

Re: Cadence and KDE activities

Post by paul »

Snap wrote:How you do that?
With a script, as explained here: http://blog.tube42.se/?p=1225.
Snap wrote:If set ondemand, for example, it remains on demand for all the activities when switching between them. Switching to Audio activity doesn't push it back to Perfromance if it was changed in other activity before. It would be just perfect if different CPU states would be associated to different activities.
Oh that, I can't. I wish too! Unfortunately there is no option to run a script every time you switch to a different activity, only every time you load that activity. What I do is closing activity "Desktop" when I start using "Audio", and viceversa. This way, when I switch back to "Desktop", I load it, and the script sets the CPU to ondemand. Also, this way, while on "Audio" I'm not running the "Desktop" widgets (and I use all the power for DSP).
If you switch often between different activities, this is of course not the best option, but I can't see any other solution. (Mostly, since not too many people use activities, I doubt there will be additional features in the next releases.)

If anyone has a workaround on this, it would be welcome!
Keep on rocking in the free world!
Snap
Established Member
Posts: 159
Joined: Mon Jan 07, 2013 7:27 am

Re: Cadence and KDE activities

Post by Snap »

It should be possible to make a script switching the CPU state, then killing the indicator-cpufreq process and a few more not needed processes, and finally switching the activity itself. But my bash scripting skills are very limited. I'm only able to make very very simple scripts. :cry:

Anyway, I use a specific user for audio and a different one for the rest. But it would be nice having the chance to simply switch activities. Activities is the most underrated and less understood feature in KDE, while IMHO, it's one of the most powerful reasons to use KDE. For me it's Kwin, Activities, Dolphin and Krunner what makes the difference and what fully justifies choosing to use a very heavy DE instead of a much lighter window manger way easier on resources. The only actually annoying thing I find in activities is not having independent panels per activity forcing users to be tied to the damned inconvinient plasmoids on the desktop. I hope it gets implemented in KF5. Aside of that, It's just a killer tool.
Post Reply