Hello,

What happens when an Activity is stopped? I continue to see App utilizing memory in system monitor. The concerned app usually don't register a high CPU usage so I can't tell if it is actually running?

Will I lose all windows and any unsaved work If I restart my system?

Thanks.

Depends on the application - the applications can listen to activity changes and act accordingly.
Please don't misconnect "process" and "window" - they have no connection at all. Just that a window is on a particular activity does not mean the process would somehow be (that would be a model for the client to implement internally)

Afaik nobody does really know what activities are supposed to be. Afa the WM is concerned, they're just a NETWM incompliant system of virtual desktops.

If you restart the system, applications can intercept that and require you to save data. if they don't, their data changes are lost. Up to the application as well.

PS: you want to "kill -STOP $PID" a process to make it stop using the CPU, this has no impact on memory (the kernel will do about the right thing for you when you run out of physical memory and provide a swap device)

PPS: be WARNED that stopped processes still receive input events (mouse clicks, keyboard etc.) and will process them as soon as you send "kill -CONT" them!

luebking wrote:Depends on the application - the applications can listen to activity changes and act accordingly.
Please don't misconnect "process" and "window" - they have no connection at all. Just that a window is on a particular activity does not mean the process would somehow be (that would be a model for the client to implement internally)

Afaik nobody does really know what activities are supposed to be. Afa the WM is concerned, they're just a NETWM incompliant system of virtual desktops.

If you restart the system, applications can intercept that and require you to save data. if they don't, their data changes are lost. Up to the application as well.

PS: you want to "kill -STOP $PID" a process to make it stop using the CPU, this has no impact on memory (the kernel will do about the right thing for you when you run out of physical memory and provide a swap device)

PPS: be WARNED that stopped processes still receive input events (mouse clicks, keyboard etc.) and will process them as soon as you send "kill -CONT" them!

In a nutshell, stopping an Activity seems to simply have made it inaccessible through general means like Meta+Tab to shuffle through them.

If stopping an Activity doesn't do anything to the app then stopping them don't make any sense unless I am not going to use them for a long time but then why would you create and setup activities for task that you aren't going to do often and need a separate clean environment to do.

Stop sounds like it freezes that Activity and frees the resources which it obviously doesn't do. As a matter of fact I am afraid I might lose work if I leave too many tabs open in Chrome or Firefox in one Activity and try to open numerous other ones in another Activity.

I wish we had dynamic workspaces like GNOME guys that gets created and destroyed without manual user intervention. Virtual Desktops and Activities have are almost same features.

This is a misconception:
I do not know what activities are or are supposed to be, but they are NOT a substitute to virtual desktops.
KWin handles activities, but that's pretty much random (in fact, there's or used to be a compile time option to deactivate activity support)

Afair a kwin script for dynamic virtual desktops is flying around somewhere, but I could not find it at hand.
However, this is not an option for general behavior, because shuffling around windows from one desktop to another because an inferior desktop got (temporarily) empty can suck mighty - you start to play hide and seek with your windows.

Magic freeing of resources is obviously not possible. The data *has* to go somewhere - or is lost.
=> Add a swap partition or file for the kernel to stuff data on demand. It's "smart enough™" to swap out the data that are "currently not in use™"

Here as well, stopping an activity *cannot* mean to simply stop/swap out all processes that may or may have not windows on that activity.
One would require a way to really attach a process to an activity (*implying* its windows) - but that would require to define what activities are meant to be (ie. subsessions, but the reply was "no" on this - I never got a positive answer, though. And I don't use activities, because they're nothing and thus not good for anything by definition. Sorry, but period)

Thank. I understand your sentiments. There is simply no documentation available for Activities unless one is willing to dig in the code.