systemmonitor data engine: memory usage? (was: Re: System Monitor)

[Dominik Haumann]

Huhu,

On Tuesday 23 December 2008, Aaron J. Seigo wrote:
> On Tuesday 23 December 2008, Dominik Haumann wrote:
> > into my mind are System Status, System Load Watcher, System Load
> > Viewer, TimeMon, System Essentials, System Usage, ...
>
> System Load Viewer is quite straight forward and "says it all" IMHO. =)
> hope to see this in 4.3!

Agreed. I'll change this later so it's also reflected in the code.

There still seems to be a problem with regard to calculating the memory and 
cpu usage.

1. Memory
   total  = mem/physical/used + mem/physical/free
   used   = mem/physical/application
   cache  = mem/physical/cached
   buffer = mem/physical/buf
   kernel = mem/physical/used - mem/physical/application
                              - mem/physical/cached
                              - mem/physical/buf

   Showing user, cache and buffer is straightforward. In KDE3's applet we
   also had the kernel memory. This is missing and I'm calculating this
   as above. What I draw then is not anymore in the contentsRect() (see
   [1]), so probably calculation is wrong here (and the result looks a bit
   different compared to what I got in KDE3).
   Is there any documentation of what exactly those mem/physical/*
   sources describe? It's unclear.
   
2. CPU
   total  = cpu/system/
   user   = cpu/system/user
   nice   = cpu/system/nice
   kernel = cpu/system/sys
   idle   = cpu/system/idle

   Here the kernel CPU usage sometimes also seems to be less than in the
   KDE3 version. Maybe here's also going something wrong

Btw, for a screenshot of how it looks like right now, see this link:
  [1] http://imagebin.ca/view/bLt7Tfv.html
It's already in pretty good shape.

Thanks for any hints :)
Dominik