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WiseDraco 04-25-2013 01:54 AM

CPU consumption on idle?
 
Hello!
As i writes earlier, i get from KDE to XFCE in my celeron 900 netbook, and looking on system monitor, i see a cpu usage, even when no apps is launched, and system is in iddle state, is around 20 - 30 percent!
it was very big number, i think. i remember, many years ago Win98SE in similar states show 2 - 5 percents, and old age systems like slack 10, 11 with kde 3.5 also be under 10 - 15 percents. who eat so much cpu, when really system does nothing? and why? what is yours cpu state on idle system?

STDOUBT 04-25-2013 05:37 AM

If you're using "top" to view your CPU usage, there is something listed next to the percentage.
Run top, and read what it says next to the high percentage in the COMMAND column.
Using "top" in a terminal will give you more info than whatever GUI "system monitor" you're probably using.

WiseDraco 04-25-2013 06:01 AM

take a small investigation on that.
instrument is : asus eeepc 900 - celeron 900 mhz cpu, 1 Gb RAM, one of early SSD via IDE ( 16 Gb, really a slower than hdd, imho), slackware 14.0 32bit, installed a week ago.

using default huge kernel. initlevel on start = 4
no swap space, fs is ext4

as so: at login screen we have:

htop: 2.6 - 3.3% CPU usage, 73 Mb RAM used
top: 98.3 - 99.3% CPU idle, 409 184k memory in use

after login in KDE, idle, no open windows:
system monitor: 4.7 - 22% cpu usage,average 18-20%, 0.31 Gb RAM used
top: 88-98% cpu idle, mostly 98% idle, 899 992k used RAM
htop: 3.9 - 5.8% cpu usage, mostly 4.5%, 316 Mb mem

after shut down and login in XFCE:
system monitor: 4.5 - 22% cpu usage, avg 12 - 15%, 0.15 Gb RAM
top: 92 - 98% idle, 558 268k memory
htop: 3.2 - 7.1% cpu usage, 147 Mb RAM usage

STDOUBT 04-25-2013 06:10 AM

Run top, and read what it says next to the high percentage in the COMMAND column.

tronayne 04-25-2013 09:29 AM

If you have started KDE (even once) you have started the Evil Twins (akonadi and nepomuk); they start by default (and use a lot of resources). You can shut them off (and you probably ought to). I don't remember where they are in the KDE system menu ('cause I don't use KDE any more) but look around and shut 'em down. The blasted things will still start even if you've switched to Xfce.

This may be overkill, but you can remove the .kde directory in your home directory (that's where KDE utilities get launched) -- probably better, though, to use the KDE menu.

Something you can use to monitor things is start gkrellm -- it's a graphic "stick" that you can slide over to the edge of the screen and it shows CPU core(s), Processes, Disk I/O, network, memory and all kinds of stuff. I have set it up as a launcher in Xfce (create launcher, the command is /usr/bin/gkrellm); you can always delete the launcher when you're through with it.

On a quiescent system, your CPU(s) should be at about 0%, maybe 1% most of the time (gkrellm will show you that). There will be a lot of processes (upwards of, oh, 300 or so, but most of them are sleeping. Things do wake up and run for a while but generally, there should not be much activity displayed -- gkrellm is a nice visual indicator that will alert you to go find out what's ramping your CPU up to 50-to-100% (use top find out what it is).

Hope this helps some.


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