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I am using ubuntu for 4 months. I am starting to notice that, my CPU usage is becoming 100% very frequently and my system becomes unresponsive. I don't run any CPU intensive tasks, just nautilus, transmission, VLC, pidgin, firefox and chrome. I suspect, Chrome and firefox are responsible for CPU hogging. What can I do?

Ubuntu 10.10

Firefox 4.0

Google Chrome 10 Stable

PC Configuration:

Intel Core2Duo 2.53GHz


Is there any command that kills most CPU using process?

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up vote 4 down vote accepted

I have two apps that I like for checking memory usage: gnome-system-monitor and htop. Since I discovered htop, I no longer use top.

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Run top in a terminal and see what program is hogging the cpu and kill it. The most likely suspect is flash.

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Sometimes, it hogs so badly that, running a command takes time. – user Apr 20 '11 at 17:33
I second the flash suspect. I find that sometimes it gives me problems like that. Also Gnome-DO if you have it installed will sometimes freak out and use your entire CPU (which is why I use Synapse now). – zookalicious Apr 20 '11 at 18:47
Flash is notorious, especially if you use sites like Super Poke Pets which open multiple flash sessions at once. [I actually saw 80 network connections between my wife's browser and the SPP site and when she was using 1 instance of firefox on 1 SPP page with multiple habitats.] – jwernerny Apr 20 '11 at 19:53

I think that your processor has to many processes to run, especially flash and VLC, which, depending on your videos quality, may use much of your processor.

I had the same problem, and I could suggest you to run applications separately, not all at the same time, so your processor can carry fewer tasks but with better performance.

If you want to see the exactly amount of CPU each app uses, go to System->Administration->System Monitor->Processes.

Hope this is helpful.

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Indeed, when you run so many processes at once, even if alone they aren't resource intensive, they all take up resources which contributes to the 100% CPU usage. – Thomas Ward Apr 20 '11 at 17:17
I don't agree that the OP is running a lot of processes. Nautilus, Transmission, VLC, Pidgin, Firefox, and Chrome don't represent a heavy load. It is true, though, that playing videos takes a bit of CPU, especially if you're also running Compiz. The most likely suspect is some website(s) running in one of your browsers. – Scott Severance Apr 21 '11 at 5:31

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