Arch Linux

psilo357

Member

Registered: 2008-10-31

Posts: 116

Odd Problem with affinity

So, I have a quad core processor.  However, it seems it is not possible for me to use more than '25%' processor power.  When i use intensive video encoding and muxing applications like mencoder or ffmpeg, it will at times take up 25% processing power, however, during this time, i cannot do anything else with my computer, its practically in a locked down state...which is not going to work.

What is the problem here?  Why can i not get more than 25% processor utilization?  And why when I am at 25% utilization, is my whole computer locked down, not being able to do anything else?

Any ideas?  my arch install is fully updated as of yesterday.  I'm running a quad core intel processor with x86_64 archlinux install.

thanks

mikesd

Member

From: Australia

Registered: 2008-02-01

Posts: 788

Website

Re: Odd Problem with affinity

Hi,
well if an application is single threaded it will only be able to use a single core at any one time. If it pegs that core at 100% and the other three cores idle at ~0% then you could say you are using 25% of your total cpu processing power:)

Seriously though I use htop to view my cpu usage and it gives a single percentage for each core. I can peg a core and the system is still responsive. What are you using to measure performance? What are the other three cores doing when the machine is locked down? Did you use a non default kernel that may have weird SMP settings during the install?

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psilo357

Member

Registered: 2008-10-31

Posts: 116

Re: Odd Problem with affinity

I was just looking at the output from conky, it someone else conkyrc, modified just a bit so i could use it with my system...and the cpu usage only ever goes up to 25%...also, if i use kdemod's performace monitor application, i can watch the processes, and mencoder will take up 24.98%, and that when my system gets very unresponsive, i can't do anything really...

i just installed htop, and will look at it next time i'm encoding some video to see what is going on, and no, i use the default kernel...actually just updated a week or so ago when i did pacman -Syu...

peace