The CPU (Central Processing Unit), is the chip in the computer that actually performs the operations and calculations that are done as a program runs. It is essentially what executes a program.

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How to find which Process is causing High CPU usage

Is there any way to find out from terminal which process is causing high CPU Usage ? It would also be useful to order processes in descending order of cpu Usage
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6answers
1k views

Is there a way to limit overall CPU consumption?

My laptop (an HP with an i3 chip) overheats like crazy every time I run a resource heavy process (like a large compilation, extracting large tarballs or ... playing Flash). I am currently looking ...
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1answer
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In Linux “top” command what are us, sy, ni, id, wa, hi, si and st (for CPU usage)?

When I issue $ top in linux, I get a result similar to this (see here). One of the lines has CPU usage information represented like this: Cpu(s): 87.3%us, 1.2%sy, 0.0%ni, 27.6%id, 0.0%wa, ...
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2answers
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How to get information about word, address size, address bus size, data bus size and instruction bus size?

I was wondering how to get information about the following things from the command line in Linux: word (i.e. the size that the CPU can process at one time, which may not be the OS bit-depth), ...
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1answer
6k views

What are software and hardware interrupts, and how are they processed?

I am not sure if I understand the concept of hardware and software interrupts. If I understand correctly, the purpose of a hardware interrupt is to get some attention of the CPU, part of implementing ...
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688 views

Xorg increases cpu usage over time

I've had quite a strange phenomenon with Xorg for some time now: After logging in to my laptop (specifics below) the cpu consumption of Xorg increases monotonically, even if the computer is idle and ...
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2answers
1k views

Program to test CPU load and process priority

I am running some test on Amazon EC2 instances and we want to make the CPU always busy at above 80%. What I have is a program main that needs to run in high priority and I want to launch another ...
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2answers
542 views

Finding MFLOPS using Linux

How can I find out the Mflops on my linux computer? I can see the bogomips on my /proc/cpuinfo but I don't see any Mflops on that file: $ cat /proc/cpuinfo | grep -ie mips -ie flops bogomips : ...
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2answers
985 views

How to find if hyperthreading is enabled on FreeBSD

Is it possible to find out if hyperthreading is enabled within the BSD kernel of a given machine without watching the boot up sequence?
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1answer
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Why Process CPU % Usage larger than Total CPU Time

When I run the TOP command, a process shows 1208% cpu usage and the total CPU usr time is 81.7% with IRIX mode on. When I change to IRIX mode off, the process shows 99% cpu usage and the total user ...
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454 views

Overheating results in system shutdown

I have been having an overheating issue which makes my laptop shutdown immediately. Is there anyway to monitor the temperature from the sensor and scale down the CPU frequency to avoid that problem? ...
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4answers
2k views

How to limit resource usage to save CPU+RAM for a certain process?

I have a dev server on which sshd sometimes stops working because the machine runs out of RAM. Yes we are running low on memory and upgrading is not a feasible choice right now. What I want to do is ...
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How to check that AES-NI is supported by my CPU?

Howcan I check if my CPU supports the AES-NI instruction set under Linux/UNIX.
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1answer
765 views

Overclocking software for Linux?

Is most overclocking done strictly at the BIOS level, or is there a way to do it from a running operating system? And if so, is there a way to do it from Linux? I'm running Ubuntu presently and am ...
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2answers
2k views

Slow down the CPU

I tried to slow down my CPU with powernowd and cpufreq-selector. I hoped that with lower frequency it will be less hot and I won't hear my fan every time I will run internet radio. I used the ...
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1answer
366 views

Queries about top command

top command shows the process cpu utilization, and it when we sum the cpu utilization of all the processes then it goes greater than 100%. And how can it shows the cpu utilization of each process( ...
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5answers
404 views

performance monitoring

Is there some performace monitoring tool which would run in background gathering info about all system activity? Somethimes my system (Arch linux, 32 bit) slows down terribly and the top utility ...
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3answers
3k views

Understanding top and load average

I'm observing a high load average on a certain machine (about 9) in all three load fields. I understand load as the number of processes in state "run" / currently desiring CPU time. Am I correct at ...
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2answers
7k views

Run process with higher priority

I want to run mplayer with higher priority than any other processes, including the IO-processes. How can I do that?
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1answer
409 views

xorg performance in openoffice

I've just been monitoring my cpu usage in openoffice calc when cells have been copied vs when they haven't and seen a dramatic increase in cpu usage for the Xorg process. The additional rendering ...
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How can I have 400% CPU occupied on 2 cores

I understand that Σ(%CPU) ≤ logicalcores*(1+ε) (where ε is measure and rounding error). But, how can I have on a 2 core system 2 different processes, each taking 200% of CPU (as measured by htop)? ...
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2answers
194 views

How can I chase a program who is rising up my laptop's temperature?

After 40 days of non-upgrading I came back from a trip and I decided to dist-upgrade my Debian Sid box. Everything went fine but after rebooting I noticed that the temperature was 15°C over its ...
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3answers
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How come I installed Ubuntu 64 bit on a Pentium 4 machine?

I have just tried booting the Ubuntu 10.10 64 bit live USB on this machine and to my amazement everything works fine. I even installed the system, after which I checked with uname -a and the result is ...
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3answers
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Video player that uses multiple CPU/GPU cores in Linux?

I've got a relative with a four-cour AMD Phenom II 3.0 gHz CPU (can't remember exact specs) and ATI 5750 1GB graphics card, running Ubuntu 10.04. Right now I am aware of VLC and Mplayer for playing ...
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2answers
418 views

Will enabling Hyper-Threading create two virtual half-speed processors?

If I enable Hyper-Threading for my netbook which has an Intel Atom (1.6 GHz) will the kernel see two virtual 800 MHz processors?
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How can I set the processor affinity of a process on Linux?

The question is all in the title: How can I set the processor affinity of a process on Linux?