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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Top “id” is using 50-99% of CPU

My i386 Lubuntu install is running with a constantly 100% CPU. Using top I have diagnosed "%id" as using up a lot of CPU, usually between about 50% and 99%. Why is this happening, and how can I stop ...
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25 views

Is there a brief way to view the top resource usage(CPU, memory or even bandwidth) of a program after its running?

I know I can use top to view the overall real-time CPU & Memory usage, and nload for overall real-time bandwidth usage. But I wish to view the maximum(or average) CPU, Memory, & bandwidth ...
2
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1answer
1k views

/proc/cpuinfo showing zero cpu clock speed

I saw an interesting issue where the cpuinfo file from /proc filesystem shows the cpu clock speed as zero. It is a physical host with no virtualization. Can someone explain to me some probable reasons ...
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3answers
54 views

Store CPU utilization into CSV file

OS: Debian 8 x64 I'd like to log every 5 seconds the CPU percentage into a CSV file in the format below: YYYY-MM-DD HH:MM:SS,CPU% I'm not familiar with how to use the top program to calculate the ...
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1answer
14 views

Kernel panic – not syncing: Fatal machine check on current CPU

In the latest few weeks, my machine rebooted a few times with this kernel panic error. It's a fedora 21, Linux 4 machine on an AMD E-350 APU. I didn't observe any pattern. When I reboot, the BIOS ...
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3answers
303 views

Externaly limiting number of CPU cores used

I need to externally limit a process/session to a certain number of cores. Are there any other possibilities than CPU affinity (I don't like the need to specify the actual cores) and cgroups (hard to ...
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0answers
28 views

Kernel - Measuring the rate of timer interrupts

I am working on optimizing kernels of my boxes for telephony, which involves (among other things) adjusting the HZ rate and the preemption model. Initially the kernel was compiled with the default ...
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3answers
8k views

Bash script that automatically kills processes when CPU/memory usage gets too high

I have created a script that kills processes if CPU and/or memory usage hits 80%. It creates a list of killed processes when this happens. What can I do to improve it? while [ 1 ]; do echo echo ...
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1answer
65 views

cpulimit on a bash script which runs other commands

I have a bash script which runs other cpu-intensive commands . When I apply cpulimit on the bash script, the output of top shows processes for the commands inside the script still run without ...
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1answer
23 views

Use NVIDIA graphic card as regular resource

I don't use my graphic card anymore, but it is still laying there, idle. Is there a way I can turn it back on and use it just a regular, additional CPU/RAM for my laptop?
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how practical the number of cores in Android

I've often wondered how practical the cores usage in Android smartphone. I'm asking here because Android is based on Linux. I'm looking from technical perspective. The articles that I've read so far ...
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1answer
1k views

Intel Turbo Boost apparently activated for no reason?

The other day, I reinstalled my operating system (Crunchbang, fork of Debian). For some reason my fan has been running at full speed (and blowing colder-than-room-temperature air) even though I'm ...
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1answer
51 views

Linux cgroups: limit CPU usage in absolute values which do not depend on CPU speed

I have a server with a 2.4GHz processor. And there are several cgroups, each one allowed to use 25% of CPU. That's equal to 600MHz. Then I replace the CPU with a faster one, let's say 3.0GHz. If I ...
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0answers
36 views

Change system properties(name) under linux

Sorry for the title if is not clear. What I wondering can I change somehow under linux( ubuntu / redhat ) the name of processor like in windows by registry edition? What I mean is currently when I ...
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0answers
268 views

What's limiting my CPU usage in forked processes?

I am running some long-running programs (for scientific purposes) on a multi-core Linux box. The processes are controlled by a small daemon which restarts the next job when one finishes (I run 3-6 at ...
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1answer
808 views

Linux Mint CPU cores balancing and high temprature

I'm using Linux Mint. My laptop has a Corei5 CPU. When I check the system monitor, it shows that the CPU 1 usage is between 90 to 100% and CPU 2,3,4 are less than 5%. why it doesn't balance processes ...
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2answers
5k views

Get CPU utilization stats from C program

I want to read the CPU utilization stats from a C program, I am interested in the percentage of use of CPU, steal time etc. These stats are shown in the 3rd row from the top command. I tried to parse ...
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2answers
705 views

Why I can not use all the 100% potential of CPU?

I am using my computer clusters to run a MD C program but I can not use full potential of those clusters. But the this node have 16 CPUs and I also only give 15 jobs for those CPUs. But I can not ...
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2answers
82 views

Difference between two linux machines

I have two machines and I am trying to see which one is more powerful machines. I can check memory and cpu but not sure how to understand other things from lscpu: Here is machineA "lscpu" result: ...
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1answer
11 views

Relation between Interface Speed and Processing times

i have a question regarding processing time delays, i want to know is there a relation between the rate of data packets received and their processing time at the receiving host or is the processing ...
2
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1answer
31 views

Set CPU affinity for the specific program?

How can I set CPU affinity for the specific program (say gzip) to always run on specific core or cores (core 1, for example)? I read about taskset, but can it be used before program is actually used ...
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4answers
45k views

What do the flags in /proc/cpuinfo mean?

How can I tell whether my processor has a particular feature? (64-bit instruction set, hardware-assisted virtualization, cryptographic accelerators, etc.) I know that the file /proc/cpuinfo contains ...
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1answer
32 views

Threads vs interrupts

What does it mean when threads are time-sliced? Does that mean they work as interrupts, don't exit while routine is not finished? Or it executes one instruction from one thread then one instruction ...
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3answers
129 views

How to know number of cores of a system in Linux?

I wanted to find out how many cores my system has. So I searched the same question in google. i got some command like: $ lscpu command. When i tried this command, it gave me the following result: In ...
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2answers
3k views

Why does top report the incorrect CPU usage?

I have a machine with Intel(R) Xeon(R) CPU E5520 visible as 16 logical cores (8 with HT). If I run something to eat CPU time (single threaded) top correctly reports 100% CPU usage for the process but ...
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/proc filesystem - getting useful information

I'm trying to understand the values in /proc/PID/status. I want to calculate cpu% & mem% used by PID, similar to top bash command. For Memory percentage usage I can do the following (correct me ...
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2answers
56 views

Is there a good resource monitoring tool in linux?

I've been looking for a good resource monitor in linux for a couple of hours and all I have found is conky. Specifically I've been looking for something to monitor my core clock speeds. I've found ...
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0answers
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cpu temperature is higher than usual after installing xubuntu

I have installed Xubuntu 14.04 on Asus S550CB but the system becomes warmer than usual. So I tried to configure lm-sensors and saw cpu temperature is about 50 degrees. I guessed that some drivers are ...
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1answer
43 views

Resource (CPU time and memory) limitation and termination of a process upon violation in Linux

The problem: Given a process, limit the resources it and its child-processes can use. I.e. set CPU time and virtual memory quotas. When the process group exceeds one of the limits, terminate it, ...
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1answer
33 views

Monitor Cpu & Ram Uasge Via Web

Sorry about that newbie question. But does anyone know how to make or where to find a script that will monitor CPU and ram usage, so i will be able to use it at my admin panel on web? I'm running a ...
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0answers
32 views

Get AMD 8320 CPU temp?

I'm looking to get the CPU temperature of my AMD FX-8320 chip. I have lm-sensors installed and I've run sensors-detect saying yes to all of the prompts. I also have the kmod system service running and ...
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4answers
13k views

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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4answers
3k views

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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7answers
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Getting cpu usage same every time.

When I execute following command to get cpu usage , I get nice + user cpu usage. top -b -n1 | grep "Cpu(s)" | awk '{print $2 + $4}' Output: 14.5 Here I am getting problem is that the output ...
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2answers
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Why is the range of load average not 0-1+ for all cpu's together?

I know that load average is 0-1(or 0-1024) per cpu. E.g a busy quad-core can have a load average of 4.0 or higher. (e.g if there are many tasks). I understand it can be huge like 100+ etc. I also ...
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5answers
2k views

How to find which machines are idle on a cluster of many nodes

I run measurements on a cluster consisting of 32 nodes/machines. I do not require all nodes, only 4, for example. The problem is most of the time, the nodes are busy with other people running their ...
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0answers
112 views

Why is 'steal' time gradually increasing?

I'm tracking CPU usage on a VM on a lightly-loaded host. Everything appears to be functioning normally on all the VMs, but collectd is reporting a gradually increasing 'steal' time: The actual ...
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3answers
169 views

Linux & Linux-Software: Advantages of a multi core processor [closed]

I plan to get a new notebook and try to find out if a quad-core processor gives me any advantages over a regular dual-core machine. I use common Linux Distributions (Ubuntu, Arch etc.) and mostly ...
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1answer
41 views

Show CPU core usage for parent process and its child processes

Is it possible to display CPU core usage just for a single process and its child processes on Linux?
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2answers
59 views

Telling Linux kernel *not* to use certain CPUs

I'm trying to run some benchmarks on a multicore machine and I'd like to tell the Linux kernel to simply avoid certain cores unless explicitly told to use them. The idea is that I could set aside a ...
1
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1answer
94 views

How to ensure ssh via cgroups on centos?

When some cpu-intensive processes are running on the server, chances are that we could not log in to this machine with error 'operation timeout' via ssh command. According to this post answered by ...
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0answers
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CPU Scheduling incredibly slow with large difference between total execution time and actual CPU time - Ubuntu Full-Disk Encryption enabled

Admittedly, I am running on a build that is no younger than five years old at this point and the system is not going to be incredibly fast. However, at the same time, the run-times I am observing are ...
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2answers
72 views

How to determine the maximum number to pass to make -j option?

I want to compile as fast as possible. Go figure. And would like to automate the choice of the number following the -j option. How can I programmatically choose that value, e.g. in a shell script? ...
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42 views

High %sy cpu usage , server is very slow

On one of the server we are noticing high %sy usage due to which server is very slow. Below is strace count for syscall. What will be the reason for high %sy usage. % time seconds usecs/call ...
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1answer
48 views

CPU Utilization & Memory Utilization script

I want to show CPU & Memory utilization. Like I use command of mpstat and get an output: 01:04:19 PM CPU %user %nice %sys %iowait %irq %soft %steal %idle intr/s 01:04:19 PM all ...
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3answers
524 views

How to calculate the memory consumed by a “C” program in linux

I have written two C programmes one is using function pointer, and the other without function pointer. Now i want to know the memory consumed by the two programmes , to see how memory can ...
5
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1answer
170 views

Whats the history behind the fork bomb?

I have read other questions about its work and other things that Fork bombs operate both by consuming CPU time in the process of forking, and by saturating the operating system's process table. A ...
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0answers
29 views

How do I gather average cpu use in the background?

I'm trying to determine if an issue I'm having is related to cpu use, but my impacted application doesn't allow me to change terminals once it's open. It there a way I could dump only the cpu useage ...
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1answer
42 views

Enable virtualization with gigabyte ud3 990fx

I'm trying to get the virtualization running : I have the following settings: Mainboard: gigabyte ud3 990fx CPU: fx-9590 Kernel: 3.11.0-12-generic Linux Mint 17 In the bios both svm as well as ...
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0answers
102 views

Kill the process and restart server when memory is exceeded - bash and cron

I have a site on webfaction, using django and python. However, I have problem with memory. The problem arises, because I use external library, that can run forever (consuming much time and memory). ...