I have a Dell Inspiron 7520 with an Intel Core i7-3612QM CPU that repeatedly cycles through 100% usage of each individual core while barely using any other core as shown in the screen shot below.

CPU Usage Snapshot

This happens regardless of what I'm running and might be what's causing my laptop to heat up, how would I go about making my laptop use all of the cores concurrently?

I'm using Ubuntu 14.04 LTS

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    It will help if you tell us what version of the OS you are using (report uname -a) and what application you are running. – Charles Green Jan 10 '16 at 15:19
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    I'd also recommend running the stress utility sudo apt-get install stress then the command stress --cpu 8 --io 4 --vm 2 --vm-bytes 128M --timeout 20s while running your system monitor. – Charles Green Jan 10 '16 at 15:24
  • I copied that set of instructions and all my CPU's even out at 90-100% before going back to 1 of them being at 100%, could you give me more info on what is that command does? – Oyibo Jan 10 '16 at 16:13
  • The command creates several threads, each of which is assigned a task (endlessly running square roots, for example is the CPU task) man stress will give you lots of information about the program. It appears then that your OS and computer run correctly (stress causes all the processors to top out) but you ave a program which is not operating on all processors. Use of the program top will tell you what program is eating all of the CPU time on the single processor. – Charles Green Jan 10 '16 at 16:18

It's not possible to spread a single threaded processes over multiple cores evenly. A single threaded process can only run on one core at a given time and the kernel might move the process/thread to another core while the programm runs. If one process is running at 100% on one core all the time you should check for that process and why it is utilizing one core.

  • Thank you for your answer, how would I go about checking exactly what process is using a specific core? I've got this recurrently though which is why I feel it's a system and not a process-specific issue if that makes sense – Oyibo Jan 10 '16 at 16:07
  • To check which process is running at 100%, I would recommend htop or top. Depending on that, maybe something is running that does not need to run or could also indicate a misconfiguration. For top you also could use top -n1 for a one shot output. – Thomas Jan 10 '16 at 16:17

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