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cathy_123's avatar
cathy_123
Icon for Cirrus rankCirrus
Jun 06, 2019

High CPU Utilization CPU1

Hello F5!

Would like to ask for possible cause and fix. We have high CPU utlization on CPU1 . It seems it is the systems causing our CPU1 high utilization. Our F5 is in Virtual and in version 12.1.2. Thank you!

CPU: 0 (clock ticks)  Last 5 sec Last 1 min Last 5 min  Total
 -                    (avg/sec)  (avg/sec)  (avg/sec)      -
 User                         8          3          2  26.7M
 Niced                        0          0          0   3.9M
 System                      58         13          3  17.3M
 Idle                        33         83         94   2.7G
 Irq                          0          0          0   8.5K
 Softirq                      0          0          0   2.0M
 Iowait                       0          0          0   2.0M
 Stolen                       0          0          0      0
 Util% (last 10 sec)          -          -          -      0

CPU: 1 (clock ticks)  Last 5 sec Last 1 min Last 5 min  Total
 -                    (avg/sec)  (avg/sec)  (avg/sec)      -
 User                         5          2          1  28.3M
 Niced                        0          0          0   6.5M
 System                      30          4          1  45.6M
 Idle                        63         94         97   2.7G
 Irq                          0          0          0    582
 Softirq                      0          0          0 501.0K
 Iowait                       0          0          0   2.5M
 Stolen                       0          0          0      0
 Util% (last 10 sec)          -          -          -    100
  • Hamish's avatar
    Hamish
    Icon for Cirrocumulus rankCirrocumulus

    Have a look and see which process is using all that CPU...

     

    'top' may help there...

     

    H

  • Hi Cathy

     

    There is no high CPU utilisation from the output you posted.

     

    The Idle output is just how much of its time the CPU was just sitting there doing nothing.

     

    The System output average for the past 5 minutes for CPU 1 was just 1%.

     

    The rest is all zeroes.

  • Thanks Everyone!

     

    Hi Hamish I did try top command see below

     

    Swap: 1023996k total,  782240k used,  241756k free,  262580k cached

     

     PID USER   PR NI VIRT RES SHR S %CPU %MEM  TIME+ COMMAND                                                                                          

      1 root   20  0 598m 188m 1140 R 96.6 4.8  8122:08 init . -> init has 96% utilization                                                                                            

    10580 root   RT  0 2790m 71m 52m S 3.9 1.8  6555:32 tmm.0                                                                                           

      9 root   20  0   0  0  0 S 2.0 0.0 74:45.46 ksoftirqd/1                                                                                        

     5796 root   20  0 44756 17m 15m S 2.0 0.5  1427:46 bigd             

     

    Hi Rodrigo,

     

    Would like to ask isnt the CPU0 has 0% Util and CPU1 has 100% Util?

     

    Thank you!

  • Hamish's avatar
    Hamish
    Icon for Cirrocumulus rankCirrocumulus

    96% utilisation for init isn't normal.

     

    It's a centos (i.e. RedHat) base. (Not sure which one for 12.1.2 - But my v24 uses Centos 6.8).

     

    However it shouldn't normally use a lot of CPU. Anything logged? (/var/adm/messages) or in the 'dmesg' output?

     

    Have you edited inittab at all? Normally there's just a single entry in there, but some people (Myself also) like to put important daemons in there with restart enabled. Breaking those can cause init to spin.

     

    I take it from the discrepenecy between your tmmsh cpu output and top that it's bursty?

     

     

    H

     

    • cathy_123's avatar
      cathy_123
      Icon for Cirrus rankCirrus

      Hi Hamish,

       

      I surely didnt change it.. I am seeing messages on dmesg but I am not really sure about it.

       

      • Hamish's avatar
        Hamish
        Icon for Cirrocumulus rankCirrocumulus

        So what are the messages you're seeing? Nobody can help much without the info...