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cathy_123's avatar
cathy_123
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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...
cathy_123's avatar
cathy_123
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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!

Rodrigo_Albuque's avatar
Rodrigo_Albuque
Icon for MVP rankMVP
Jun 06, 2019

ah, yeah. I missed that.. sorry.

 

Are you able to take a snapshot of your system and upload to ihealth? https://ihealth.f5.com

 

You can log in to BIG-IP and click on System --> Support.

 

You can then upload your snapshot (called qkview) to ihealth and lastly copy the ihealth link and paste it to us.

 

I can have a quick look at your CPU usage.

  • Rodrigo_Albuque's avatar
    Rodrigo_Albuque
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    Jun 06, 2019

    Cathy,

     

    I see daemon.log is filled with this:

     

    Jun 3 04:09:13 seatm1lb001 warning init: serial-ttySX (ttyS0) main process (1257) terminated with status 1

    Jun 3 04:09:13 seatm1lb001 warning init: serial-ttySX (ttyS0) main process ended, respawning

    Jun 3 04:09:13 seatm1lb001 warning init: Temporary process spawn error: Cannot allocate memory

    Jun 3 04:09:40 seatm1lb001 warning init: Temporary process spawn error: Cannot allocate memory

    Jun 3 04:15:10 seatm1lb001 warning init: Temporary process spawn error: Cannot allocate memory

     

    This matches this bug here: https://cdn.f5.com/product/bugtracker/ID676705.html

     

    Any system where the console is not hooked up to /dev/sttyS0 (such as all virtual editions) and where the above bug is not fixed, can experience just high disk usage, not CPU.

     

    However, in your case I can see that CPU1 high cpu is caused by system usage and you confirmed that init is eating up cpu cycles so I'd try changing the "respawn" to "off" in /etc/init/serial-ttySX.conf and rebooting the box (make it standby first!)

     

    I also see a specific monitor (iweb-serviceadmin_new-4435) going up and down. It would be good to have a look at what is causing it too or at least temporarily disabling it just in case.

     

    Cheers.

    Rodrigo

     

  • Rodrigo_Albuque's avatar
    Rodrigo_Albuque
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    Jun 06, 2019

    If you haven't rebooted the box yet, could you please collect the output of pmap -x 1 command?

  • cathy_123's avatar
    cathy_123
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    Jun 06, 2019

    Thank you Rodrigo. I will further check and give you an update. Thank you!