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Steve_Brockman_'s avatar
Steve_Brockman_
Icon for Nimbostratus rankNimbostratus
Oct 10, 2005

CPU Usage on LTM

Does anyone know why the CPU of the BIG-IP might be showing a constant 95%+ if one SSH's into the box and monitors via "top" ??
  • patrick_osewal2's avatar
    patrick_osewal2
    Historic F5 Account
    In previous versions of BIG-IP, the majority of the traffic was processed by the system kernel. Starting in version 9.0, the Traffic Management Microkernel, or tmm, processes the traffic. This change causes UNIX command utilities, such as top and ps, to inaccurately report CPU utilization at approximately 80% utilization for single processor systems and 99% on dual processor systems, regardless of the actual system load.

     

     

    For this reason, you should not use UNIX utilities to monitor CPU utilization.

     

     

    For an accurate depiction of tmm CPU utilization, click Performance from the Main tab of the BIG-IP Configuration utility or use the bigtop utility. This is a command that provides statistical monitoring, and displays connections and throughput.

     

     

    http://tech.f5.com/home/bigip-next/manuals/bigip9_0/bigip9_0cli/BIG_IP9_0XCLIGuide2-4-1.htmlwp1158979

     

     

    Best regards,

     

    Patrick