Nexus 3064 strange CPU utilization

Question

My SNMP monitoring showing Nexus 3064 switch CPU utilization 20%

But on switch cpu history showing 72 Hour maximum CPU%, is this normal?

# show proc cpu history

      1   1 11  1  1  11   111 11   11  1 113 1111       11 1 1
    871886278286168068158793166229780186782967001479786891680938
100
 90
 80
 70
 60
 50
 40                                         #
 30                                         #
 20         #          #     #          #  ##             #
 10 ############################################################
    0....5....1....1....2....2....3....3....4....4....5....5....
              0    5    0    5    0    5    0    5    0    5

               CPU% per second (last 60 seconds)
                      # = average CPU%



    334571515122345235433355611125223523654335661222362353644463
    678637482746907778793807786736447851192360009523617293532312
100
 90
 80
 70     *                   *                             *
 60    **         *  *     **    *   *  **    **     *  * *   *
 50   *** * *     *  **   ***    *   *  **   ***     *  * *   *
 40 ***** * *   *** **** ****    *  **  *** ****    **  * *****
 30 ***** * *  **************    *  ************ *  ************
 20 ******************************************##*****#**#*#***#*
 10 ############################################################
    0....5....1....1....2....2....3....3....4....4....5....5....
              0    5    0    5    0    5    0    5    0    5

               CPU% per minute (last 60 minutes)
              * = maximum CPU%   # = average CPU%



    687777767779768979779898797778977988977777667777886797776777778787777888
    969235992613381786454656352687445460203020996608128502229649807435186873
100                * *    *  *
 90  *         *   * *  **** *   **  ** *               *         *      **
 80  **  **  * *  **** ***** * **** *****       ** *** **    * ** * ** *****
 70 ************************************************************************
 60 ************************************************************************
 50 ************************************************************************
 40 ************************************************************************
 30 ************************************************************************
 20 *#######################################################################
 10 ########################################################################
    0....5....1....1....2....2....3....3....4....4....5....5....6....6....7.
              0    5    0    5    0    5    0    5    0    5    0    5    0

                   CPU% per hour (last 72 hours)
                  * = maximum CPU%   # = average CPU%

proc table

# show processes cpu sort | exclude 0.0


PID    Runtime(ms)  Invoked   uSecs  1Sec    Process
-----  -----------  --------  -----  ------  -----------
12624     61454528  135428515    453   7.00%  t2usd
   27    389745106  316991888   1229   2.00%  ksmd
11310      1311430    553476   2369   1.00%  sensor
11367          113       253    448   1.00%  arp
11371          149       106   1406   1.00%  pktmgr
CPU util  :    4.78% user,    7.97% kernel,   87.23% idle
Please note that only processes from the requested vdc are shown above

Answer 1

If you look at the legend you'll see that the running average is shown at about 20% (the "#" marks) with the asterisks being peak percentages. The CLI graph is really imprecise, but what you're generally seeing is periodic (and very brief) spikes.

Answer 2

The value being represented by SNMP monitoring is a result of the MIB/OID being used when you are polling the device. A better command to use for correlation would be "show system resources" and look for CPU status.

CPU status: CPU usage percentage in user mode, kernel mode, and idle time in the last one second. For a dual-core Supervisor, CPU is averaged across both cores.

It is most likely using OID 1.3.6.1.4.1.9.9.305.1.1.1 which is part of CISCO-SYSTEM-EXT-MIB.