CPU spikes on 3750X stack

[lcaruso]

Hi,

This 3750X stack (3 members) has some 100% cpu spikes. Is this bad enough to start tracking down the cause(s) or is this somewhat typical and not a reason for concern? I just took this reading. How can you detemine when the 100% and 80% spikes occurred? 

Thanks.

    2222233333333332222222222444442222222223333322222222222222
    7777733333333338888888888000007777777770000077777888887777
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)
    4434334343333343363333433333333333433344344334334344443433
    0142910904995509969998084897389864066911800623860800006259
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%
                 1                                                        
    6454455657649044456464745445455555564665444658555464576544846755544447
    6357737676189085447417652469680238316012446614977908055638048329473598
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%

[InayathUlla Sharieff · Accepted solution]

Hi,

The Switches CPU should not reach 80% or 100% in normal circumstances.  It really depends if there is any polling happens from the SNMP server to the Switch that times you see some spike on CPU which is normal after which it automatically get reduced. There are several reason which will cause the CPU to go high and we can only trace down the rootcause during live situation.

Please find below link which will explain what situation the CPU goes high and how you need to troubleshoot it.

http://www.cisco.com/en/US/docs/switches/lan/catalyst3750/software/troubleshooting/cpu_util.html#wp1023843

HTH

Regards

Inayath

*Plz rate if this is helpfull.

[lcaruso]

Thanks for your reply.

Good point about SNMP polling. They do use Solarwinds.

[Leo Laohoo]

What IOS are you using?