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New Member

C3500XL CPUHOG problems


I have been recently getting this message on my Catalyst 3524 XL PWR (running IOS 12.0(5)WC9):

00:01:111669149696: %SYS-3-CPUHOG: Task ran for 2098 msec (203/192), process = STP Queue Handler, PC = 1D9550.

-Traceback= 1D9554 27FCF4 1E9410

I can't seem to get rid of it.. The STP queue handler on these switches is running at about 10% all the time. Is this normal?

The switches are pretty much loaded full with IP phones (a mix of 7960s and 40s) with computers downstream.

This happens on two of my switches in exactly the same way.

I am looking at this CPUHOG message as the cause of poor IP phone performance because of poor switch performance?

Thanks in advance!~


Re: C3500XL CPUHOG problems


I remember similar problem a month ago:

Cat2940 loosing free memory, CPUHOG syslog messages, switch restarted finally.

The reason was CDP memory consuming bug in IOS 12.1(19)EA1.

12.0(5)WC9 is the latest IOS so there might be a new bug in it (but Cat3500XL family is EOL with PWR models exception, so no new features should be added).

I'd try to check free memory amount on the switch by sh mem command, compare it to other switches in your network and check if it is not decreasing constantly.



New Member

Re: C3500XL CPUHOG problems

Thanks for the suggestion.. I am running the PWR model - I did upgrade to WC9 within 2 weeks when it came out - but I didn't have this kind of problem until now (WC9 was deployed 3 weeks ago)

Heres the output of the sh mem on an unaffected switch:

Head Total(b) Used(b) Free(b) Lowest(b) Largest(b)

Processor 4D0F34 3338444 2854528 483916 384668 451532

I/O 70000000 1048576 619792 428784 321640 417160

Then here's the output of an affected switch:

Head Total(b) Used(b) Free(b) Lowest(b) Largest(b)

Processor 4D0F34 3338444 2859892 478552 379204 373252

I/O 70000000 1048576 600040 448536 321640 377952

Not a huge difference unfortunately, and the affected switch free memory does not seem to decrease consistantly - but i'll check this tomorrow.

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