Re: High interrupt cpu usage on 7206...

Well, it seems that it's just that my expectations on the capacity of
the box were above the real power of it.
I ended up removing all the NBAR classification and we are back in
business (CPU on 20-25% for ~50Mbps).

In the process, I learned something about the new 15.x CEF
implementation: PBR default NH was not supported by CEF before,
so default PBR (default route) flows were punted to the RP.
Now it is, but with a requirement that was not there:
NH has to be real NH, i.e., it will not be recursivelly determined.
(recursive worked before, now its optional for specific routes)

The problem with that is that it creates a single point of failure. If
the NH goes down, your PBR creates a black hole.
So I used to use "recursive" NH with a static route that was tracked.
No joy in 15.x, so I went back to 12.4.

Thanks for tunning :)
-Carlos

Carlos G Mendioroz @ 23/07/2014 10:56 -0300 dixit:
> Andrew,
> thanks. As most of the CPU is being chewed at interrupt time, there is
> no process in the process list that has any significant portion of it.
>
> That document (and many others) redirect to
>
> http://www.cisco.com/c/en/us/support/docs/routers/7500-series-routers/41120-highcpu-interrupts.html
>
> Which I'm starting to memorize already :-/
>
> -Carlos
>
> Andrew LaPorte @ 23/07/2014 10:51 -0300 dixit:
>> Carlos,
>>
>> I typical start out with a " show proc cpu" or " show proc cpu sorted" to
>> figure out which process is eating up the cpu. I then normally try to
>> figure out what the process is responsible for.
>>
>> Here is a doc that may help:
>> http://www.cisco.com/c/en/us/support/docs/routers/10000-series-routers/15095
>> -highcpu.html?referring_site=bodynav
>>
>> I know it is not specific to the 7200 but it's a good read.
>>
>> Andy
>>
>> -----Original Message-----
>> From: nobody_at_groupstudy.com [mailto:nobody_at_groupstudy.com] On Behalf Of
>> Carlos G Mendioroz
>> Sent: Wednesday, July 23, 2014 9:27 AM
>> To: Cisco certification
>> Subject: OT: High interrupt cpu usage on 7206...
>>
>> is driving me nuts :(
>>
>> I'm trying to nail down what is taking a 7206 with G1 to its knees with just
>> about 50Mbps (75%/72% cpu).
>>
>> The config has many things, like WCCP, QoS, PBR, NBAR and OSPF + BGP, but
>> still, 50Mbps for a G1 should be a breeze, shouldn't it ?
>>
>> I'm seeing some SPD flushes, trying to make sense of them.
>> But I would not mind advice on what to look after.
>> (I was hoping CSCtg42179 would save my day, but upgraded to 12.4.24T8 and
>> same thing...)
>>
>> TIA,
>> --
>> Carlos G Mendioroz <tron_at_huapi.ba.ar> LW7 EQI Argentina
>>
>>
>> Blogs and organic groups at http://www.ccie.net
>>
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>>
>>
>>
>>
>>
>

-- 
Carlos G Mendioroz  <tron_at_huapi.ba.ar>  LW7 EQI  Argentina
Blogs and organic groups at http://www.ccie.net