High CPU on 6509 but no interrupts

[arisgr0]

Hello,

Any ideas why we have high CPU but no high processes? I am aware only of the case where you have high CPU due to interrupts, but i suppose this is not the case

switch#show process cpu sorted | ex 0.0
CPU utilization for five seconds: 98%/2%; one minute: 50%; five minutes: 30%
PID Runtime(ms) Invoked uSecs 5Sec 1Min 5Min TTY Process
331 29739004 244487388 121 2.71% 1.34% 0.75% 0 IP Input
23 3738787721795502101 208 1.59% 1.32% 1.21% 0 ARP Input
555 756276668 823695966 918 1.51% 1.42% 1.47% 0 Port manager per
385 7086924 38885393 182 1.35% 0.66% 0.35% 0 HTTP CORE
49 2491801642485843878 0 0.79% 0.72% 0.67% 0 ARP Snoop
323 105436 344809356 0 0.23% 0.40% 0.45% 0 IP SLAs Responde
290 5988043098764868 0 0.15% 0.15% 0.15% 0 Ethernet Msec Ti

[Leo Laohoo]

See if you've got interfaces that have incrementing Total Output Drops.

[arisgr0]

The problem has stopped so I cannot see something at the moment (no increase in drops seen now). It lasted for about 10 minutes.

I will keep that in mind whenever that happens.

Any more clarifications on this one? Or any other thoughts?

Thank you

[Georg Pauwen]

Hello,

anything that is punted to the CPU for processing can cause this (such as access lists that use logging). If possible, post the full running configuration of your 6509,maybe we can spot something...

[arisgr0]

The config is similar to other 6509 devices of our network. There are some ACEs with log keyword but no matches.

It strikes me though that you mention ACL logging. This should translate to high CPU due to interrupt. This is not the case according to the show command. Correct?

[Georg Pauwen]

Hello,

the interrupts don't show up in the process statistics.

[arisgr0]

The second percentage figure (2%) denotes the CPU used in interrupt level.

That is why I am quite confused about the cause of the high CPU