[c-nsp] 6500 netflow export and the switch cpu

[Phil Mayers]

Jon Lewis wrote:
> I've got a 6509 with sup720-3bxl running 12.2(18)SXD7b.  It's forwarding 
> several hundred mbit/s across a number of gig ports on WS-X6416-GBIC cards.

That's an old IOS. You should probably consider an upgrade to the later 
SXF release (e.g. 10, 11, 14)

There are a number of netflow related bugs referenced in the release notes.

> 
> I've noticed it's gotten very slow at certain things (like write mem), 
> and when looking at the switch (remote command switch show proc cpu), I 
> was kind of shocked to see 85% CPU utilization or higher across all time 
> avgs. The biggest CPU eating process seems to be netflow export
> 
>  223  2563111984 126342970      20287 38.27% 42.39% 42.03%   0 NDE - IPV4
> 
> Other than disabling export or moving traffic off this device, are there 
> things I can do to tone this down?  The couple hundred mbit/s this 
> switch is forwarding is supposed to be no big deal for this platform.

It's likely number of flows, rather than bit rate.

What do the following say:

sh mls netflow table-contention detailed
sh mls netflow flowmask
sh mls nde
sh platform hardware capacity netflow