Jeff Fitzwater wrote:
We are running 12.2SXH2a on sup720-CXL and have been having
consistently high (80-100%) CPU on route processor when retrieving
either the ARP table or the Bridge-mac table. No matter what program
we use HP NNM or an snmp script, the CPU route process goes from 20%
to 90+% with the SNMP process being the top dog when you do a "sho
proc cpu sort".
How big is your ARP table? We see high-ish CPU usage with >6k entries,
even on SXF. Identically configured routers with ~4k entries see much
lower CPU usage.
There seems to be a non-linear growth in CPU usage for polling (the ARP
table at least). I do have a TAC case open with Cisco (how bad is it
going to be with ~10k entries?) but their response has been... poor.
There's some docs on the Cisco website from days of yore, advising
people to enable CEF, because it provides lexically-sorted data
structures allowing the ipNetToMedia table to be rendered quickly.
Obviously this does not apply to 6500s.
I suspect the 6500s don't store the ARP table in OID-lexical order
internally, and the CPU is having to sort the table every time. I
suspect the same applies to the dot1dTpFdb table.
I have looked at every option on list and at CISCO but nothing
resolves the problem. It appears that internally the route processor
is doing a lot of crunching to get this table data, specifically the
ARP and Bridge Mac table. I remember something about the format it's
in and it had to be converted when retrieved with SNMP.
Q. Does anybody know if there is any change with SXI and SNMP queries?
I also remember reading something about a different way to retrieve
this data locally on the router and push it to a host, but cannot find
any reference to it now. Any ideas on this?
There's some support for bulk data gathering
http://www.cisco.com/en/US/docs/ios/12_0s/feature/guide/gdatacol.html
...however if (as I suspect) the
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