[c-nsp] high cpu usage due to interrupts
Church, Chuck
cchurch at multimax.com
Tue Feb 13 10:39:15 EST 2007
You know, you can find an RSP-2 on EBAY right now for $30. That would certainly help things.
Chuck
-----Original Message-----
From: cisco-nsp-bounces at puck.nether.net [mailto:cisco-nsp-bounces at puck.nether.net] On Behalf Of ulisses
Sent: Tuesday, February 13, 2007 10:08 AM
To: Rodney Dunn
Cc: cisco-nsp at puck.nether.net
Subject: Re: [c-nsp] high cpu usage due to interrupts
Hi Rodney
On 2007-02-13 08:52:27, Rodney Dunn wrote:
> It's an RSP1 and the latest today is an RSP16.
heh :-)
didn't take that into account:
End-of-Life Announcement: September 24, 1999
but is the load of 60000 pps a high load? for this hardware?
> What you need to look at is the pps being switched through
> the box as well as the features you have enabled.
This is Cisco 7505, it seems that the backplane can handle 1.067 Gbps,
and 1.1 Mpps, I suposse that also depends on the RSP...
The information I found didn't mention to which RSP this information
refers to.
When not loaded, it is ~31000 packets/sec in 5 min average [2],
If I scale this by 2 it becomes around 60000 pps, not a lot isn't it?
it seems there is a lot of margin...
> The CPU level there is probably normal for that processor.
>
> If your VIPs have enough memory you could 'ip cef distributed'.
'ip cef distributed' is not an option completed by pressing the
key '?' (only accounting option is shown, anyway i have entered it
and the output of the "show ip interfaces | include switch" is
the same output and the ratio of high cpu interrupts has not changed.
What I find extrange is that all percentage of the cpu usage goes
to interrupts:
Addionally (I haven't mentioned previously) is that when multicast
comes in (around 10-15 Mbps) the cpu burns at 100%. But first
I wanted to make clear that there is no problem with unicast traffic.
Thanks so much for your comments
regards
Ulisses
[2]
# show interfaces | include packets/sec
5 minute input rate 62946000 bits/sec, 8537 packets/sec
5 minute output rate 27570000 bits/sec, 7036 packets/sec
5 minute input rate 3234000 bits/sec, 1041 packets/sec
5 minute output rate 10653000 bits/sec, 1287 packets/sec
5 minute input rate 23616000 bits/sec, 5363 packets/sec
5 minute output rate 37962000 bits/sec, 5599 packets/sec
5 minute input rate 414000 bits/sec, 82 packets/sec
5 minute output rate 329000 bits/sec, 76 packets/sec
5 minute input rate 594000 bits/sec, 612 packets/sec
5 minute output rate 14166000 bits/sec, 1571 packets/sec
5 minute input rate 0 bits/sec, 0 packets/sec
5 minute output rate 0 bits/sec, 0 packets/sec
5 minute input rate 0 bits/sec, 0 packets/sec
5 minute output rate 324000 bits/sec, 76 packets/sec
>
>
> Rodney
>
> On Tue, Feb 13, 2007 at 02:41:51PM +0100, ulisses wrote:
> >
> > Hi all
> >
> > I have followed the guidelines
> >
> > http://www.cisco.com/en/US/products/hw/routers/ps359/products_tech_note09186a00801c2af0.shtml
> > http://www.cisco.com/en/US/products/hw/routers/ps133/products_tech_note09186a00800a70f2.shtml#high_cpu
> >
> > trying to find why I have a high cpu usage due to interrupts
> > but I could not solve it, next I show diagnostics when only routing
> > unicast traffic.
> >
> > The basic configuration of the system (Cisco 7500) is:
> >
> > IOS (tm) RSP Software (RSP-JSV-M), Version 12.1(14), RELEASE SOFTWARE (fc1)
> > cisco RSP1 (R4600) processor with 65536K/2072K bytes of memory.
> > R4600 CPU at 100Mhz, Implementation 32, Rev 2.0
> > 2 AIP controllers (2 ATM).
> > 2 VIP2 controllers (3 FastEthernet).
> > 3 FastEthernet/IEEE 802.3 interface(s)
> > 2 ATM network interface(s)
> >
> > This is the load of the router:
> >
> > EB-LasPalmas1#show interfaces | include is up|load
> > ATM0/0 is up, line protocol is up
> > reliability 255/255, txload 55/255, rxload 152/255
> > ATM0/0.1 is up, line protocol is up
> > reliability 255/255, txload 55/255, rxload 152/255
> > FastEthernet1/0/0 is up, line protocol is up
> > reliability 255/255, txload 82/255, rxload 16/255
> > FastEthernet2/0/0 is up, line protocol is up
> > reliability 255/255, txload 119/255, rxload 68/255
> > FastEthernet3/0/0 is up, line protocol is up
> > reliability 255/255, txload 1/255, rxload 1/255
> > FastEthernet3/1/0 is up, line protocol is up
> > reliability 255/255, txload 35/255, rxload 1/255
> >
> > This is the load near the peak load of the router. I also haven't
> > seen any throttle in the interfaces.
> >
> > I think it is not too much, isn't it?
> >
> > I have enabled all possible swithing options possible, see [1] at the end
> >
> > I also have verified that there are no cache misses in the switching path
> > and traffic uses the supossed switched path with show interfaces stats.
> >
> > The cpu load is 100% (47 of 48%) caused by interrupts:
> >
> > EB-LasPalmas1#show process cpu | include CPU|PID|Input
> > CPU utilization for five seconds: 48%/47%; one minute: 45%; five minutes: 44%
> > PID Runtime(ms) Invoked uSecs 5Sec 1Min 5Min TTY Process
> > 13 176 1809 97 0.00% 0.00% 0.00% 0 ARP Input
> > 40 7036 105293 66 0.00% 0.00% 0.00% 0 ATM OAM Input
> > 44 6572080 1952147 3366 0.08% 0.09% 0.11% 0 IP Input
> > 50 0 2 0 0.00% 0.00% 0.00% 0 SSCOP Input
> > 56 0 2 0 0.00% 0.00% 0.00% 0 ILMI Input
> > 64 0 2 0 0.00% 0.00% 0.00% 0 ATMSIG Input
> > 69 0 1 0 0.00% 0.00% 0.00% 0 Probe Input
> > 70 0 1 0 0.00% 0.00% 0.00% 0 RARP Input
> > 78 0 2 0 0.00% 0.00% 0.00% 0 SPX Input
> > 83 964 926 1041 0.00% 0.00% 0.00% 0 Tag Input
> > 87 0 1 0 0.00% 0.00% 0.00% 0 Net Input
> > 100 7536 39990 188 0.00% 0.00% 0.00% 0 CLNS Input
> > 102 28504 109557 260 0.00% 0.02% 0.00% 0 IGMP Input
> >
> >
> > Following the guideline on high cpu usage cause interrupts I found that:
> >
> > Possible Causes of High CPU Utilization Due to Interrupts
> > Inappropriate Switching Path ---------- Not likely IMHO
> > CPU Performing Alignment Corrections -- No (verified)
> > Router Overloaded with Traffic -------- No (verified)
> > Software Bug -------------------------- I don't know (no access to Cisco TACS)
> > Voice Ports Configured on the Router -- No
> > Active Asynchronous Transfer Mode (ATM) Interfaces on the Router
> > --------------------------------------- No (only the required ones)
> > Many Parallel Express Forwarding (PXF) Punts to the RP
> > -------------------------------------- No
> >
> > so I don't know what to check next... Any comment or suggestion?
> >
> > Thanks so much in advance
> >
> > Ulisses
> >
> >
> > [1]
> >
> > EB-LasPalmas1#show ip interface | include is up|switch
> > ATM0/0 is up, line protocol is up
> > ATM0/0.1 is up, line protocol is up
> > IP fast switching is enabled
> > IP fast switching on the same interface is disabled
> > IP Flow switching is enabled
> > IP CEF switching is enabled
> > IP Flow switching turbo vector
> > IP Flow CEF switching turbo vector
> > IP multicast fast switching is enabled
> > IP multicast distributed fast switching is disabled
> > FastEthernet1/0/0 is up, line protocol is up
> > IP fast switching is enabled
> > IP fast switching on the same interface is disabled
> > IP Flow switching is enabled
> > IP CEF switching is enabled
> > IP Distributed switching is enabled
> > IP Flow switching turbo vector
> > IP Flow CEF switching turbo vector
> > IP multicast fast switching is enabled
> > IP multicast distributed fast switching is enabled
> > FastEthernet2/0/0 is up, line protocol is up
> > IP fast switching is enabled
> > IP fast switching on the same interface is disabled
> > IP Flow switching is enabled
> > IP CEF switching is enabled
> > IP Distributed switching is enabled
> > IP Flow switching turbo vector
> > IP Flow CEF switching turbo vector
> > IP multicast fast switching is enabled
> > IP multicast distributed fast switching is enabled
> > FastEthernet3/0/0 is up, line protocol is up
> > IP fast switching is enabled
> > IP fast switching on the same interface is disabled
> > IP Flow switching is enabled
> > IP CEF switching is enabled
> > IP Distributed switching is enabled
> > IP Flow switching turbo vector
> > IP Flow CEF switching turbo vector
> > IP multicast fast switching is enabled
> > IP multicast distributed fast switching is enabled
> > FastEthernet3/1/0 is up, line protocol is up
> > IP fast switching is enabled
> > IP fast switching on the same interface is disabled
> > IP Flow switching is enabled
> > IP CEF switching is enabled
> > IP Distributed switching is enabled
> > IP Flow switching turbo vector
> > IP Flow CEF switching turbo vector
> > IP multicast fast switching is enabled
> > IP multicast distributed fast switching is enabled
> >
> > --
> > _______________________________ __ ___________________________________
> > /_/
> > Network Operation Center __ __ Email: noc at rediris.es
> > RedIRIS/Red.es /_/ RedIRIS /_/
> > Edificio Bronce __ Tel: + 34 912127625
> > Pza. Manuel Gómez Moreno, s/n /_/ Urgencias: + 34 629148201
> > E-28020 Madrid Fax: + 34 915568864
> >
> > _________________ Spanish Academic & Research Network _______________________
> > _______________________________________________
> > cisco-nsp mailing list cisco-nsp at puck.nether.net
> > https://puck.nether.net/mailman/listinfo/cisco-nsp
> > archive at http://puck.nether.net/pipermail/cisco-nsp/
>
--
_______________________________ __ ___________________________________
/_/
Network Operation Center __ __ Email: noc at rediris.es
RedIRIS/Red.es /_/ RedIRIS /_/
Edificio Bronce __ Tel: + 34 912127625
Pza. Manuel Gómez Moreno, s/n /_/ Urgencias: + 34 629148201
E-28020 Madrid Fax: + 34 915568864
_________________ Spanish Academic & Research Network _______________________
_______________________________________________
cisco-nsp mailing list cisco-nsp at puck.nether.net
https://puck.nether.net/mailman/listinfo/cisco-nsp
archive at http://puck.nether.net/pipermail/cisco-nsp/
More information about the cisco-nsp
mailing list