The 4300 & 4400 series routers run IOS XE & behave quite differently from previous branch router models (e.g. 2900 or 3900 series). They use dedicated CPU cores to handle forwarding traffic, the 4300 series uses specific cores on the Intel Atom C2000 series CPU & the 4400 series have a dedicated Cavium Octeon series CPU for this purpose. There's separation of the control plane via a dedicated CPU core, with packet forwarding spread across multiple cores. However the IOSd process, which handles the CLI, runs on a separate CPU from the control plane. As a result show process cpu only displays the CPU utilisation by the IOSd process, which will generally be very low. Instead show platform hardware qfp active datapath utilization must be used to see the CPU utilisation by the forwarding CPU(s).
Here is the show process cpu history output of a 4331 router that is handling so much traffic punted to the control plane that it isn't able to process OSPF hellos & keeps dropping OSPF adjacencies:
wanr2#sh proc cpu history
11111
444444444444666664444444444666666666600000777775555566666555
100
90
80
70
60
50
40
30
20
10 ***** *******************************
0....5....1....1....2....2....3....3....4....4....5....5....6
0 5 0 5 0 5 0 5 0 5 0
CPU% per second (last 60 seconds)
1 1 1 1 1
080562778529765604564547466449777678786796886767577678698777
100
90
80
70
60
50
40
30
20
10 ###**#****##***** ** * * ** *****#*****#*##*#****##*##*##
0....5....1....1....2....2....3....3....4....4....5....5....6
0 5 0 5 0 5 0 5 0 5 0
CPU% per minute (last 60 minutes)
* = maximum CPU% # = average CPU%
For comparison, the forwarding CPU(s) are at 100%:
wanr2#sh plat hard qfp act datapath utilization
CPP 0: Subdev 0 5 secs 1 min 5 min 60 min
Input: Priority (pps) 2 2 2 2
(bps) 2744 2056 2072 2064
Non-Priority (pps) 98504 98368 98543 77967
(bps) 48603624 48562944 48578680 38524136
Total (pps) 98506 98370 98545 77969
(bps) 48606368 48565000 48580752 38526200
Output: Priority (pps) 2 3 2 3
(bps) 2704 3240 3152 3096
Non-Priority (pps) 128 125 103 111
(bps) 243736 218816 174288 224744
Total (pps) 130 128 105 114
(bps) 246440 222056 177440 227840
Processing: Load (pct) 100 100 100 79
wanr2#sh processes cpu platform sorted
CPU utilization for five seconds: 4%, one minute: 5%, five minutes: 4%
Core 0: CPU utilization for five seconds: 8%, one minute: 4%, five minutes: 3%
Core 1: CPU utilization for five seconds: 24%, one minute: 7%, five minutes: 4%
Core 2: CPU utilization for five seconds: 4%, one minute: 4%, five minutes: 3%
Core 3: CPU utilization for five seconds: 3%, one minute: 4%, five minutes: 4%
Core 4: CPU utilization for five seconds: 8%, one minute: 7%, five minutes: 7%
Core 5: CPU utilization for five seconds: 1%, one minute: 0%, five minutes: 0%
Core 6: CPU utilization for five seconds: 14%, one minute: 12%, five minutes: 11%
Core 7: CPU utilization for five seconds: 0%, one minute: 0%, five minutes: 0%
Note that these router platforms also have an optional higher throughput license, which unlocks more CPU cores for forwarding. If this feature has been licensed, it is enabled via the platform hardware throughput level command, which requires a reboot:
wanr2(config)#plat hardware throughput level ?
100000 throughput in kbps
300000 throughput in kbps
wanr2(config)#platform hardware throughput level 300000
Feature Name:throughput
PLEASE READ THE FOLLOWING TERMS CAREFULLY. INSTALLING THE LICENSE OR
LICENSE KEY PROVIDED FOR ANY CISCO PRODUCT FEATURE OR USING SUCH
PRODUCT FEATURE CONSTITUTES YOUR FULL ACCEPTANCE OF THE FOLLOWING
TERMS. YOU MUST NOT PROCEED FURTHER IF YOU ARE NOT WILLING TO BE BOUND
BY ALL THE TERMS SET FORTH HEREIN.
Use of this product feature requires an additional license from Cisco,
together with an additional payment. You may use this product feature
on an evaluation basis, without payment to Cisco, for 60 days. Your use
of the product, including during the 60 day evaluation period, is
subject to the Cisco end user license agreement
http://www.cisco.com/en/US/docs/general/warranty/English/EU1KEN_.html
If you use the product feature beyond the 60 day evaluation period, you
must submit the appropriate payment to Cisco for the license. After the
60 day evaluation period, your use of the product feature will be
governed solely by the Cisco end user license agreement (link above),
together with any supplements relating to such product feature. The
above applies even if the evaluation license is not automatically
terminated and you do not receive any notice of the expiration of the
evaluation period. It is your responsibility to determine when the
evaluation period is complete and you are required to make payment to
Cisco for your use of the product feature beyond the evaluation period.
Your acceptance of this agreement for the software features on one
product shall be deemed your acceptance with respect to all such
software on all Cisco products you purchase which includes the same
software. (The foregoing notwithstanding, you must purchase a license
for each software feature you use past the 60 days evaluation period,
so that if you enable a software feature on 1000 devices, you must
purchase 1000 licenses for use past the 60 day evaluation period.)
Activation of the software command line interface will be evidence of
your acceptance of this agreement.
ACCEPT? (yes/[no]): yes
% The config will take effect on next reboot
The current throughput level can be confirmed via show platform hardware throughput level:
wanr2#show plat hard throughput level
The current throughput level is 100000 kb/s
Further useful information can be found here:
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