CPU utilisation

Unanswered Question
Apr 1st, 2002
User Badges:

Hi ,

What should be the ideal CPU utilisation for a 3640 router with 128 MB main memmroy and 16 MB flash?

The output of sh process cpu is

CPU utilization for five seconds: 50%/16%; one minute: 35%; five minutes: 32%

Which utilisation should one be lloking for five sec,one mon or five min..is the utilisation on my router with in limits??

My router has a few IPsec VPN terminated along with two T1 circuits.

Thanks and regards,


  • 1
  • 2
  • 3
  • 4
  • 5
Overall Rating: 0 (0 ratings)
tvanderwerken Mon, 04/01/2002 - 06:47
User Badges:

What does the rest of that command output look like? Which process is causing this?

jimmy.joseph Mon, 04/01/2002 - 09:06
User Badges:


The processess consuming the CPU are

CPU utilization for five seconds: 39%/11%; one minute: 55%; five minutes: 53%

PID Runtime(ms) Invoked uSecs 5Sec 1Min 5Min TTY Process

30 81099912 147061877 551 7.20% 8.61% 7.16% 0 IP Input

77 210203360 111630960 1883 29.53% 29.88% 28.61% 0 Encrypt Proc

As i had mentioned earlier..i have a couple of GRE and Ipsec VPNs on this router which are eating many resources.



bhedlund Mon, 04/01/2002 - 10:53
User Badges:
  • Silver, 250 points or more

Sounds like you have answered your own question.

VPN hardware acceleration products are available for the 3600 series router to lighten the load on your CPU signifigantly.

Also, use 'show interface stat' to ensure your router is using the best switching path to move your other non-VPN packets between interfaces.

jimmy.joseph Mon, 04/01/2002 - 10:57
User Badges:


I know that the main reason for my router CPU utilisation is VPNs but what i would like to know is

1. Can i consider an average utilisation of 45% as normal

2. What should be the ideal utilisation for this router

3. Is there any document or URL available regarding this



ruwhite Mon, 04/01/2002 - 16:03
User Badges:
  • Gold, 750 points or more

There are no doc's or url's available for this--it's a matter of what you're comfortable with. It sounds like the router is running normally, with encryption taking up most of the run time at process level, and a moderate interrupt level.

The critical thing is to develop a basline and look for changes.



This Discussion