Monday, December 6, 2010

How to minimize CPU utilization when using Dynamips/GNS3 (idlepc + idlemax)

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  1. It's very usefull, this should be in doc in GNS3. I was close to buy new laptop, but idlemax helped me. Thank you.

  2. hey Brother could u pls tell me how to set idlemax
    in Gns3 i search but didn't get any option pls let me know

  3. Hey Praveen,

    Just look at the .net file created by the GNS3 and add the idlemax line.

  4. Hi..

    i have just installed the gns3 and when i started a router my cpu usage reached to 100%, as above mentioned comments we need to change ildemax in .net file but where i can find this file.??

  5. Can some one help me out? i tried to follow this yet my CPU spiked 100%. below is the idlemax value i added yet no difference.

    autostart = False
    workingdir = C:\DOCUME~1\Karmesh\LOCALS~1\Temp
    udp = 10000
    image = G:\LABS\IOS\c3640-ik9s-mz.124-25b.bin
    idlepc = 0x60696f6c
    idlemax = 100
    sparsemem = True

  6. @saha,

    idlepc is IOS specific.. to get the proper idlepc 1.)Load a single router on the GNS3
    2.)Power it up
    3.)Console to the router
    4.)get into privilege mode
    5.)right click into the router and select idlepc calculation
    6.)choose the value with *.

    i hope this could help..

  7. Thanks for this. Dropped my CPU 70%!


  8. Worked on Ubuntu 10.10 by the way

  9. Thanks man. I was almost going to buy a new labtop too. Idlemax makes perfect. you're genious

  10. good one
    ....people like you save the world

    1. There is now a much better that the Dynamips that the IOU but the only problem it is only for Cisco internal use.. hopefully they could provide one for FREE....

      some say you could run the whole INE topology on an ATOM machine..

  11. i am using 3725 n 3640 series routers in my topology.
    i added idlemax = 100 in the .net file, but still the usage is 100%.i calculated idlepc too.
    pls help me out i m nt able to carry out my lab practice.

  12. Thank you, idlemax = 100 works great.

  13. This is a Miracle.. I have 20 routers and my pc was amazing... completely speechless.. this is a life saver...