cpulimit rocks
| August 22nd, 2008I just read about the CPUlimit program in the news section of the GNS3 website, i really had no idea about such a thing, immediately downloaded it , compiled it and it rocks. this is just amazing, first of all this is immediately going into my script for dynamips and the next version of the live cd, which should be ready by the 10th of the next month ( hint: there could be a version rangin between 10-20 mb) , als0 i just finished making it as a package for slitaz. Have sent it to the mailing list. Once they accept it, ill also put it up for download on this site. [[ it got accepted ]] download the slitaz package for cpulimit here . Download it and do a tazpkg install, thats it.
Now i tested it by setting the limit to 40% with the following command
cpulimit -e /usr/bin/dynamips -l 40
and then started 4 routers with my script without any conf and no idlepc value, the bootup ran a little slow but im able to do basic show run’s . Im not sure how useful this will be, but further tests will include running full labs on 70 percent and checking out what happens.
Now the cool thing is if you have 2 cpus in your machine , it means you set the command like this
cpulimit -e /usr/bin/dynamips -l 150
what the above command means is your setting the process limit for dynamips at 150 % since 200% now defines your cpu. so if you have 4 cpus your range goes to 400%.
[[ note: you need the development version for the above feature ]]
For all you guys checking out dynamips / dynagen /GNS3 for your cisco preparations you definitely need this, download it at http://cpulimit.sourceforge.net
Can you make an image with Internetwork expert topology (which is public domain) and dynagen and dynamips installed. So that all someone has to do is to put in the right IOS images in the correct folder and it is up and running. If you have the exact same images as in the configuration files for CCIE SP .net configuration file you will not even have to change the folder or file name in the .net configuration file. That will be the closest automation and will be helpful for many of us who are not linux savvy.
Thanks again for all the great work.
VEE
hi , veetee ,if you can you send me the net files along with the initial configs , ill make it for you. and keep coming up with the ideas, i havent forgotten your vmplayer idea yet, just that havent rebooted into windows for so long now.
http://www.internetworkexpert.com/downloads/internetwork.expert.topologies.zip
This is the URL for internetwork expert topologies. This is off the page which has a Dynamips tutorial from internetwork expert.
http://www.internetworkexpert.com/resources/iosonpc.htm
Thanks for the good work you are doing.
VEETEE
Hi,
I’m running Ubuntu 8.10 on dual core amd-64 system with 4 Gig RAM. Only running 9 routers, using real switches. However I never noticed that both CPU’s get pegged at 100% when Dynagen gets launched. I don’t use the system for anything but CCIE preparation. Failed lab in December, but when I was doing full labs before I was using 4 routers as switches (13 total) now only running 9. Question after my long winded setup, is will I still need cpulimit for 9 routers, if I don’t use the box for anything else? In the past when I would get to the end of my labs, I would loose EIGRP adjanceies, pings would drop etc. Thanks!
Hi James,
You say that both cpu’s get pegged at 100% when dynagen gets launched, that would usually happen when either idlepc settings are incorrect or not present, is that the case? . also what i have noticed that its a good idea to give it a fresh run of idlepc values everytime you restart your pc or a different lab.
I dont think you would need cpulimit, i have a dual core laptop with 2.5 gig ram, and it has run cool. cpulimit is useful only so that your pc has enough processing power to do your other work. like, if you setup your limit on dynamips to 150% ( since you have dual core) , the dynamips process will not go above 150% of cpu utilisation, but the labs will become slow.
hope i understood your question correctly.
and best of luck for your exams.