GNS3/Dynamips performance

Hi all,

I was going to do some experimenting on routing traffic different ways while benchmarking performance. I get very low performance when performance testing links in GNS3. iperf shows about 1,3 Mbps tops regardless of link type and generated traffic (tcp/udp, window size, parallell streams etc), even in a very simple topology with two routers. The host machine is a Retina i7 macbook pro with 16 GB RAM, the load on the machine is piratically zero. VirtualBox guests is a clean, tiny debian install. Tried on Windows 7 as well, no better luck there.

Anyone out there who care to share some iperf benchmarking results, in GNS3, so I have something to compare with?

Thanks.

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Comments

Heero

That sounds about right. GNS3 is not high performance...which you can easily tell. However, it doesn't have to be high performance to do what it does.

networker050184

That really isn't a test you should be trying to do with GNS3 if you are looking for real world results.

ecce

Allright, thanks for your replies. I didn't expect superior performance, but I was surprised it was that low. I was hoping to make a point in class (work as academy instructor) about different routing protocols being clever when choosing a route.

ampdeck

I find GNS3 to be running slow when using macbook, Im using Retina i7 16gb 2.7ghz.

siggnation

Not sure if you have already tried, but ensure you click the Idle pc finder option when installing the router rom; it should calibrate to not use as much cpu compared to not having enabled that option.

ampdeck

siggnation wrote: »

Not sure if you have already tried, but ensure you click the Idle pc finder option when installing the router rom; it should calibrate to not use as much cpu compared to not having enabled that option.

sorry I forgot to mention that I always include idlepc and idlemax to my GNS3 topologies, but still I find its very slow when using macbook compared to windows.

Heero

You won't get much, but you don't need it from GNS3 either. It is NOT a performance testing tool. It is basically a tool that gives you free access to fully emulated Cisco Routers at the explicit expense of performance.