Auteur Sujet: Question about iPerf -n  (Lu 910 fois)

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aa657

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Question about iPerf -n
« le: 28 avril 2016 à 15:37:48 »
Hello Everyone - I hope I'm not posting this topic in the wrong place. I'm using iPerf to test a virtual network links. I have my network on Mininet, and I'm trying to set a fixed file size using -n but it seems like I have something wrong. The default packet size for TCP is 128 KB, when I run the code mininet>h2 iperf -c h1 -n 1 I can see the transmitted file size is 128 KB, but when I run mininet>h2 iperf -c h1 -n 2 I don't see any change. I was expecting to see 256 KB. Can you please tell me what is wrong?



Thank you very much!

kgersen

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Question about iPerf -n
« Réponse #1 le: 28 avril 2016 à 16:00:14 »
hi there.

"-n <value>" <value> is the total number of bytes to transmit not the number of buffers.
The online help (--help option) is accurate, the online doc is false.

use -n 256k to send 256KB

notice also that it will always send a number of 'full' buffers so if you ask for "-n 129k" and the buffer size is 128k, it will send 2x128k=256k and not 129k. That's why -n 1 and -n 2 do the same thing.

aa657

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Question about iPerf -n
« Réponse #2 le: 28 avril 2016 à 16:19:52 »
Thank you very much. I really appreciate your help  :D