OpenVPN throughput is not as expected



  • I posted over on the OpenVPN board as well, but the basics are that I've set up PIA tunnels on pfsense and everything is working as I'd expect except throughput.  I wasn't expecting world beating performance, but I was expecting to see my CPU hit the wall in top and it's not.  So, 150Mbps down internet connection and I'm getting around 50Mbps of throughput.  What bugs me is that I never see an openvpn thread go above about 30% in top when doing a download test.

    Hardware:

    CPU: AMD Sempron 2650 (dual cores, 1.45Ghz, AES-NI support)
    Motherboard:  MSI AM1I
    RAM: 4GB DDR3
    NIC:  HP NC360T PCIe x4 (Intel® 82571EB, em driver)

    I'm not expecting world beating performance but can anyone explain why I top out at 50Mbps while openvpn is using 30% of a single core?  I'm still testing and switching back and forth between Blowfish and AES but I haven't seen much difference so far.  I've been contemplating a CPU upgrade but without openvpn demonstrably maxing out my CPU I'm wondering if it will be worth it.

    FWIW, I have tested with the PIA client on a linux box and have achieved close to my rated dl speed.



  • Have you confirmed the pfsense settings are the same as the PIA client?

    I usually stick everything in the advanced options instead of configuring it in the UI.

    Specifically I would check for MTU settings. I found that with my old provider it was better not to have them set.


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