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OpenVPN performance of the RT-AC86U

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You'd get less than that.. Remember that beside the crypto, the router still has to handle things like routing. Right now, I devised things so the first OpenVPN server uses the second CPU core, while the routing is done on the first core. If you also run a server on the first core, it will have to compete with routing on CPU time.

Merlin, I have an AC56U that I bought previously, largely to run your firmware to use it as an openvpn client. My wifi was being handled by an older N16 router. I just bought the AC86U and, given it’s specs, would like it to handle both tasks now (vpn client and wifi). Do you think the vpn performance I get would be impacted much if it is also handling wireless duties? Family of 3 so probably max of 5 wireless devices going at the same time (if that matters).

Also, I was pretty lucky with overclocking the AC56U to 1.4 from 800. Have you played with overclocking the AC86U at all?
 
Merlin, I have an AC56U that I bought previously, largely to run your firmware to use it as an openvpn client. My wifi was being handled by an older N16 router. I just bought the AC86U and, given it’s specs, would like it to handle both tasks now (vpn client and wifi). Do you think the vpn performance I get would be impacted much if it is also handling wireless duties? Family of 3 so probably max of 5 wireless devices going at the same time (if that matters).

Impossible to say, it depends on your Internet connection. The wifi itself is handled by dedicated CPUs within each radio chips, however your main CPU still has to handle routing, AiProtection's DPI engine, etc...
 
Impossible to say, it depends on your Internet connection. The wifi itself is handled by dedicated CPUs within each radio chips, however your main CPU still has to handle routing, AiProtection's DPI engine, etc...
I have set it up now and everything is working great. My openvpn speeds (using PIA) are almost the same as regular (110 Mbps vs 120 Mbps). It's the same whether I'm using the Ethernet or the wifi.

I am having one very odd problem though. When I am using openvpn over the wifi connection, my upload speeds are atrocious. Wifi upload without openpvn is 10Mbps. Openvpn without wifi is 9Mpbs. Openvpn with wifi is less than 1Mpbs. Is that a bug, or easily explained?
 
I don't get that significant of a speed drop on uploads when running PIA on an AC1900P and using WiFi.

What does the CPU load look like?
 
The CPU load didn't look any different from when I was uploading over the vpn using the ethernet. It's really odd.

It almost looks like a RAM thing, as a few time's I've seen a second or two at the start where it's showing high speeds and then it just crashes down to nothing.
 
Okay, the issue with my upload speeds over wireless appears to be related to using UDP in the openvpn settings. If I switch to TCP my wireless upload speeds are great. Within 10% of my wired speeds and several times faster than UDP. But unfortunately my wireless download speeds get cut almost in half moving to TCP.

Again, UDP uploads just great over a wired connection, and also works great downloading over wireless. And in both wired and wireless, UDP download is twice as fast as TCP download.

Here are the results I'm getting (download/upload Mbps):

No VPN (both wired and wireless): 125/10.5
VPN with UDP - wired: 120/10.0
VPN with UDP - wireless: 120/1.5
VPN with TCP - wired: 75/9.5
VPN with TCP - wireless: 65/9.5

So since I want to keep my very fast UDP download speeds, is there a setting I can change to make UDP upload speeds work well over wireless? I assume from some reading that I am experiencing packet loss issues. Is this one of those times to use an sndbuf or rcvbuf setting?

What's really surprising (for me, anyway), is that I didn't think the wireless communication between the device and the router had really anything to do with the VPN...it's just sending information between the wireless devices and router over the usual wifi network. It's the router that's doing the whole VPN encryption/communication thing with the ISP. I'm confused why the wifi transmission between the device and the router would have any real impact on what's happening between the router and the ISP.

For what it's worth, there is no noticeable difference in CPU load, whether I am using wired or wireless, UDP or TCP. Upload actually seems to use hardly any CPU at all.
 
Okay, the issue with my upload speeds over wireless appears to be related to using UDP in the openvpn settings. If I switch to TCP my wireless upload speeds are great. Within 10% of my wired speeds and several times faster than UDP. But unfortunately my wireless download speeds get cut almost in half moving to TCP.

Again, UDP uploads just great over a wired connection, and also works great downloading over wireless. And in both wired and wireless, UDP download is twice as fast as TCP download.

Here are the results I'm getting (download/upload Mbps):

No VPN (both wired and wireless): 125/10.5
VPN with UDP - wired: 120/10.0
VPN with UDP - wireless: 120/1.5
VPN with TCP - wired: 75/9.5
VPN with TCP - wireless: 65/9.5

So since I want to keep my very fast UDP download speeds, is there a setting I can change to make UDP upload speeds work well over wireless? I assume from some reading that I am experiencing packet loss issues. Is this one of those times to use an sndbuf or rcvbuf setting?

What's really surprising (for me, anyway), is that I didn't think the wireless communication between the device and the router had really anything to do with the VPN...it's just sending information between the wireless devices and router over the usual wifi network. It's the router that's doing the whole VPN encryption/communication thing with the ISP. I'm confused why the wifi transmission between the device and the router would have any real impact on what's happening between the router and the ISP.

For what it's worth, there is no noticeable difference in CPU load, whether I am using wired or wireless, UDP or TCP. Upload actually seems to use hardly any CPU at all.

Thank you so much for your awesome test report!!! I hope that RMerlin will hunt this issue down.

I Will for sure order this router ASAP
 
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I decided today to wait for the upcoming Black Friday.....that's around the corner. But this router shall be mine!!!
Any more Client Speed tests?
 
Okay, the issue with my upload speeds over wireless appears to be related to using UDP in the openvpn settings. If I switch to TCP my wireless upload speeds are great. Within 10% of my wired speeds and several times faster than UDP. But unfortunately my wireless download speeds get cut almost in half moving to TCP.

Again, UDP uploads just great over a wired connection, and also works great downloading over wireless. And in both wired and wireless, UDP download is twice as fast as TCP download.

Here are the results I'm getting (download/upload Mbps):

No VPN (both wired and wireless): 125/10.5
VPN with UDP - wired: 120/10.0
VPN with UDP - wireless: 120/1.5
VPN with TCP - wired: 75/9.5
VPN with TCP - wireless: 65/9.5

So since I want to keep my very fast UDP download speeds, is there a setting I can change to make UDP upload speeds work well over wireless? I assume from some reading that I am experiencing packet loss issues. Is this one of those times to use an sndbuf or rcvbuf setting?

What's really surprising (for me, anyway), is that I didn't think the wireless communication between the device and the router had really anything to do with the VPN...it's just sending information between the wireless devices and router over the usual wifi network. It's the router that's doing the whole VPN encryption/communication thing with the ISP. I'm confused why the wifi transmission between the device and the router would have any real impact on what's happening between the router and the ISP.

For what it's worth, there is no noticeable difference in CPU load, whether I am using wired or wireless, UDP or TCP. Upload actually seems to use hardly any CPU at all.


Hi there!
Thank you for your test results. Any change since stable release? I'm thinking particulary of the upload Speed. Is it Still slow/slower?

Thanks
 
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Any speed progress after firmware's stable???

I have been using the RT-86 (Asuswrt-Merlin) for a month behind PIA. These are the results over the last few days with the VPN enabled. Connection from my ISP is 150 down 15 up - so obviously I'm pretty happy with these results.

i-Qttv26R-XL.jpg
 
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@kap55 which PIA VPN is used in your testing?

Not quite sure I understand what you are asking, but the PIA server I connect to is in Toronto if that is what you would like to know.

I was getting about 90 down using VPN Client 2 with Merlin. When I switched to Client 3 it went to about 125 down. For some reason I started getting 150+ down about 4 or 5 days ago.
 
Thank you for the info.

I was surprised and curious about the PIA OpenVPN's awesome throughput.
 
I was surprised as well - especially the last few days when it went above 125 down.

Just for your info I am not able to get any reasonable speed with NordVPN. 20 down was max after spending hours trying different servers/settings.
 

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