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    [solved] pfSense (2.6.0 & 22.01 ) is very slow on Hyper-V

    Scheduled Pinned Locked Moved Virtualization
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    • D
      Dominixise @stephenw10
      last edited by

      @stephenw10

      Hi Steve I can setup a zoom session with you on my server unless that requires paid tech support from netgate?

      Dom

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      • stephenw10S
        stephenw10 Netgate Administrator
        last edited by

        I'm not the guy for that, I know next to nothing about hyper-v. 😉

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        • D
          Dominixise @stephenw10
          last edited by

          packetcapture.zip @stephenw10

          Could be a Microsoft error too, I remember just after Christmas there was an windows update that cause some Hyper-V errors and maybe some are still present. My Server is up to date.

          But heres a packet capture of a speed testpacketcapture.zip

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          • D
            Dominixise @Dominixise
            last edited by

            @dominixise
            Also pftop while doing a speed testdom pfsense pftop.jpg

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            • stephenw10S
              stephenw10 Netgate Administrator
              last edited by

              No actual speedtesting shown there, was it filtered?

              All small packets, some MTU issue?

              Steve

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              • D
                Dominixise @stephenw10
                last edited by

                @stephenw10
                Sorry i am new to getting logs, try this onepacketcapture (1).zip

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                • stephenw10S
                  stephenw10 Netgate Administrator
                  last edited by

                  Nearly! 😉

                  You probably want to filter by the client IP you are running the test on, if you're capturing on LAN. And set the capture to, say, 5000 packets.

                  Steve

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                  • D
                    Dominixise @stephenw10
                    last edited by

                    @stephenw10

                    Okay thanks for the acknowledgment here is the new capture, I had to put the download on my webserver for download since its 5MB

                    https://zebrita.publicvm.com/files/packetcapture(2).cap

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                    • D
                      Dominixise @Dominixise
                      last edited by

                      @dominixise
                      Here is another one with just my host ip

                      https://zebrita.publicvm.com/files/packetcapture(3).cap

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                      • R
                        RMH 0
                        last edited by

                        A bit of digging and it looks like 2 issues to me.

                        One in Hyper-V which I have now got resolved, fix below (well for me anyhow)
                        One in pfsense that is missreporting throughput (I can live with that till a fix comes)

                        For Hyper-V I found this article on RSC https://www.doitfixit.com/blog/2020/01/15/slow-network-speed-with-hyper-v-virtual-machines-on-windows-server-server-2019/
                        Once I disabled RSC on all virtual switches my speed was back to normal. No restart needed, just go on to Hyper-V host, open powershell and input commands to disable RSC on each virtual switch.

                        These are commands I used

                        Get-VMSwitch -Name LAN | Select-Object RSC
                        Checks status, if true run next command LAN is my vswitch name

                        Set-VMSwitch -Name LAN -EnableSoftwareRsc $false
                        This disables RSC, re run first command to confirm it is disabled

                        If your vSwitch has a space in the name add "" around the name
                        Get-VMSwitch -Name "WAN #1" | Select-Object RSC

                        After applying speed is back to normal but pfsense seems to top out showing throughput at 60mb, even though I was getting over 500mb.

                        Anyhow, hope it helps thers on Hyper-V (this is a 2019 instance of Hyper-V)

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                        • D
                          DonZalmrol @RMH 0
                          last edited by DonZalmrol

                          @rmh-0 fantastic find!

                          I can confirm this has resolved it for me to, I'll leave it as is until a fix comes out.

                          Speed with RSC enabled:
                          aa9d7a1f-03e1-4815-8854-27b95d33d70f-image.png

                          Speed with RSC disabled:
                          063932be-5af6-48e6-9189-946fb1ed99c3-image.png

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                          • Bob.DigB
                            Bob.Dig LAYER 8
                            last edited by

                            Disabling RSC did nothing good for me at least. Problem with super slow SMB-Share over VLAN persists.

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                            • stephenw10S
                              stephenw10 Netgate Administrator
                              last edited by

                              Mmm, RSC is TCP only so I guess that explains why you saw much better throughput with a UDP VPN.
                              But I'm unsure how the pfSense update would trigger that...

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                              • D
                                DonZalmrol @stephenw10
                                last edited by

                                @stephenw10 maybe with the new FreeBSD kernel release it activated some incompatible functions for Windows Server on a network card level? e.g. thanks to @RMH-0 I disabled RSC and it returned to a normal level.

                                I know that about 7 years ago I needed to turn off VMQ in a large environment due to a bug in it that caused the guest VMs to all work incredibly slow...

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                                • R
                                  RMH 0 @DonZalmrol
                                  last edited by

                                  @donzalmrol If you do not mind a quick query as yours is OK now. Do you get a similar representation of throughput in pfsense in comparison to the spee test.

                                  I get the below which is way different. Trying to see if I have another issue or if others have the same.

                                  Speed.png

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                                  • P
                                    PaulPrior
                                    last edited by

                                    Disabling RSC did nothing for my environment. Inter-vLAN rate are still a fraction of what they were. Between machines on the same vLAN a file copy takes 3 seconds, between vLANs via the pfSense this jumps to 45-90 minutes.
                                    ce0bdc46-a06f-4d01-a6de-5b1294b917ae-image.png

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                                    • P
                                      PaulPrior @PaulPrior
                                      last edited by

                                      @paulprior This is a file copy in action between vLANs. There are 10Gb\s virtual adapters!
                                      3f1128cd-6128-4a0a-9cc8-77b7f99a6946-image.png

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                                      • P
                                        PaulPrior @PaulPrior
                                        last edited by

                                        @paulprior From Windows:
                                        6a704438-ca12-4b3a-b5fd-0708f6efb385-image.png

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                                        • Bob.DigB
                                          Bob.Dig LAYER 8
                                          last edited by

                                          Maybe they are different problems, I for myself had no problem with my WAN speed from the beginning.

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                                          • P
                                            PaulPrior
                                            last edited by

                                            So, disabling RSC has restored the network speed between VMs behind the pfSense and the internet (HTTPS download speeds), but the inter-vlan SMB file copy speeds are awful. Not quite dial-up modem speeds but almost.

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