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    CPU Usage when network used

    Scheduled Pinned Locked Moved Problems Installing or Upgrading pfSense Software
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    • stephenw10S
      stephenw10 Netgate Administrator
      last edited by

      So try changing:

      hw.ix.rxd: 2048
      hw.ix.txd: 2048
      hw.ix.flow_control: 3
      

      You might need to set the individual flowcontrol values:

      dev.ix.0.fc: 3
      

      I'd start out by doubling the descriptor values. Set the flowcontrol to 0 and check that in ifconfig.

      Steve

      1 Reply Last reply Reply Quote 0
      • T
        tman222
        last edited by tman222

        Thanks for the update. Beyond what @stephenw10 already suggested, you might also consider changing (increasing) the processing limits on the ix interfaces using the following tunables:

        dev.ix.Y.tx_processing_limit
        dev.ix.Y.rx_processing_limit

        where Y = 0.....N and N is the number of ix interfaces in your system minus 1. Setting the rx and tx processing limit to -1 essentially removes the limit (i.e. makes it unlimited).

        However, even with updated tunables, it appears challenging to make up almost 6.5 Gbit/s or throughput (though I could be wrong). I have a couple more questions:

        1. What are specs of the machines on either side that you are using for testing? If you put them both on the same subnet, are they able to talk at 10 Gbit/s to each other?

        2. Are you running any other add-on packages on pfSense currently or is this a barebones install?

        Hope this helps.

        1 Reply Last reply Reply Quote 1
        • Q
          qwaven
          last edited by

          I've tried setting the hw.ix.rxd values as well as the flow control but I'm not seeing the values change even after a reboot. In PFSense I created the values and put 4096.

          sysctl hw.ix.rxd
          hw.ix.rxd: 2048

          Same with this, its set to 0.

          sysctl hw.ix.flow_control
          hw.ix.flow_control: 3

          Am I doing this wrong?

          The last one appears to already be 0.

          sysctl dev.ix.0.fc
          dev.ix.0.fc: 0

          Where should these be set? Are these also via sysctl?

          dev.ix.Y.tx_processing_limit
          dev.ix.Y.rx_processing_limit

          1. The destination is a NAS and the source is a linux distro on a Z800 workstation. Yes when I tried them on the same vlan they reached 10G instantly. They will also reach it network-to-network when PF is disabled.
          2. Not much running on PFSense right now. Barely any firewall rules, mostly only configured basic connectivity, dns, pppoe/nat, and 1 VPN, most of this is not used for the reaching each network (all internal)

          Thanks all for the help.
          Cheers!

          FYI:
          tunables.PNG

          1 Reply Last reply Reply Quote 0
          • Q
            qwaven
            last edited by

            Any thoughts on the above? Hoping to make sure I've at least done this correctly.

            Cheers!

            1 Reply Last reply Reply Quote 0
            • stephenw10S
              stephenw10 Netgate Administrator
              last edited by

              You probably need to add them as loader variables rather than system tunables as shown here:
              https://docs.netgate.com/pfsense/en/latest/hardware/tuning-and-troubleshooting-network-cards.html#adding-to-loader-conf-local

              Steve

              1 Reply Last reply Reply Quote 1
              • Q
                qwaven
                last edited by

                Thanks. I've put this. Does this look correct before I reboot?

                #Improve Cache size
                hw.ix.rxd: 4096
                hw.ix.txd: 4096
                #Change processing limit -1 is unlimited
                dev.ix.-1.tx_processing_limit
                dev.ix.-1.rx_processing_limit

                Cheers!

                GrimsonG 1 Reply Last reply Reply Quote 0
                • GrimsonG
                  Grimson Banned @qwaven
                  last edited by

                  @qwaven said in CPU Usage when network used:

                  Thanks. I've put this. Does this look correct before I reboot?

                  #Improve Cache size
                  hw.ix.rxd: 4096
                  hw.ix.txd: 4096

                  Nope, read the syntax in the documentation again.

                  #Change processing limit -1 is unlimited
                  dev.ix.-1.tx_processing_limit
                  dev.ix.-1.rx_processing_limit

                  Also nope, read it again:
                  @tman222 said in CPU Usage when network used:

                  dev.ix.Y.tx_processing_limit
                  dev.ix.Y.rx_processing_limit

                  where Y = 0.....N and N is the number of ix interfaces in your system minus 1. Setting the rx and tx processing limit to -1 essentially removes the limit (i.e. makes it unlimited).

                  1 Reply Last reply Reply Quote 1
                  • Q
                    qwaven
                    last edited by

                    Thanks. Not sure I've seen documentation just going on what was posted earlier. However I've changed to this?

                    hw.ix.rxd="4096"
                    hw.ix.txd="4096"

                    Also I found this, I am not clear what the difference between hw and dev is.
                    hw.ix.tx_process_limit="-1"
                    hw.ix.rx_process_limit="-1"

                    Cheers!

                    GrimsonG 1 Reply Last reply Reply Quote 0
                    • GrimsonG
                      Grimson Banned @qwaven
                      last edited by

                      @qwaven said in CPU Usage when network used:

                      Thanks. Not sure I've seen documentation just going on what was posted earlier. However I've changed to this?

                      hw.ix.rxd="4096"
                      hw.ix.txd="4096"

                      Also I found this, I am not clear what the difference between hw and dev is.
                      hw.ix.tx_process_limit="-1"
                      hw.ix.rx_process_limit="-1"

                      Cheers!

                      Looks better, hw. is global while dev. is per device.

                      1 Reply Last reply Reply Quote 1
                      • stephenw10S
                        stephenw10 Netgate Administrator
                        last edited by

                        Yeah looks good.
                        Not sure why but the flow control global setting doesn't seem to work for ixgbe. It needs to be set per dev using the dev.ix.X values. That may apply to the process limits, I've never tested it.

                        Steve

                        1 Reply Last reply Reply Quote 2
                        • Q
                          qwaven
                          last edited by

                          So thanks all for your efforts. I'm pretty much thinking I'm sol here. :)

                          Rebooted with those settings, confirmed I can see them applied. Tried some tests with iperf3
                          single stream, -P10, and 3 separate streams on different ports. Nothing has changed, still about 3G speed.

                          In regards to flow control it looked like it was already set to 0 before so I have not forced anything via loader...etc.

                          Cheers!

                          1 Reply Last reply Reply Quote 0
                          • stephenw10S
                            stephenw10 Netgate Administrator
                            last edited by

                            flowcontrol set to 0 in hw.ix or dev.ix.X?

                            If the link shows as media: Ethernet autoselect (10Gbase-Twinax <full-duplex,rxpause,txpause>) it's still enabled.

                            Steve

                            1 Reply Last reply Reply Quote 0
                            • Q
                              qwaven
                              last edited by

                              Interesting yes it appears to be.

                              ifconfig | grep media
                                      media: Ethernet autoselect (1000baseT <full-duplex>)
                                      media: Ethernet autoselect (10Gbase-T <full-duplex>)
                                      media: Ethernet autoselect
                                      media: Ethernet autoselect (10Gbase-Twinax <full-duplex,rxpause,txpause>)
                                      media: Ethernet autoselect (1000baseT <full-duplex>)
                                      media: Ethernet autoselect (1000baseT <full-duplex>)
                                      media: Ethernet autoselect (10Gbase-Twinax <full-duplex,rxpause,txpause>)
                                      media: Ethernet autoselect (10Gbase-T <full-duplex>)
                                      media: Ethernet autoselect (10Gbase-T <full-duplex>)
                                      media: Ethernet autoselect (10Gbase-T <full-duplex>)
                              

                              added this into the loader.conf.local but it appears to have had no effect.

                              dev.ix.0.fc=0
                              dev.ix.1.fc=0
                              dv.ix.2.fc=0
                              dev.ix.3.fc=0
                              

                              then tried

                              hw.ix.flow_control="0"
                              

                              which seems to have worked.

                              ifconfig | grep media
                                      media: Ethernet autoselect (1000baseT <full-duplex>)
                                      media: Ethernet autoselect (10Gbase-T <full-duplex>)
                                      media: Ethernet autoselect
                                      media: Ethernet autoselect (10Gbase-Twinax <full-duplex>)
                                      media: Ethernet autoselect (1000baseT <full-duplex>)
                                      media: Ethernet autoselect (1000baseT <full-duplex>)
                                      media: Ethernet autoselect (10Gbase-Twinax <full-duplex>)
                                      media: Ethernet autoselect (10Gbase-T <full-duplex>)
                                      media: Ethernet autoselect (10Gbase-T <full-duplex>)
                                      media: Ethernet autoselect (10Gbase-T <full-duplex>)
                              

                              however after running similar iperf3 tests as before the best I've seen is about this:

                              [  5]  30.00-30.04  sec  15.6 MBytes  3.11 Gbits/sec
                              

                              Cheers!

                              1 Reply Last reply Reply Quote 0
                              • stephenw10S
                                stephenw10 Netgate Administrator
                                last edited by

                                Interesting. The opposite if what I have previously seen. Hmm.

                                Disappointing it did help. Might have reach the end of the road. At least for low hanging fruit type tweaks.

                                Steve

                                1 Reply Last reply Reply Quote 0
                                • Q
                                  qwaven
                                  last edited by

                                  Yeah appreciate all the help from everyone. Learned a thing or two anyhow. :)
                                  I'll likely blow this install out when I have a bit more time and virtualize it with some other stuff. Go the L3 switch route which seems like that should work.

                                  Cheers!

                                  1 Reply Last reply Reply Quote 0
                                  • JeGrJ
                                    JeGr LAYER 8 Moderator
                                    last edited by JeGr

                                    @qwaven were those latest tests you made with MTU 1500 or MTU 9000? Perhaps try again with MTU9000 set on all parts of that network segment? The results strike me some similarity as:

                                    https://calomel.org/network_performance.html

                                    As for other optimizations: you could check the loader.conf and sysctl.conf values setup on
                                    https://calomel.org/freebsd_network_tuning.html
                                    and adjust yours carefully in that direction.

                                    Don't forget to upvote 👍 those who kindly offered their time and brainpower to help you!

                                    If you're interested, I'm available to discuss details of German-speaking paid support (for companies) if needed.

                                    1 Reply Last reply Reply Quote 1
                                    • Q
                                      qwaven
                                      last edited by qwaven

                                      Thanks for the info. I have applied some of this "freebsd network tuning" and I seem to have managed to make it slower. :P

                                      May play around with it a little more, will let you know if it amounts to anything.

                                      Cheers!

                                      1 Reply Last reply Reply Quote 0
                                      • T
                                        tman222
                                        last edited by

                                        Something here still seems off to me that you're hitting this 3Gbit/s limit and can't get further. I know the Atom CPU you're using is slower than the Xeon D I have my box, but I don't expect it to be that much slower.

                                        A couple more questions that come to mind right now:

                                        1. Have you tried different set of SFP+ modules and/or fiber cables? If using a direct attached copper connection instead, have you tried a different cable?
                                        2. Try this for me: Open two SSH sessions to your pfSense box. On one session launch the iperf3 server, i.e. "iperf3 -s". On the other session run an iperf3 test to localhost, i.e. "iperf3 -c localhost". What do the results look like? Hopefully they're nice and high.
                                        3. Have you looked in the system's BIOS to make sure everything is configured properly? For instance, do you have any power saving setting enabled? Might want to disable them for testing (i.e. go max performance).

                                        Hope this helps.

                                        1 Reply Last reply Reply Quote 0
                                        • Q
                                          qwaven
                                          last edited by

                                          @tman222 said in CPU Usage when network used:

                                          Something here still seems off to me that you're hitting this 3Gbit/s limit and can't get further. I know the Atom CPU you're using is slower than the Xeon D I have my box, but I don't expect it to be that much slower.

                                          That's where I'm still confused. I have 16x2Ghz core's. Most of them are not used when I do anything which means to me that the system is not working very hard unless there is some bottleneck elsewhere I have not seen.

                                          I'm using DAC cables. I have tried replacing them from from used ones to brand new ones. I did not see anything change in doing so. :P

                                          Won't be able to do the test until later but I'll try and let you know.

                                          Re bios I did check things out but I did not see anything obvious to change. I'll check again anyway.

                                          Cheers!

                                          GrimsonG 1 Reply Last reply Reply Quote 0
                                          • GrimsonG
                                            Grimson Banned @qwaven
                                            last edited by

                                            @qwaven said in CPU Usage when network used:

                                            That's where I'm still confused. I have 16x2Ghz core's. Most of them are not used when I do anything which means to me that the system is not working very hard unless there is some bottleneck elsewhere I have not seen.

                                            You should really read the contents of the sites you are pointed at, from https://calomel.org/network_performance.html

                                            No matter what operating system you choose, the machine you run on will determine the theoretical speed limit you can expect to achieve. When people talk about how fast a system is they always mention CPU clock speed. We would expect an AMD64 2.4GHz to run faster than a Pentium3 1.0 GHz, but CPU speed is not the key, motherboard bus speed is.

                                            I/O operations don't count as CPU usage, but these are the main limiting factor in packet based operations like networking and especially when it comes to routing.

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