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    Short VM freeze when migrating to another host

    Scheduled Pinned Locked Moved Compute
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    • robytR Offline
      robyt @nikade
      last edited by

      @nikade 2568c5bf-5336-4461-8f1f-60cf093f93a2-immagine.png
      in VM (linux) with a free i see 94 gb of total memory

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      • andrewperryA Offline
        andrewperry @nikade
        last edited by

        @nikade thanks for the ideas of where to look!

        In my case we're testing and just have a 1Gb link between these hosts, which is what I was putting it down to.

        This particular VM is a freshly migrated PV from Debian Xen with:

        Memory limits (min/max)
        Static: 16 MiB/16 GiB
        Dynamic: 8 GiB/16 GiB

        Could that Dynamic setting be the problem because as I recall it reduces the VM to 8 on migrate, so when doing the migrate perhaps 8 isn't enough for the VM?

        I will try changing it to 16/16 and see if that has any noticeable impact. Thanks!

        nikadeN 1 Reply Last reply Reply Quote 0
        • olivierlambertO Offline
          olivierlambert Vates 🪐 Co-Founder CEO
          last edited by

          Yes that's very likely.

          robytR 1 Reply Last reply Reply Quote 0
          • nikadeN Offline
            nikade Top contributor @andrewperry
            last edited by

            @andrewperry yeah try set it 16/16Gb instead, it will probably do some magic 🙂

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            • robytR Offline
              robyt @olivierlambert
              last edited by

              @olivierlambert hi, today i've upgraded my host..
              The big VM frozen for ~7 minutes, is a big vm (96 gbram and 32 cpu) but 7 minutes is a very long time (for customer!)
              i've setting 96/06 in dynamic: is a normal time?

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              • olivierlambertO Offline
                olivierlambert Vates 🪐 Co-Founder CEO
                last edited by

                Can you provide more details? 96/96 in dynamic? Just doing live migration or suspending the VM?

                robytR 1 Reply Last reply Reply Quote 0
                • robytR Offline
                  robyt @olivierlambert
                  last edited by

                  @olivierlambert live migration, the vm is very important (today, in christmas holyday, i've received some phone calls for 7 minutes of freeze..)
                  17407a92-730e-4e68-885f-44a4141e863d-immagine.png

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                  • olivierlambertO Offline
                    olivierlambert Vates 🪐 Co-Founder CEO
                    last edited by olivierlambert

                    The topology looks insane 🤔 Also, a live migration shouldn't make the VM inaccessible for more than few seconds, except if there is a LOT of memory pages changes, at a pace that is close to the transfer speed.

                    robytR 1 Reply Last reply Reply Quote 0
                    • robytR Offline
                      robyt @olivierlambert
                      last edited by

                      @olivierlambert ops.. why the best topology?

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                      • olivierlambertO Offline
                        olivierlambert Vates 🪐 Co-Founder CEO
                        last edited by

                        IIRC, just remove it (small cross) so it should use something default

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