XCP-ng
    • Categories
    • Recent
    • Tags
    • Popular
    • Users
    • Groups
    • Register
    • Login

    CPU Stats bottoming out to Zero every five minutes

    Scheduled Pinned Locked Moved Xen Orchestra
    10 Posts 5 Posters 209 Views 4 Watching
    Loading More Posts
    • Oldest to Newest
    • Newest to Oldest
    • Most Votes
    Reply
    • Reply as topic
    Log in to reply
    This topic has been deleted. Only users with topic management privileges can see it.
    • D Offline
      DKirk
      last edited by

      I am running four instances of xcp-ng 8.3 with latest maintenance patches installed over the weekend. All four servers are the same Dell R720 but two of the boxes have a little more load than the other two. When viewing the stats of the two heavier loaded boxes they are now showing a CPU usage dropping to zero every 5 minutes or thereabouts. The server logs are totally empty and there is no slowness felt during these "outages". Is anybody else seeing this, or know what is going on, it appears to be a display problem only so far.

      Running XO Community:

      • Xen Orchestra, commit 9a833
      • Master, commit a82af

      2025-06-03 08_12_29-xcp-ng-us-3 (ADS-US-3) - Brave.png

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

        Hi,

        First time I'm seeing this. To remove XO from the equation, I would check the RRD values. Pinging @andriy.sultanov to assist in here

        A 1 Reply Last reply Reply Quote 0
        • D Offline
          DKirk
          last edited by

          It doesn't seem to be entirely 5 minute based, looking at the second server I see a different interval. When I get a minute I'll pull some raw RRD data for you.

          2025-06-03 14_35_08-xcp-ng-us-1 (ADS-US-1) - Brave.png

          1 Reply Last reply Reply Quote 0
          • D Offline
            DKirk
            last edited by

            It would seem that I am seeing this effect on all four of my servers, the usage was too low to see the event before. Here is my 3rd busiest server:

            2025-06-03 14_38_25-xcp-ng-us-4 (ADS-US-4) - Brave.png

            tjkreidlT 1 Reply Last reply Reply Quote 0
            • tjkreidlT Offline
              tjkreidl Ambassador @DKirk
              last edited by

              @DKirk Very odd. Maybe a electrical power issue? Do you see this if you run xentop on each host and really important, do they happen at the same time on all your servers?
              Any chance they are overheating and pausing briefly?

              D 1 Reply Last reply Reply Quote 0
              • D Offline
                DKirk @tjkreidl
                last edited by

                @tjkreidl No chance of electrical issue as all four servers have dual power supplies fed by two independent UPSs. This oddity only began after the updates applied three days ago. Does not happen with the same frequency or timing. A/C server room sitting at 70 degrees, all four servers racked together with great air flow. Again, this just started after the last updates.

                tjkreidlT 1 Reply Last reply Reply Quote 0
                • abudefA Offline
                  abudef
                  last edited by

                  I also see it in my lab

                  a8724945-0587-4dbb-b666-af5d8155e171-obrazek.png

                  2a478c3e-20db-428e-bdb7-987940ae25a0-obrazek.png

                  1 Reply Last reply Reply Quote 0
                  • A Offline
                    andriy.sultanov Vates 🪐 XAPI & Network Team @olivierlambert
                    last edited by

                    @olivierlambert I think this has already been fixed upstream (https://github.com/xapi-project/xen-api/pull/6458) - I will backport it for the release after the LTS and see if it fixes the issue for people in this thread.

                    BengangY opened this pull request in xapi-project/xen-api

                    closed CA-409482: Using computed delay for RRD loop #6458

                    D 1 Reply Last reply Reply Quote 1
                    • D Offline
                      DKirk @andriy.sultanov
                      last edited by

                      @andriy.sultanov - that sure sounds like it, thank you, let me know if I can help in any way. These are production servers but I can't imagine RRD causing any issues for them.

                      1 Reply Last reply Reply Quote 1
                      • tjkreidlT Offline
                        tjkreidl Ambassador @DKirk
                        last edited by

                        @DKirk That all makes sense, thanks for clarifying. Looks like there are further comments below that seem to pinpoint where the issue may lay. The key point you make is only "after the last updates" is when this started happening!

                        1 Reply Last reply Reply Quote 0
                        • First post
                          Last post