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

    VM's going really slow after 3 - 4 weeks

    Scheduled Pinned Locked Moved Solved Compute
    36 Posts 9 Posters 5.1k Views 7 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.
    • B Offline
      Berrick @Gheppy
      last edited by

      @Gheppy What is free disk space like on this VM?

      This is what caused the CPU's in our graylog server to go nuts. It had almost run out of free disk space. The only thing I have done was to increase free disk space by clearing out some of the older logs.

      72b922e6-3c6a-457e-984a-271e5ff95961-image.png

      B 1 Reply Last reply Reply Quote 0
      • GheppyG Offline
        Gheppy
        last edited by Gheppy

        There is free space, on real disks I have:

        • 4 x 400Gb SSD = 800Gb RAID 10, on which I have XCP-ng and the rest of the disk is with the first disk of the VM where is the operating system, which has 350 Gb allocated in which I have 2 partitions with 150 Gb SO and 200 Gb SQL log (for some speed). The occupied space being for SO 65Gb and for SQL log of 120Gb.

        • 14 x 1200Gb = 8.4Tb RAID 10, on which I have the rest of the database divided on 3 virtual disks of 2Tb with soft RAID in the OS ( which is windows ),the configuration is like this because of the XCP-ng limit of 2Tb per vdisk. The database currently has 3.7 Tb.

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

          @Gheppy If you run top, how is the dom0 CPU load and how is the swap space? If dom0 is saturated it may need more memory allocated to it.

          GheppyG 1 Reply Last reply Reply Quote 0
          • GheppyG Offline
            Gheppy
            last edited by Gheppy

            This is a top img, swap it seems to be ok but memory is 103 Mb free of 7.4Gb.
            I will increase the memory for Xen. Thank you
            a4628398-2b29-4965-ae22-76500a7c151c-image.png

            1 Reply Last reply Reply Quote 0
            • GheppyG Offline
              Gheppy @tjkreidl
              last edited by

              @tjkreidl
              I increased the RAM for Xen to 10Gb and it is much better, maximum 156% on CPU on xentop.
              Thank you

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

                @Gheppy You have to give dom0 enough CPU power for various reaasons: 1) to be able to not be bogged down, itself, 2) to allow VMs to be able to interact with dom0 reasonably fast, 3) to provide enough resources to deal with storage and network I/O. Showing essentially no swap space in use is good!

                1 Reply Last reply Reply Quote 0
                • B Offline
                  Berrick @Berrick
                  last edited by

                  Seasons greetings to all,

                  So the slowness of is creeping back. Still cant find any thing obvious
                  Latest Xen Top

                  4ccf84eb-8d2e-4434-bafc-cd38c43007f2-image.png

                  Due to business pressures we have had to reboot the physical server.
                  So now have to wait for the issue to re occur.

                  there were 5 more patch's which have been applied.

                  If anyone has any other suggestion of what to check, specific logs to search etc, etc they would be gratefully received

                  Kind regards

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

                    Adding @fohdeesha in the loop

                    1 Reply Last reply Reply Quote 0
                    • Tristis OrisT Offline
                      Tristis Oris Top contributor
                      last edited by

                      can't say that time from reboot a cause of problem, but sometimes i'm feel something about it. Even ssh connection takes tooooo long, like 10 sec in local network. Same for http speed for small services without any load.

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

                        @Berrick Run iostat and see if anything shows up as slow or saturated with your storage I/O.

                        1 Reply Last reply Reply Quote 1
                        • EddieCh08666741E Offline
                          EddieCh08666741
                          last edited by

                          hi Berrick, most of the issues that happen like this is due to IO i believe. I've been using XCP ng for many years and I have about 100 VMs. I love xcp and its the best out there. There are few instance that my VM starts to crawl to be unusable.

                          1. One of the disk fails in the raid and cause my VMs on that particular server to crawl.
                          2. Too little memory provisioned. Heavy usage.

                          Hope my above helps

                          tjkreidlT 1 Reply Last reply Reply Quote 0
                          • tjkreidlT Offline
                            tjkreidl Ambassador @EddieCh08666741
                            last edited by

                            @EddieCh08666741 Indeed. Run top and make sure you have adequate resources allocated for dom0 for both memory and CPU. There should be no swapping to speak of and the CPU should be nowhere close to 100% in use.

                            B 1 Reply Last reply Reply Quote 0
                            • B Offline
                              Berrick @tjkreidl
                              last edited by

                              Thanks for all the replies.
                              I will be checking when the issue starts again in a few weeks and report back.

                              From previous xentop output I don't believe Dom0 is showing high CPU or Memory.

                              I also dont think there is a problem with the physical disks.

                              B 1 Reply Last reply Reply Quote 0
                              • B Offline
                                Berrick @Berrick
                                last edited by

                                @Berrick
                                So its been a while since my last post on this topic but finally I think we have bottomed this issue out! 🙂

                                So the long and the short.
                                Nothing we tried, checked or diagnostics ran up to this point showed any issue.
                                Then one Monday morning there was one alert from the iLO about "Corrected Memory Error threshold exceeded"

                                As this server was due a memory upgrade to LV memory soon and we would need to reboot to clear the alert we brought the upgrade forward.

                                Since the new memory was installed, tempting fate here, it has been OK

                                Thanks to all that offered advice.

                                Kind regards

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

                                  Oh wow. So something was wrong with the hardware, specifically the memory, and potentially more errors and error correction trying to keep up, slowing down everything. Is it a good recap?

                                  B 1 Reply Last reply Reply Quote 0
                                  • B Offline
                                    Berrick @olivierlambert
                                    last edited by

                                    @olivierlambert said in VM's going really slow after 3 - 4 weeks:

                                    Oh wow. So something was wrong with the hardware, specifically the memory, and potentially more errors and error correction trying to keep up, slowing down everything. Is it a good recap?

                                    To be honest I am not entirely sure.
                                    I tested the memory my self in the early stages of this issue with memtest. In the past memtest has flagged memory issue that HP built in diags hasn't but it ran clean. 😞

                                    The server was rebooted prior to replacing the memory out of curiosity and everything came up OK no errors.

                                    So we assume that something was wrong with the memory. And now we have are fingers crossed that that is the end if it 🙂

                                    1 Reply Last reply Reply Quote 1
                                    • B Berrick marked this topic as a question on
                                    • B Berrick has marked this topic as solved on
                                    • First post
                                      Last post