[SOLVED] Enabling memory hotplugging results in incorrect RAM allocation?

Discussion in 'Proxmox VE: Installation and configuration' started by MrBMT, May 18, 2018.

  1. MrBMT

    MrBMT New Member
    Proxmox VE Subscriber

    Dec 19, 2017
    Likes Received:

    I have a personal Proxmox environment I use for testing, for it I use the community repo which is running the latest version of proxmox VE (5.2-2). Full package version list:

    proxmox-ve: 5.2-2 (running kernel: 4.15.17-1-pve)
    pve-manager: 5.2-1 (running version: 5.2-1/0fcd7879)
    pve-kernel-4.15: 5.2-1
    pve-kernel-4.15.17-1-pve: 4.15.17-9
    corosync: 2.4.2-pve5
    criu: 2.11.1-1~bpo90
    glusterfs-client: 3.8.8-1
    ksm-control-daemon: 1.2-2
    libjs-extjs: 6.0.1-2
    libpve-access-control: 5.0-8
    libpve-apiclient-perl: 2.0-4
    libpve-common-perl: 5.0-31
    libpve-guest-common-perl: 2.0-16
    libpve-http-server-perl: 2.0-8
    libpve-storage-perl: 5.0-23
    libqb0: 1.0.1-1
    lvm2: 2.02.168-pve6
    lxc-pve: 3.0.0-3
    lxcfs: 3.0.0-1
    novnc-pve: 0.6-4
    proxmox-widget-toolkit: 1.0-18
    pve-cluster: 5.0-27
    pve-container: 2.0-23
    pve-docs: 5.2-4
    pve-firewall: 3.0-8
    pve-firmware: 2.0-4
    pve-ha-manager: 2.0-5
    pve-i18n: 1.0-5
    pve-libspice-server1: 0.12.8-3
    pve-qemu-kvm: 2.11.1-5
    pve-xtermjs: 1.0-5
    qemu-server: 5.0-26
    smartmontools: 6.5+svn4324-1
    spiceterm: 3.0-5
    vncterm: 1.5-3
    The server I am testing with has:
    Intel Xeon E3-1246 v3 @ 3.50GHz (8 Cores, 1 Socket)
    32GB RAM
    2x 2TB HDD (in RAID1, so 2TB usuable space)

    With memory hotplugging enabled the VPS boots with 931M RAM, and that never changes despite trying leaving it as the pre-defined value for the VM (2 GB) and changing the allocated memory to the VM via the web-interface (to 8GB).

    The web interface says that it has however much RAM assigned that you set it to under hardware (2GB, 8GB, etc.) however the actual VM never updates to reflect this.

    At first I wondered if this was something to do with ballooning, so created a C program to exceed the 931M RAM assigned, but all it did was exceed that then start using the swap space instead.

    The hypervisor has ~28GB RAM free, so it's not due to lack of memory either.

    The qemu configuration and terminal access showing this is as per below:

    root@de-hyp ~ # qm terminal 101
    starting serial terminal on interface serial0 (press Ctrl+O to exit)
    Debian GNU/Linux 9 v6-certauth ttyS0
    v6-certauth login: root
    Last login: Fri May 18 15:31:59 BST 2018 on ttyS0
    Linux v6-certauth 4.9.0-6-amd64 #1 SMP Debian 4.9.88-1+deb9u1 (2018-05-07) x86_64
    The programs included with the Debian GNU/Linux system are free software;
    the exact distribution terms for each program are described in the
    individual files in /usr/share/doc/*/copyright.
    Debian GNU/Linux comes with ABSOLUTELY NO WARRANTY, to the extent
    permitted by applicable law.
    root@v6-certauth ~ free -h
                  total        used        free      shared  buff/cache   available
    Mem:           931M         58M        809M        2.8M         63M        770M
    Swap:          2.0G          0B        2.0G
    cat /etc/pve/qemu-server/102.conf
    agent: 1
    bootdisk: virtio0
    cores: 8
    hotplug: disk,network,usb,memory
    ide2: none,media=cdrom
    memory: 2048
    name: v6-stats
    net0: virtio=A2:7C:D8:08:44:AC,bridge=vmbr0,firewall=1
    numa: 1
    onboot: 1
    ostype: l26
    scsihw: virtio-scsi-pci
    serial0: socket
    smbios1: uuid=c9a034ef-61cd-4063-b1bc-3d461a33c720
    sockets: 1
    virtio0: local-lvm:vm-102-disk-1,size=25G
    root@de-hyp ~ #
    Any ideas why this wouldn't be working? As soon as I switch off memory hotplugging and reboot the VM it starts up with the correct amount of RAM assigned.

  2. spirit

    spirit Well-Known Member
    Proxmox VE Subscriber

    Apr 2, 2010
    Likes Received:
    Stop hovering to collapse... Click to collapse... Hover to expand... Click to expand...
    chrone and MrBMT like this.
  3. MrBMT

    MrBMT New Member
    Proxmox VE Subscriber

    Dec 19, 2017
    Likes Received:
    Thank you! That was it. It's now working as it should do. the local PVE 'Help' docs mentioned about adding a the line for the vCPU hotplug, but nothing about the memory one.
  1. This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
    By continuing to use this site, you are consenting to our use of cookies.
    Dismiss Notice