Cannot allocate more than 32Gb memory to a Windows VM


New Member
Oct 7, 2019

I am wondering why I currently cannot allocate more than 32Gb of memory to my windows VM.

System Specs
Linux pve 4.15.18-12-pve #1 SMP PVE 4.15.18-35 (Wed, 13 Mar 2019 08:24:42 +0100) x86_64

processor       : 0
vendor_id       : GenuineIntel
cpu family      : 6
model           : 62
model name      : Intel(R) Xeon(R) CPU E5-2680 v2 @ 2.80GHz
stepping        : 4
microcode       : 0x42d
cpu MHz         : 3127.271
cache size      : 25600 KB
physical id     : 0
siblings        : 20
core id         : 0
cpu cores       : 10
apicid          : 0
initial apicid  : 0
fpu             : yes
fpu_exception   : yes
cpuid level     : 13
wp              : yes
flags           : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx pdpe1gb rdtscp lm constant_tsc arch_perfmon pebs bts rep_good nopl xtopology nonstop_$bugs            : cpu_meltdown spectre_v1 spectre_v2 spec_store_bypass l1tf
bogomips        : 5600.11
clflush size    : 64
cache_alignment : 64
address sizes   : 46 bits physical, 48 bits virtual
power management:

MemTotal:       65996016 kB
MemFree:        31640808 kB
MemAvailable:   34689676 kB
Buffers:          751388 kB
Cached:          2558456 kB
SwapCached:       144008 kB
Active:         27190460 kB
Inactive:        4615628 kB
Active(anon):   25447212 kB
Inactive(anon):  3206196 kB
Active(file):    1743248 kB
Inactive(file):  1409432 kB
Unevictable:       19880 kB
Mlocked:           19880 kB
SwapTotal:       2097148 kB
SwapFree:          14428 kB

VM Config

See attached config file.

TASK ERROR: start failed: command '/usr/bin/kvm -id 100 -name Win10 -chardev 'socket,id=qmp,path=/var/run/qemu-server/100.qmp,server,nowait' -mon 'chardev=qmp,mode=control' -chardev 'socket,id=qmp-event,path=/var/run/qmeventd.sock,reconnect=5' -mon 'chardev=qmp-event,mode=control' -pidfile /var/run/qemu-server/ -daemonize -smbios 'type=1,uuid=42e5cab8-36e9-48c6-b520-a69684d6e7ff' -drive 'if=pflash,unit=0,format=raw,readonly,file=/usr/share/pve-edk2-firmware//OVMF_CODE.fd' -drive 'if=pflash,unit=1,format=raw,id=drive-efidisk0,file=/dev/pve/vm-100-disk-1' -smp '38,sockets=2,cores=19,maxcpus=38' -nodefaults -boot 'menu=on,strict=on,reboot-timeout=1000,splash=/usr/share/qemu-server/bootsplash.jpg' -vga none -nographic -no-hpet -cpu 'host,+kvm_pv_unhalt,+kvm_pv_eoi,hv_vendor_id=proxmox,hv_spinlocks=0x1fff,hv_vapic,hv_time,hv_reset,hv_vpindex,hv_runtime,hv_relaxed,hv_synic,hv_stimer,kvm=off' -m 35000 -object 'memory-backend-ram,id=ram-node0,size=17500M' -numa 'node,nodeid=0,cpus=0-18,memdev=ram-node0' -object 'memory-backend-ram,id=ram-node1,size=17500M' -numa 'node,nodeid=1,cpus=19-37,memdev=ram-node1' -device 'vmgenid,guid=bb51e300-ef5b-49c9-a3ec-b2834f18f706' -readconfig /usr/share/qemu-server/pve-q35.cfg -device 'usb-tablet,id=tablet,bus=ehci.0,port=1' -device 'vfio-pci,host=81:00.0,id=hostpci1,bus=ich9-pcie-port-2,addr=0x0' -device 'vfio-pci,host=83:00.0,id=hostpci2.0,bus=ich9-pcie-port-3,addr=0x0.0,multifunction=on' -device 'vfio-pci,host=83:00.1,id=hostpci2.1,bus=ich9-pcie-port-3,addr=0x0.1' -device 'virtio-balloon-pci,id=balloon0,bus=pci.0,addr=0x3' -iscsi '' -drive 'file=/dev/pve/vm-100-disk-0,if=none,id=drive-virtio0,format=raw,cache=none,aio=native,detect-zeroes=on' -device 'virtio-blk-pci,drive=drive-virtio0,id=virtio0,bus=pci.0,addr=0xa,bootindex=100' -device 'ahci,id=ahci0,multifunction=on,bus=pci.0,addr=0x7' -drive 'file=/dev/disk/by-uuid/5E568D63568D3D31,if=none,id=drive-sata1,format=raw,cache=none,aio=native,detect-zeroes=on' -device 'ide-hd,bus=ahci0.1,drive=drive-sata1,id=sata1' -netdev 'type=tap,id=net0,ifname=tap100i0,script=/var/lib/qemu-server/pve-bridge,downscript=/var/lib/qemu-server/pve-bridgedown,vhost=on' -device 'virtio-net-pci,mac=5A:6C:D5:54:5C:D9,netdev=net0,bus=pci.0,addr=0x12,id=net0,bootindex=300' -rtc 'driftfix=slew,base=localtime' -machine 'type=q35' -global 'kvm-pit.lost_tick_policy=discard'' failed: exit code 1


  • 100.conf.txt
    609 bytes · Views: 0

you get this in the error message one line before of the output you have sent
kvm: cannot set up guest memory 'pc.ram': Cannot allocate memory


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