Proxmox 4 Pb to allocate memory to Windows VM

[Kan]

Hello,

I have 128GB on host and created 2 VM with Windows Server 2012 (nothing running on the 2 Windows, just fresh install). When I fill 4096/102400 to auto allocation for each VM, I can start the first VM but fail for the second because there's not enough free RAM on host.

Balloon drivers are correctly installed on each Windows.

root@prox11:/# free -m
total used free shared buffers cached
Mem: 128924 97644 31280 68 3 144
-/+ buffers/cache: 97495 31428
Swap: 8191 439 7752

The first VM really uses less than 5GB RAM (Task Manager).

What should I do to make host not to reserve RAM like this ?

kvm: cannot set up guest memory 'pc.ram': Cannot allocate memory
TASK ERROR: start failed: command '/usr/bin/kvm -id 101 -chardev 'socket,id=qmp,path=/var/run/qemu-server/101.qmp,server,nowait' -mon 'chardev=qmp,mode=control' -pidfile /var/run/qemu-server/101.pid -daemonize -smbios 'type=1,uuid=91f82c9d-f41e-4862-b2c7-3d2fb7b885be' -name testwin2 -smp '2,sockets=1,cores=2,maxcpus=2' -nodefaults -boot 'menu=on,strict=on,reboot-timeout=1000,splash=/usr/share/qemu-server/bootsplash.jpg' -vga std -vnc unix:/var/run/qemu-server/101.vnc,x509,password -no-hpet -cpu 'kvm64,hv_spinlocks=0x1fff,hv_vapic,hv_time,hv_reset,hv_vpindex,hv_runtime,hv_relaxed,+lahf_lm,+sep,+kvm_pv_unhalt,+kvm_pv_eoi,enforce' -m 102400 -k fr -device 'pci-bridge,id=pci.2,chassis_nr=2,bus=pci.0,addr=0x1f' -device 'pci-bridge,id=pci.1,chassis_nr=1,bus=pci.0,addr=0x1e' -device 'piix3-usb-uhci,id=uhci,bus=pci.0,addr=0x1.0x2' -device 'usb-tablet,id=tablet,bus=uhci.0,port=1' -device 'virtio-balloon-pci,id=balloon0,bus=pci.0,addr=0x3' -iscsi 'initiator-name=iqn.1993-08.org.debian:01:7596b3e7dda' -drive 'file=/mnt/Nas01/template/iso/virtio-win-0.1.126-2.iso,if=none,id=drive-ide1,media=cdrom,aio=threads' -device 'ide-cd,bus=ide.0,unit=1,drive=drive-ide1,id=ide1,bootindex=200' -drive 'file=/mnt/Nas01/template/iso/SW_DVD5_Win_Svr_Std_and_DataCtr_2012_64Bit_French_Core_MLF_X18-27604.ISO,if=none,id=drive-ide2,media=cdrom,aio=threads' -device 'ide-cd,bus=ide.1,unit=0,drive=drive-ide2,id=ide2,bootindex=201' -drive 'file=/rpool/data2/images/101/vm-101-disk-1.qcow2,if=none,id=drive-virtio0,format=qcow2,cache=none,aio=native,detect-zeroes=on' -device 'virtio-blk-pci,drive=drive-virtio0,id=virtio0,bus=pci.0,addr=0xa,bootindex=100' -netdev 'type=tap,id=net0,ifname=tap101i0,script=/var/lib/qemu-server/pve-bridge,downscript=/var/lib/qemu-server/pve-bridgedown,vhost=on' -device 'virtio-net-pci,mac=3A:87:8B:10:F9:33,netdev=net0,bus=pci.0,addr=0x12,id=net0,bootindex=300' -rtc 'driftfix=slew,base=localtime' -global 'kvm-pit.lost_tick_policy=discard'' failed: exit code 1

 

[Kan]

When I set Share = 0 in allocated memory range, the memory used on host is OK (no more than memory min) but memory used in Task Manager (on Windows server) abnormally grows to 95%.

Please help.

 

[wolfgang]

Hi,

This is a normal Windows behavior.
Windows takes always all Ram what is available.
This is the reason why ballooning do not work with Windows.

 

[Kan]

I'm surprised by your answer. I don't understand what's the point of filling min and max value for RAM allocation if the max is always taken on host...

Do you mean RAM min/max allocation does not work only with Windows VM but should work with other kind of VM ?

 

[wolfgang]

With Linux and BSD it works fine.
The problem are only Windows machines.

 

[Kan]

OK thank you for information.