KVM | qemu | qemu-system-x86_64 | High CPU load with Windows 10 guest.

Your Windows 10 guests use much more CPU percents than older Windows 7 guests – even when doing really nothing? (process is qemu-system-x86_64) Do virsh edit GUEST Change <clock offset=’localtime’> <timer name=’rtc’ tickpolicy=’catchup’/> <timer name=’pit’ tickpolicy=’delay’/> <timer name=’hpet’ present=’no’/> <timer name=’hypervclock’ present=’yes’/> </clock> To <clock offset=’localtime’> <timer name=’hpet’ present=’yes’/> <timer name=’hypervclock’ present=’yes’/> </clock> Kudos to […]

kvm | linux | shrink sparse disk using zerofree

Install zerofree edit your fstab, set your root drive to RO like /dev/vda1 / ext2 ro 0 1 Halt your system # halt -p Start your system into the grub menu, then select rescue mode, then drop to root shell Run zerofree like # zerofree /dev/vda1 Remount your root drive RW # mount -o remount,rw […]

kvm | qemu | qcow2 dynamic/sparse disk allocation problem | shrink sparse qcow2 disks howto

In some recent qemu versions there is a problem while creating sparse disks using the virt-manager. Normally the qcow2 format always allocates space dynamically (sparse), but some qemu versions fail at this, they create disks with full expected size. Solution: Create your disks manually: Shrinking existing images: # mv disk.qcow2 disk.qcow2.orig # qemu-img convert -O […]

KVM | host network interface settings on debian

First do: https://bytesandbones.wordpress.com/2018/02/22/debian-disabling-the-spooky-network-manager/   Then edit /etc/network/interfaces like:   # This file describes the network interfaces available on your system # and how to activate them. For more information, see interfaces(5). source /etc/network/interfaces.d/* # The loopback network interface auto lo iface lo inet loopback iface enp1s0f0 inet manual auto br0 iface br0 inet static address […]