QEMU KVM Libvirt手册(10): KVM的各种限制

Overcommits

KVM allows for both memory and disk space overcommit.
However, hard errors resulting from exceeding available resources will result in guest failures.
CPU overcommit is also supported but carries performance implications.

Time Synchronization

kvm-clock
NTP or similar network based time keeping protocols are also highly recommended (for VM Host Server and VM Guest) to help maintain a stable time.
Running NTP inside the guest is not recommended when using the kvm-clock .

MAC addresses

If no MAC address is specified for a NIC, a default MAC address will be assigned.
This may result in network problems when more than one NIC receives the same MAC address.
It is recommended to always assure a unique MAC address has been assigned for each NIC.

Live Migration

Live Migration is only possible between VM Host Servers with the same CPU features and no physical devices passed from host to guest.
Guest storage has to be accessible from both VM Host Servers and guest definitions need to be compatible.
VM Host Server and VM Guests need to have proper timekeeping installed.

User Permissions

The management tools (Virtual Machine Manager, virsh, vm-install) need to authenticate with libvirt

Suspending/Hibernating the VM Host Server

Suspending or hibernating the VM Host Server system while guests are running is not supported.

Performance

QEMU KVM Libvirt手册(10): KVM的各种限制

时间： 2024-10-30 22:11:30

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