I couldn't reproduce this with a vm whose xml includes:
<memory>524288</memory> <currentMemory>524288</currentMemory> <vcpu>1</vcpu> <os> <type arch='x86_64' machine='pc-1.2'>hvm</type> <boot dev='hd'/> </os> <features> <acpi/> <apic/> <pae/> </features> <clock offset='utc'/> <on_poweroff>destroy</on_poweroff> <on_reboot>restart</on_reboot> <on_crash>restart</on_crash> <devices> <emulator>/usr/bin/kvm</emulator> <disk type='file' device='disk'> <driver name='qemu' type='raw'/> <source file='/home/serge/machines/clean-precise-mini-amd64/disk0.img'/> <target dev='vda' bus='virtio'/> <address type='pci' domain='0x0000' bus='0x00' slot='0x04' function='0x0'/> </disk>
I started the vm, ran 6 kernel compilations, did 'virsh save/virsh restore', then did 6 more kernel compilations. All were in 272 or 273 seconds.
I couldn't reproduce this with a vm whose xml includes:
<memory> 524288< /memory> y>524288< /currentMemory> 'pc-1.2' >hvm</type> destroy< /on_poweroff> restart< /on_reboot> restart< /on_crash> /usr/bin/ kvm</emulator> home/serge/ machines/ clean-precise- mini-amd64/ disk0.img' />
<currentMemor
<vcpu>1</vcpu>
<os>
<type arch='x86_64' machine=
<boot dev='hd'/>
</os>
<features>
<acpi/>
<apic/>
<pae/>
</features>
<clock offset='utc'/>
<on_poweroff>
<on_reboot>
<on_crash>
<devices>
<emulator>
<disk type='file' device='disk'>
<driver name='qemu' type='raw'/>
<source file='/
<target dev='vda' bus='virtio'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x04' function='0x0'/>
</disk>
I started the vm, ran 6 kernel compilations, did 'virsh save/virsh restore', then did 6 more kernel compilations. All were in 272 or 273 seconds.