On Thu, Feb 14, 2013 at 08:28:03PM +0100, Igor Mammedov wrote:
On Thu, 14 Feb 2013 13:13:18 +0100
Paolo Bonzini <address@hidden> wrote:
Il 14/02/2013 12:18, Eduardo Habkost ha scritto:
qemu boots from disk image 3 times faster than direct kernel load.
That's surprising. Do you have any idea why that happens?
Because kernel load uses MMIO (from fw_cfg), while booting from disk
uses at worst PCI DMA and at best virtio.
Paolo
I've tried Paolo's suggestion to run in TCG mode with instruction logging,
and it spends too much time reading 11K kernel from qemu compared to
kvm-unit-test kernel. I'll need debug it further to find out why.
But this patch looks unnecessary if I could fix qemu/seabios or test kernel
to reach the same load time as kvm-unit-test kernel.
Agreed.
Lucas, please don't apply this patch yet, until we find the actual cause
of the slow booting.