Re: [Qemu-devel] Live Migration with different block devices

[Paolo Bonzini]

Il 25/06/2014 16:32, Xiongzi Ge ha scritto:
> I should make it clearer. I want to use a device for caching for the
> guest in host A. Then after the guest migrating to Host B, there is also
> a device for caching in Host B.   I want to the guest can access the new
> cache device in Host B at first automatically. I also want the guest can
> access the previous cache device in Host A, if it gets a miss. Here, I
> may need to modify some interfaces. Is there a simple way to do this?

If your caching is done in the guest, the guest must use O_DIRECT to 
open the block device.

Paolo