Am 10.06.2010 14:53, schrieb Anthony Liguori: > On 06/10/2010 04:43 AM, Kevin Wolf wrote: >> >> Huh, why this? Seems I still haven't understood all of qcow2 then... I >> always thought that there's just a specific offset where VM state >> starts, but no explicit end. >> > > A live snapshot can last for a very long time. What happens if you need > to allocate a new block for disk I/O while saving a snapshot?
You allocate it, I guess? Note that VM state must be virtually contiguous, but not necessarily physically (virtually = on the virtual hard disk as seen by the guest; physically = in the image file). It's just not seen by the guest because it's saved at a high offset that is after the end of the real disk content, but otherwise it should behave the same as guest data. Kevin -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
