Il 11/06/2012 09:59, Kevin Wolf ha scritto: >>>>> >>>> I agree, doing it like mirroring for new writes on the top layer >>>>> >>>> makes >>>>> >>>> sense, as long as you are willing to violate the (optional) speed >>>>> >>>> parameter. I wouldn't think violating the speed parameter in that >>>>> >>>> case >>>>> >>>> would be an issue, as long as it is a documented affect of >>>>> >>>> performing a >>>>> >>>> live commit on the active (top) layer. >>> >> The question is what the speed parameter really means for a live commit >>> >> block job (or for an active mirror). I think it would make sense to >>> >> limit only the speed of I/O that doesn't come from the guest but is from >>> >> the background copying. >> > >> > Not necessarily, you can throttle the copying speed. If the I/O from >> > the guest has bursts, you will pick up the work later when the rate >> > calms down. > Then it's not an active mirror any more, but a passive one.
Yes, I guess what I was saying is that the passive mirror code can be used also for live commit of the top image. Paolo
