On Friday 09 July 2004 13:51, Alasdair G Kergon wrote: > On Fri, Jul 09, 2004 at 11:52:00AM -0500, Kevin Corry wrote: > > On Thursday 08 July 2004 9:34 pm, Daniel Phillips wrote: > > > - What is the advantage of passing the sector address instead > > > a direct index into the target table? > > I believe it's easier in general for applications to work with the > offset than it would be to work with the index (which will often > be completely arbitrary). The offset can be trusted to remain > constant across a range of operations that change the index. > [e.g. pvmove, remapping bad blocks etc.] Let's work though this nice and slowly please. You're saying that LVM2 can go change the table, e.g., by inserting a mirror for pvmove, at any time. But if that happens, we can end sending the message to the wrong target (e.g., a temporary mirror instead of the snapshot target) regardless of whether it's indexed by logical sector or ordinary index. Is that correct? Regards, Daniel