On Tue, Jan 17, 2012 at 10:13:31AM +0000, Joe Thornber wrote: > iii) We add support to patch metadata changes into the running > metadata device. This would allow us to map the origin directly into > the pools data device (eg, using a linear target). And then introduce > a mapping for that origin. This would mean the origin would appear as > a thin dev within the pool. Have you considered just doing this part first? If there's a way that an existing linear region could be considered a data source for a pool, then wouldn't you get full support of existing LVM2 volumes (read-only and read/write) for free, at one fell swoop? Given that it's relatively rare that volume groups get moved, this could even be something which is done as a off-line conversion step so that existing LVM volumes are treated as "thin-provisioned voumes" that happened to be fully provisioned, with some flag so that a discard operation doesn't cause the blocks to be freed for use by some other thin-provisioned volume, but instead is propagated down to the hardware (for better SSD performance). - Ted -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel
