On Fri, Dec 21, 2012 at 11:13 PM, Alasdair G Kergon <agk@xxxxxxxxxx> wrote: > On Fri, Dec 21, 2012 at 10:54:21PM +0000, Greg Stark wrote: >> took about 30 minutes. I don't know why or what happened there. But it > > Big snapshots take a long time to load - the whole cow area has to be > scanned to generate the list of blocks represented on it. Hm. I didn't remember this happening previously but I had just doubled the size of the cow and I might be wrong about it too. I have another question while I'm here and people are being so helpful. Is there a way to grow the size of the actual snapshot device? Not the cow table but the device that the snapshot is presenting? If I change the size of the underlying device I don't think it changes the size of the snapshot and if I extend the snapshot it just changes the size of the cow table. It seems like it should be possible to add another dm mapping for the added space using a simple linear mapping. [btw Alasdair, Hi! We met at FOSDEM and discussed filesystem/dm synchronization primitives that would help Postgres have more lightweight checkpoints] -- greg -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel
