On Fri, Nov 30, 2001 at 09:12:53AM -0600, Jason L Tibbitts III wrote: > >>>>> "JT" == Joe Thornber <thornber@btconnect.com> writes: > > JT> It's a nice idea, but with the current implementation there's no > JT> way I'd want 100 snapshots of the same origin hanging around. > > They wouldn't all be of the same LV, fortunately; I split my VG up > into lots of manageable chunks. (Large users get a volume to > themselves, small users get grouped into various user volumes.) But > still, I assume that you have some details of performance with the > current snapshot implementation. Is it that bad? Well, it does - copy on write (COW) synchronously *before* et allows the write to the original LV to proceed - do multiple reads in case you`ve got multiple snapshots - does the COWs for multiple snapshots sequentially This leads to an unecessary read per additional snapshot on the original LV and therefore to something around n-times delay in case you've got n snapshots. We will have an asynchrounous implementation which avoids multiple reads with LVM2. > > - J< > > _______________________________________________ > linux-lvm mailing list > linux-lvm@sistina.com > http://lists.sistina.com/mailman/listinfo/linux-lvm > read the LVM HOW-TO at http://www.sistina.com/lvm/Pages/howto.html -- Regards, Heinz -- The LVM Guy -- =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- Heinz Mauelshagen Sistina Software Inc. Senior Consultant/Developer Am Sonnenhang 11 56242 Marienrachdorf Germany Mauelshagen@Sistina.com +49 2626 141200 FAX 924446 =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
