2^64 byte in peta byte = 18446.744073709551616 (peta⋅byte) Assuming that a snapshot requires storing any data at all, which it must, nobody has a Ceph cluster that could store that much snapshot metadata even for empty snapshots. On Fri, Aug 4, 2023 at 7:05 AM Eugen Block <eblock@xxxxxx> wrote: > > I'm no programmer but if I understand [1] correctly it's an unsigned > long long: > > > int ImageCtx::snap_set(uint64_t in_snap_id) { > > which means the max snap_id should be this: > > 2^64 = 18446744073709551616 > > Not sure if you can get your cluster to reach that limit, but I also > don't know what would happen if you actually would reach it. I also > might be misunderstanding so maybe someone with more knowledge can > confirm oder correct me. > > [1] https://github.com/ceph/ceph/blob/main/src/librbd/ImageCtx.cc#L328 > > Zitat von Tony Liu <tonyliu0592@xxxxxxxxxxx>: > > > Hi, > > > > There is a snap ID for each snapshot. How is this ID allocated, sequentially? > > Did some tests, it seems this ID is per pool, starting from 4 and > > always going up. > > Is that correct? > > What's the max of this ID? > > What's going to happen when ID reaches the max, going back to start > > from 4 again? > > > > > > Thanks! > > Tony > > _______________________________________________ > > ceph-users mailing list -- ceph-users@xxxxxxx > > To unsubscribe send an email to ceph-users-leave@xxxxxxx > > > _______________________________________________ > ceph-users mailing list -- ceph-users@xxxxxxx > To unsubscribe send an email to ceph-users-leave@xxxxxxx _______________________________________________ ceph-users mailing list -- ceph-users@xxxxxxx To unsubscribe send an email to ceph-users-leave@xxxxxxx