On Tue, 12 Jan 2016, Mykola Golub wrote: > On Mon, Jan 11, 2016 at 09:00:18PM -0500, Boris Lukashev wrote: > > In case anyone is following the mailing list later on, we spoke in IRC > > and Sage provided a patch - http://fpaste.org/309609/52550203/ > > > diff --git a/src/osd/PG.cc b/src/osd/PG.cc > > index dc18aec..f9ee23c 100644 > > --- a/src/osd/PG.cc > > +++ b/src/osd/PG.cc > > @@ -135,8 +135,16 @@ void PGPool::update(OSDMapRef map) > > name = map->get_pool_name(id); > > if (pi->get_snap_epoch() == map->get_epoch()) { > > pi->build_removed_snaps(newly_removed_snaps); > > - newly_removed_snaps.subtract(cached_removed_snaps); > > - cached_removed_snaps.union_of(newly_removed_snaps); > > + interval_set<snapid_t> intersection; > > + intersection.intersection_of(newly_removed_snaps, cached_removed_snaps); > > + if (!(intersection == cached_removed_snaps)) { > > + newly_removed_snaps.subtract(cached_removed_snaps); > > Sage, won't it still violate the assert? > "intersection != cached_removed_snaps" means that cached_removed_snaps > contains snapshots missed in newly_removed_snaps, and we can't subtract? Oops, yeah, just remote the !. As you can see the problem is that the OSDMap's removed snaps shrank somehow. If you crank up logging you can see what the competing sets are. An alternative fix/hack would be to modify the monitor to allow the snapids that were previously in the set to be added back into the OSDMap. That's arguably a better fix, although it's a bit more work. But, even then, something like the above will be needed since there are still OSDMaps in the history where the set is smaller. sage > > > + cached_removed_snaps.union_of(newly_removed_snaps); > > + } else { > > + lgeneric_subdout(g_ceph_context, osd, 0) << __func__ << " cached_removed_snaps shrank from " << cached_removed_snaps << dendl; > > + cached_removed_snaps = newly_removed_snaps; > > + newly_removed_snaps.clear(); > > + } > > snapc = pi->get_snap_context(); > > } else { > > newly_removed_snaps.clear(); > > -- > Mykola Golub > > > -- To unsubscribe from this list: send the line "unsubscribe ceph-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
