On Thu, 11 Aug 2016, Igor Fedotov wrote: > Looks like BlueStore::collection_list method makes my day today :) > > While playing with new objectstore fio plugin (see > https://github.com/ceph/ceph/pull/10267) I observed BlueStore fsck reports > errors on restart. And completion if properly configured. > > After significant test case simplification it appeared that BlueStore::fsck > detects duplicate nid at the storage. More analysis showed that in fact it's > Bluestore::collection_list who returned duplicate entities. > > I have some gaps in my collection/object naming scheme understanding hence I > can't say definitely if fio assigns collection names properly. IMHO it's > rather an issue in BlueStore::collection_list. > > Here is pretty simple (hopefully) log (2 collections and 2 objects total) each > showing the case. > > IMHO the issue somewhere below the following line: > > 2016-08-11 18:30:44.595101 7fbe78f39780 1 bluestore(./fio-bluestore) fsck > collection 281474976710656.0_head > > where both object keys are reported. > > Sage, could you please take a look and comment. I think this is the problem: 2016-08-11 18:30:44.595104 7fbe78f39780 20 bluestore(./fio-bluestore) collection_list range '--'0x7ffefffffffffffe00000000'.' to '--'0x7ffefffffffffffeffffffff':' and '--'0x800100000000000000000000'.' to '--'0x8001000000000000ffffffff':' start GHMIN for the .0 collection it is scanning the hash range that includes the .1 collection. That's because create_collection is being passed a bit 'bits' value: 2016-08-11 18:30:43.697022 7fbe78f39780 15 bluestore(./fio-bluestore) _create_collection 281474976710656.0_head bits 0 2016-08-11 18:30:43.697037 7fbe78f39780 10 bluestore(./fio-bluestore) _create_collection 281474976710656.0_head bits 0 = 0 2016-08-11 18:30:43.697038 7fbe78f39780 15 bluestore(./fio-bluestore) _create_collection 281474976710656.1_head bits 0 2016-08-11 18:30:43.697042 7fbe78f39780 10 bluestore(./fio-bluestore) _create_collection 281474976710656.1_head bits 0 = 0 Since there are 2 collections, we need (at least) 1 significant bit. sage -- 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
