Don't allow relminmxid to go backwards during VACUUM FULL

We were allowing a table's pg_class.relminmxid value to move backwards
when heaps were swapped by VACUUM FULL or CLUSTER.  There is a
similar protection against relfrozenxid going backwards, which we
neglected to clone when the multixact stuff was rejiggered by commit
0ac5ad5134f276.

Backpatch to 9.3, where relminmxid was introduced.

As reported by Heikki in
http://www.postgresql.org/message-id/52401AEA.9000608@vmware.com
This commit is contained in:
Alvaro Herrera 2014-06-27 14:43:46 -04:00
parent 4c888a6290
commit 9eecc8a7ca

View File

@ -861,6 +861,12 @@ copy_heap_data(Oid OIDNewHeap, Oid OIDOldHeap, Oid OIDOldIndex, bool verbose,
if (TransactionIdPrecedes(FreezeXid, OldHeap->rd_rel->relfrozenxid))
FreezeXid = OldHeap->rd_rel->relfrozenxid;
/*
* MultiXactCutoff, similarly, shouldn't go backwards either.
*/
if (MultiXactIdPrecedes(MultiXactCutoff, OldHeap->rd_rel->relminmxid))
MultiXactCutoff = OldHeap->rd_rel->relminmxid;
/* return selected values to caller */
*pFreezeXid = FreezeXid;
*pCutoffMulti = MultiXactCutoff;