Willy-Bas Loos <willybas@gmail.com> writes:
> [ pg_dump sometimes fails with ]
> pg_dump: [archiver (db)] query failed: ERROR: cache lookup failed for
> index 231808363
This wouldn't be too surprising if you're constantly creating and dropping
indexes. There's a small window between where pg_dump starts its
transaction and where it's able to acquire lock on each table; but since
it's working from a transaction-start-time view of the catalogs, it would
still expect the table to have all the indexes it did at the start.
If you've got a lot of DDL going on, maybe the window wouldn't even be
that small: pg_dump's attempt to lock some previous table might've blocked
for awhile due to DDL on that one.
regards, tom lane