Re: Do we need vacuuming when tables are regularly dropped?

Tom Lane wrote:
> "Scott Marlowe" <scott.marlowe@gmail.com> writes:
>
>> Also, there was a time when you couldn't do vacuum full on system
>> tables do to locking issues, and had to take the db down to single
>> user mode to do so.
>>
>
> There was a short period when *concurrent* vacuum fulls on just the
> wrong combinations of system catalogs could deadlock (because they both
> needed to look up stuff in the other one).  AFAIK we fixed that.  It's
> never been the case that it didn't work at all.
>
>             regards, tom lane
>
Never personally had trouble with vacuum full or reindex on system
tables. CLUSTER, however, is another story. While I've never run across
anything explicitly documenting that clustering system tables is
forbidden, I've also never used a version of PostgreSQL that allows it
(though I've never tried in single-user mode):

postgres@[local]=> CLUSTER pg_class USING pg_class_oid_index ;
ERROR:  "pg_class" is a system catalog

Should the docs
(http://www.postgresql.org/docs/8.3/interactive/sql-cluster.html) be
updated to note this restriction?

Cheers,
Steve