what is it about pg_dumpall that necessitates an immediate VACUUM to
restore performance?
in upgrading recently from a pre-7.1 release to a 7.1.3 release for a
fairly sizeable database, i noticed a severe decrease in performance
that seemed to be related only to the new version of postgres that was
running. everything else, including DBI, DBD::Pg, etc., remained the same.
i had done a pg_dumpall to preserve the data.
after a VACUUM, performance returned to within acceptable limits.
does pg_dumpall and the subsequent restoration of data create a bunch of
proverbial dust that needs to be vacuumed?
-tfo