PegoraroF10 <marcos(at)f10(dot)com(dot)br> writes:
> Values for autovacuum and autoanalyse are Null because I did not configured
> them for system tables yet, but I´m doing vacuum manually once a week. My
> question now is why those selects varies that way.
Well, one point is that the execution time would probably vary hugely
depending on what's supplied for the parameters in
WHERE n.nspname LIKE $4 AND t.relname LIKE $5
which you haven't told us. I'm also wondering about just how many rows
get emitted by "generate_series($2, indnatts - $3)", and why that
particular part of the query makes any sense at all.
regards, tom lane