[PERFORM] Can anyone explain this: duplicate dbs.

[SpaceBallOne]

Wondering if someone could explain a pecularity for me: We have a database which takes 1000ms to perform a certain query on. If I pg_dump that database then create a new database (e.g. "tempdb") and upload the dump file (thus making a duplicate) then the same query only takes 190ms !! Vacuum, vacuum analyse, and vacuum full analyse does not seem to have an impact on these times. Can anyone explain why this may be occurring and how I might be able to keep the original database running at the same speed as "tempdb"? Thanks in advance, Dave.