The question is now: how can the situation be improved? One way to do that is to run a CLUSTER clause:
test=# \h CLUSTERCommand: CLUSTERDescription: cluster a table according to an indexSyntax:CLUSTER [VERBOSE] table_name[ USING index_name ] CLUSTER [VERBOSE]
The CLUSTER clause will rewrite the table in the same order as a (b-tree) index. If you are running an analytical workload, this can make sense. However, in an OLTP system, the CLUSTER clause might not be feasible because a table lock is required while the table is rewritten.
