I hate to respond by suggesting an alternative but it may be good to try using pg_basebackup (Doc: http://www.postgresql.org/docs/9.1/static/app-pgbasebackup.html) to back-up your database. It takes a copy of the file system files rather than querying the data as an ordinary connection which is much faster. Straight file system backup is fast too but it may be more difficult to restore the database to a consistent state. At this point pg_dump is very good for exporting specific tables or schemas or for loading data into another dbms but it is slow and has a lot of overhead because of MVCC. pg_basebackup is faster, but does require you take a backup of the entire cluster.
Sachin Srivastava wrote: > How can I fast my daily pg_dump backup. Can I use parallel option(Which is introduced in Postgres 9.3) > with Postgres 9.1. There is any way I can use this is for 9.1 database.
You cannot do that.
Switch to file system backup, that is much faster.