Tuning postgresql for better performance - ADempiere ERP

PostgreSQL is a highly customizable relational database management system (RDBMS) with a dazzling array of configuration options. The postgresql.conf file is located in the \PostgreSQL\9.x\Data folder. You can tune the following sections of the postgresql.conf file to get the best performance.
 
 
CONNECTIONS AND AUTHENTICATION
In this section change the following entries to the following:
max_connections = 350
authentication_timeout = 7min

RESOURCE USAGE (except WAL)
In this section change the following entries to the following:
shared_buffers = 256MB : PG Backends that need to access tables first look for needed blocks in this cache. If they are already there, they can continue processing right away. The change can be made with a postmaster command-line flag or by changing the value of shared_buffers
temp_buffers = 32MB
max_prepared_transactions = 20
work_mem = 1024MB
maintenance_work_mem = 1024MB

QUERY TUNING
effective_cache_size = 2048MB

RUNTIME STATISTICS
track_counts = on

AUTOVACUUM PARAMETERS
autovacuum = on

You can also configure the logging details. A detailed description is available hereAfter you make the changes, save the file and restart the server to implement the changes.

Find the best configuration for your resources. 
The following links may be helpful for better tuning