If we examine some performance parameters in postgresql, I will mention a few parameters that will be quite useful for performance.
You can configure the following parameters in the postgresql.conf file.
shared_buffer –> This parameter is the cache parameter. When setting the size of Shared Buffer it is recommended to set it to 25% larger than memory and 50% smaller than memory. In case of large set, it may cause other problems.
work_mem –> The amount of memory to be given for each connection.
maintenance_work_mem –> The memory used when performing vacuum indexing.
effective_cache_size –> 3/4 of the total ram can be given.
wall_buffer –>writeahed log cache. The value can be up to 16MB. This value can be reduced if desired.
checkpoint_segments –> The default value is 10. A check point is made in 10 segments. Can be increased if desired.
You can read the second articl of performance series. “POSTGRESQL DATABASE PERFORMANCE – 2”