Re: ported application having performance issues

On Thu, 30 Jun 2005, John Mendenhall wrote:

> Our setting for effective_cache_size is 2048.
>
> random_page_cost = 4, effective_cache_size = 2048   time approximately 4500ms
> random_page_cost = 3, effective_cache_size = 2048   time approximately 1050ms
> random_page_cost = 3, effective_cache_size = 4096   time approximately 1025ms
>
> The decrease of random_page_cost to 3 caused the plan
> to work properly, using the lead_requests table as a
> join starting point and using the contacts index.

The effective_cache_size still looks small. As a rule of tumb you might
want effective_cache_size to be something like 1/2 or 2/3 of your total
memory. I don't know how much you had, but effective_cache_size = 4096 is
only 32M.

shared_buffers and effective_cache_size is normally the two most important
settings in my experience.

--
/Dennis Björklund