On 02/16/2014 09:26 PM, Robert Haas wrote:
> I don't really know about cpu_tuple_cost. Kevin's often advocated
> raising it, but I haven't heard anyone else advocate for that. I
> think we need data points from more people to know whether or not
> that's a good idea in general.
In 10 years of tuning PostgreSQL professionally, I still don't have a
mathematical model for the interaction of the various *_cost parameters
with the speeds of CPU, RAM and IO. If someone else has one, please
post it so that we can make some intelligent decisions on defaults.
--
Josh Berkus
PostgreSQL Experts Inc.
http://pgexperts.com
