Oliver Elphick wrote: > Available memory (512M) exceeds the total database size, so sequential > and random are almost the same for the second and subsequent runs. > > Since, in production, I would hope to have all active tables permanently > in RAM, would there be a case for my using a page cost of 1 on the > assumption that no disk reads would be needed?
Yes, in your case random_page_cost would be 1 once the data gets into RAM. In fact, that is the reason I used only /data/base for testing so places where data can load into ram will see lower random pages costs. I could just create a random file and test on that but it isn't the same. -- Bruce Momjian | http://candle.pha.pa.us [EMAIL PROTECTED] | (610) 359-1001 + If your life is a hard drive, | 13 Roberts Road + Christ can be your backup. | Newtown Square, Pennsylvania 19073 ---------------------------(end of broadcast)--------------------------- TIP 5: Have you checked our extensive FAQ? http://www.postgresql.org/users-lounge/docs/faq.html
