Alvaro Herrera wrote:
It's an arbitrary number, based on which all the other numbers are measured.
Now that I read more intensively he docs I see that all the cost parameters are related one with the other.
What people generally do around here is mess with random_page_cost, and leave seq_page_cost alone. Often, it's the ratio seq_page_cost/random_page_cost what's most important to the cost equations results. (seq_page_cost wasn't tunable at all until recently, say 8.1 or 8.2 AFAIR).
Ok, now the 8.1 server has a RAID1 hardware board with SCSI disks, and the 8.2 is just a PentiumD with SATA disks (it's my desktop PC where I do tests). Should I have a lower random_page_cost on a machine that is likely to have a lower disk IO speed?
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