On 2010-05-30 20:34, Tom Lane wrote:
> Jesper Krogh<jesper(at)krogh(dot)cc> writes:
>> testdb=# set seq_page_cost = 0.00001;
>> testdb=# set random_page_cost = 0.00001;
> Well, hmm, I really doubt that that represents reality either. A page
> access is by no means "free" even when the page is already in cache.
> I don't recall anyone suggesting that you set these numbers to less
> than perhaps 0.01.
Thank you for the prompt response. Is it a "false assumption" that the
cost should in some metric between different plans be a measurement
of actual run-time in a dead-disk run?
It should most likely be matching a typical workload situation, but that
it really hard to tell anything about, so my "feeling" would be that the
dead disk case is the one closest?
In response to
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