Gregory Stark <stark@enterprisedb.com> writes:
>> For "Server Drives" 3-4ms are more realistic ([2], [3]) for average seeks and
>> the 110-170MB/sec are highly exaggerated.
>
> In that case both of those numbers come straight from Seagate's data sheet for
> their top-of-the-line data centre drives:
>
> http://www.seagate.com/docs/pdf/datasheet/disc/ds_cheetah_15k_6.pdf
Oh, but I just noticed they separately quote latency and read/write seek time.
The average read seek time is 3.4ms. That gives a random_page_cost of 45-71.
-- Gregory Stark EnterpriseDB http://www.enterprisedb.com Ask me about EnterpriseDB's PostGIS support!