Re: Bitmap scan cost model (was Re: bitmap scans, btree scans, and tid order) - Mailing list pgsql-hackers

From Zeugswetter Andreas DAZ SD
Subject Re: Bitmap scan cost model (was Re: bitmap scans, btree scans, and tid order)
Date
Msg-id E1539E0ED7043848906A8FF995BDA5790C5170@m0143.s-mxs.net
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List pgsql-hackers
> But to get the estimated cost ratio to match up with the actual cost
> ratio, we'd have to raise random_page_cost to nearly 70, which is a bit
> hard to credit.  What was the platform being tested here?

Why ? Numbers for modern single disks are 1-2Mb/s 8k random and 50-120 Mb/s
sequential.

Andreas


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