Re: Script to compute random page cost

On Mon, 9 Sep 2002, Bruce Momjian wrote:

> What do other people get for this value?

With your new script, with a 1.5 GHz Athlon, 512 MB RAM, and a nice fast
IBM 7200 RPM IDE disk, I get random_page_cost = 0.933333.

> One flaw in this test is that it randomly reads blocks from different
> files rather than randomly reading from the same file.  Do people have a
> suggestion on how to correct this?  Does it matter?

From my quick glance, it also does a lot of work work to read each
block, including forking off serveral other programs. This would tend to
push up the cost of a random read. You might want to look at modifying
the randread program (http://randread.sourceforge.net) to do what you
want....

cjs
-- 
Curt Sampson  <cjs@cynic.net>   +81 90 7737 2974   http://www.netbsd.org   Don't you know, in this new Dark Age, we're
alllight.  --XTC