OK, I have a better version at:

        ftp://candle.pha.pa.us/pub/postgresql/randcost

I have added a null loop which does a dd on a single file without
reading any data, and by netting that loop out of the total computation
and increasing the number of tests, I have gotten the following results
for three runs:
        
        random test:       36
        sequential test:   33
        null timing test:  27
        
        random_page_cost = 1.500000

        
        random test:       38
        sequential test:   32
        null timing test:  27
        
        random_page_cost = 2.200000
        

        random test:       40
        sequential test:   31
        null timing test:  27
        
        random_page_cost = 3.250000

Interesting that random time is increasing, while the others were
stable.  I think this may have to do with other system activity at the
time of the test.  I will run it some more tomorrow but clearly we are
seeing reasonable numbers now.

-- 
  Bruce Momjian                        |  http://candle.pha.pa.us
  [EMAIL PROTECTED]               |  (610) 359-1001
  +  If your life is a hard drive,     |  13 Roberts Road
  +  Christ can be your backup.        |  Newtown Square, Pennsylvania 19073

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