Re: Script to compute random page cost - Mailing list pgsql-hackers

From Curt Sampson
Subject Re: Script to compute random page cost
Date
Msg-id Pine.NEB.4.44.0209101520240.13186-100000@angelic.cynic.net
Whole thread Raw
In response to Re: Script to compute random page cost  (Bruce Momjian <pgman@candle.pha.pa.us>)
List pgsql-hackers
On Tue, 10 Sep 2002, Bruce Momjian wrote:

> 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.

Actually, the random versus sequential time may also be different
depending on how many processes are competing for disk access, as
well. If the OS isn't maintaining readahead for whatever reason,
sequential access could, in theory, degrade to being the same speed
as random access. It might be interesting to test this, too.

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
 



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