petchimuthu lingam <[EMAIL PROTECTED]> schrieb:

> Hi friends,
> 
> I am using postgresql 8.1, I have shared_buffers = 50000, now i execute the
> query, it takes 18 seconds to do sequential scan, when i reduced to 5000, it
> takes one 10 seconds, Why.

Wild guess: the second time the data are in the filesystem cache.

> 
> Can anyone explain what is the reason, ( any other configuration is needed in
> postgresql.conf)

Show us the EXPLAIN ANALYSE - Output.


Andreas
-- 
Really, I'm not out to destroy Microsoft. That will just be a completely
unintentional side effect.                              (Linus Torvalds)
"If I was god, I would recompile penguin with --enable-fly."    (unknow)
Kaufbach, Saxony, Germany, Europe.              N 51.05082°, E 13.56889°

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