Re: Query on Postgresql performance - Mailing list pgsql-performance

From Neil Conway
Subject Re: Query on Postgresql performance
Date
Msg-id 1062640870.14624.13.camel@tokyo
Whole thread Raw
In response to Query on Postgresql performance  ("Naveen Palavalli" <palavall@ISI.EDU>)
List pgsql-performance
On Wed, 2003-09-03 at 15:32, Naveen Palavalli wrote:
> shared_buffers = 200

If you're using a relatively modern machine, this is probably on the low
side.

> 1) Effects related to Vaccum :- I performed 10 trials of adding and
> deleting entries . In each trial , 1 client  adds 10,000 entries and
> then deletes them . During the course of these 10 trials ,  the Add
> Rates (rate at which my server can add entries to the Postgresql
> database ) drops from  around 200 Adds/second in the 1st trial  to
> around 100 Adds/second in the 10th trial . But when I do a Vaccuum ,
> Immediately I get back the Add Rates to  around 200 Adds/Second .

Well, there's nothing wrong with vacuuming frequently (since it won't
block concurrent database operations, and the more often you vacuum, the
less time each vacuum takes).

> I was using Postgresql 7.3.3 earlier but it kept crashing the database
> after a Vaccum . So I switched to a older and stabler version  7.2.4

Can you reproduce the 7.3.3 crash? (BTW, in the future, it would be
appreciated if you could report these kinds of bugs to the dev team).

-Neil



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