Re: One large v. many small - Mailing list pgsql-performance

From Andrew Sullivan
Subject Re: One large v. many small
Date
Msg-id 20030130130240.I983@mail.libertyrms.com
Whole thread Raw
In response to One large v. many small  (Noah Silverman <noah@allresearch.com>)
Responses Re: One large v. many small
List pgsql-performance
On Thu, Jan 30, 2003 at 12:34:36PM -0500, Noah Silverman wrote:
> Select (*) from client_4 where foo=2;
>
> A query from the new, proposed system would be
>
> Select (*) from big_results where client=4 and foo=2.
>
> The big questions is, WHICH WILL BE FASTER with Postgres.  Is there any
> performance improvement or cost to switching to this new structure.

Faster overall, or faster for that operation?  I can't prove it, but
I suspect that the first one will return faster just because both the
index and the table itself is smaller.

The possibility is thatit will cause you problems overall, however,
because of the large number of files you have to keep if you use 3000
tables.  This is dependent on your filesytem (and its
implementation).

Note, too, that a lot of transactions frequently updating the table
might make a difference.  A large number of dead tuples sitting on a
10 million row table will make anything crawl.

A

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