Re: Backend memory leakage when inserting

Gerhard Hintermayer wrote:
> Should have investigated this better before posting:
>
> I have the following test case:
> PostgreSQL 7.3.1 on i686-pc-linux-gnu, compiled by GCC 2.95.2 (running
> a 2.2.23 kernel)
> create an empty database
> create table testdb(i integer,t timestamp);
>
> edit a file fill.sql with 500 identical lines:
> INSERT INTO testdb VALUES(1,'now()');
>
> check memory of backend process (ps axuw): Column RSS 3224
> \i fill.sql
> backend RSS 3295 (ok, some sort of basic mem probably)
> \i fill.sql ~ 10 times
> backend RSS 3300
> \i fill.sql ~ 25 times
> backend RSS 3304
> \i fill.sql ~ 70 times
> backend RSS 3316
>
> VSZ value is always the same (6248). So what's going on here ?
>
>
> (now i have ~ 53500 tuples in my table)
>
>
> I have no idea, what's going on here ? Any ideas ?
>
> Gerhard

Did compile postgreSQL (7.3.1) on a SuSE 8.1 box (Linux,2.4.19 kernel)
and see exactly the same behavior. Seems like the amount of leakage
depends on the size (number of tables, number of triggers ???) of the
whole database, on a empty database the memory growth rate is quite slow
(see posted example) , on the production system the mem usage was ~ 120
MB after ~ 300000 inserts.

Gerhard