Re: Memory and performance - Mailing list pgsql-sql

From Tom Lane
Subject Re: Memory and performance
Date
Msg-id 14398.986435610@sss.pgh.pa.us
Whole thread Raw
In response to Memory and performance  (edipoelder@ig.com.br)
Responses Re: Memory and performance
List pgsql-sql
edipoelder@ig.com.br writes:
>     I have noted that Postgresql don't make a good memory handle. I have 
> made the tables/procedure (in attached file) and run it as "select bench(10, 
> 5000)". This will give a 50000 records inserts (5 x 10000). (well, I run it 
> on a P200+64MB of RAM, under Linux, and Postgres 7.0.2. In a more powerfull 
> machine, you can try other values). 

>     I get as result, the following times: 

>  id | objname | benchtime 
> ----+---------+----------- 
>   1 | group 1 | 00:00:32 
>   2 | group 2 | 00:00:47 
>   3 | group 3 | 00:01:13 
>   4 | group 4 | 00:01:41 
>   5 | group 5 | 00:02:08 
> (5 rows) 

This is an inefficiency in handling of foreign-key triggers.  It's fixed
for 7.1 --- in current sources I get
id | objname  | benchtime
----+----------+----------- 1 | group 1  | 00:00:03 2 | group 2  | 00:00:03 3 | group 3  | 00:00:03 4 | group 4  |
00:00:035 | group 5  | 00:00:03 6 | group 6  | 00:00:03 7 | group 7  | 00:00:03 8 | group 8  | 00:00:03 9 | group 9  |
00:00:0310| group 10 | 00:00:03
 
(10 rows)
        regards, tom lane


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