There is a pgsql-performance list, which was created for questions like yours. 
Your problem was brought up many times before, so searching the archives is 
an alternative. 

Regards, Christoph 

> 
> Hi Everyone,
>  
> This is my first post here so please tell me to go somewhere else if this
> is the wrong place to post questions like this.
>  
> I am using PostgreSQL 7.3.2 and have used earlier versions (7.1.x onwards) 
> and with all of them I noticed same problem with INSERTs when there is a
> large data set. Just to so you guys can compare time it takes to insert
> one row into a table when there are only few rows present and when there
> are thousands:
> 
> Rows Present		Start Time		Finish Time
> ------------------------------------------------------------
> 100			1068790804.12       	1068790804.12
> 1000			1068790807.87	  	1068790807.87
> 5000			1068790839.26		1068790839.27
> 10000			1068790909.24  		1068790909.26
> 20000			1068791172.82		1068791172.85
> 30000			1068791664.06		1068791664.09 
> 40000			1068792369.94		1068792370.0
> 50000			1068793317.53		1068793317.6
> 60000			1068794369.38		1068794369.47
> 
> As you can see if takes awfully lots of time for me just to have those
> values inserted. Now to make a picture a bit clearer for you this table 
> has lots of information in there, about 25 columns. Also there are few
> indexes that I created so that the process of selecting values from there
> is faster which by the way works fine. Selecting anything takes under 5
> seconds.
> 
> Any help would be greatly appreciated even pointing me in the right
> direction where to ask this question. By the way I designed the database
> this way as my application that uses PGSQL a lot during the execution so
> there was a huge need for fast SELECTs. Our experiments are getting larger
> and larger every day so fast inserts would be good as well.
> 
> Just to note those times above are of INSERTs only. Nothing else done that
> would be included in those times. Machine was also free and that was the
> only process running all the time and the machine was Intel(R) Pentium(R)
> 4 CPU 2.40GHz.
> 
> Regards,
> Slavisa
> 

Fri, 14 Nov 2003 9:30:34 MET
Christoph Haller <ch@rodos.fzk.de>
Re: INSERT extremely slow with large data sets