Skip site navigation (1) Skip section navigation (2)

Re: Slow performance on Windows .NET and OleDb

From: "Greg Quinn" <greg(at)officium(dot)co(dot)za>
To: <pgsql-performance(at)postgresql(dot)org>
Subject: Re: Slow performance on Windows .NET and OleDb
Date: 2006-03-29 06:22:08
Message-ID: 006c01c652f9$1ca9c420$0200a8c0@pta.homex.co.za (view raw or flat)
Thread:
Lists: pgsql-performance
The query is,

select * from users

which returns 4 varchar fields, there is no where clause

Yes, I am running the default postgres config. Basically I have been a MySQL 
user and thought I would like to check out PostGreSql. So I did a quick 
performance test. The performance was so different that I thought PostGreSQL 
was nothing compared to MySQL, but now it seems its just a few configuration 
options. Strange how the defult config would be so slow...

I have begun reading the documentation but am not too sure what options I 
can quickly tweak to get good performance, could somebody give me some tips?

Thanks


----- Original Message ----- 
From: "Joshua D. Drake" <jd(at)commandprompt(dot)com>
To: "Jim C. Nasby" <jnasby(at)pervasive(dot)com>
Cc: "Greg Quinn" <greg(at)officium(dot)co(dot)za>; <pgsql-performance(at)postgresql(dot)org>
Sent: Tuesday, March 28, 2006 7:52 PM
Subject: Re: [PERFORM] Slow performance on Windows .NET and OleDb


> Jim C. Nasby wrote:
>> On Tue, Mar 28, 2006 at 02:14:00PM +0200, Greg Quinn wrote:
>>> Hello,
>>>
>>> I have just installed PostGreSql 8.1 on my Windows XP PC. I created a 
>>> simple table called users with 4 varchar fields.
>>>
>>> I am using the OleDb connection driver. In my .NET application, I 
>>> populate 3000 records into the table to test PostGreSql's speed. It 
>>> takes about 3-4 seconds.
>>>
>>> Even worse is displaying the 3000 records in a ListView control. It 
>>> takes about 7 seconds. In MySQL, the exact same table and application 
>>> displays the same 3000 records in under 1/2 second!!!
>>
>> Have you vacuumed recently? This smells like it might be a table bloat
>> problem.
>
>
> This could be a lot of things...
>
> He is probably running the default postgresql.conf which is going to 
> perform horribly.
>
> What is your work_mem? shared_buffers?
>
> Are you passing a where clause? If so is there an index on the field that 
> is subject to the clause?
>
> When you do the population, is it via inserts or copy?
>
> Joshua D. Drake
>
>
> -- 
>
>             === The PostgreSQL Company: Command Prompt, Inc. ===
>       Sales/Support: +1.503.667.4564 || 24x7/Emergency: +1.800.492.2240
>       Providing the most comprehensive  PostgreSQL solutions since 1997
>                      http://www.commandprompt.com/
>
> 



In response to

Responses

pgsql-performance by date

Next:From: Greg QuinnDate: 2006-03-29 06:24:58
Subject: Re: Slow performance on Windows .NET and OleDb
Previous:From: stefDate: 2006-03-29 06:08:15
Subject: Re: simple join uses indexes, very slow

Privacy Policy | About PostgreSQL
Copyright © 1996-2014 The PostgreSQL Global Development Group