From: "Lionel" <lionel@art-informatique.com>
Subject: Re: Which hardware ?
Date: Tue, 17 Jun 2008 19:59:45 +0200
Organization: Hub.Org Networking Services
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Message-ID: <g38u2m$2ua9$1@news.hub.org>
References: <g38epm$2pl4$1@news.hub.org>
	<20080617142501.GG68434@commandprompt.com>
	<Pine.GSO.4.64.0806171108060.7150@westnet.com>
	<dcc563d10806170842g6d039d7bsec81fb562ba9facd@mail.gmail.com>
	<Pine.GSO.4.64.0806171232390.10502@westnet.com>
	<dcc563d10806171007o719a2171o34e492f463a6c2f2@mail.gmail.com>
To: pgsql-performance@postgresql.org

"Scott Marlowe" wrote:
> You're absolutely right though, we really need to know the value of
> fast performance here.

the main problem is that my customers are used to have their reporting after 
few seconds.
They want do have 10 times more data but still have the same speed, which 
is, I think, quite impossible.

> If you're running aggregations of numbers used for filling out
> quarterly reports, not so much.

The application is used to analyse products sales behaviour, display charts, 
perform comparisons, study progression...
10-40 seconds seems to be a quite good performance.
More than 1 minute will be too slow (meaning they won't pay for that).

I did some test with a 20 millions lines database on a single disk dual core 
2GB win XP system (default postgresql config), most of the time is spent in 
I/O: 50-100 secs for statements that scan 6 millions of lines, which will 
happen. Almost no CPU activity.

So here is the next question: 4 disks RAID10 (did not find a french web host 
yet) or 5 disk RAID5 (found at 600euros/month) ?
I don't want to have any RAID issue...
I did not have any problem with my basic RAID1 since many years, and don't 
want that to change.